CATEGORY:
The Nature of Time Essay Contest (2008)
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TOPIC:
"Forget time" by Carlo Rovelli
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Carlo Rovelli wrote on Aug. 25, 2008 @ 18:36 GMT
Essay AbstractFollowing a line of research that I have developed for several years, I argue that the best strategy for understanding quantum gravity is to build a picture of the physical world where the notion of time plays no role at all. I summarize here this point of view, explaining why I think that in a fundamental description of nature we must "forget time", and how this can be done in the classical and in the quantum theory. The idea is to develop a formalism that treats dependent and independent variables on the same footing. In short, I propose to interpret mechanics as a theory of relations between variables, rather than the theory of the evolution of variables in time.
Author BioCarlo Rovelli is professor of Physics at the University of Marseille, France and member of the Institut Universitaire de France. His main research interests are in quantum gravity, where he has contributed to the definition and the development of Loop Quantum Gravity. He is particularly interested in the foundations of the physics of space and time. He has written the books: "Quantum Gravity" (2004), "What is Time? What is Space" (2004), and "Anaximander of Miletus" (2008). He has received the 1995 Xanthopoulos Award for his contributions to gravitational and spacetime physics.
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Anonymous wrote on Aug. 26, 2008 @ 10:37 GMT
I truly doubt that thermal time satisfies the properties that we usually expect from time. It might work for thermal equilibria, but what about states out of equilibrium? Especially those which are far out of equilibrium? If one place is hotter than another, does time run at different rates then? More disturbingly, let's say we have a plasma where the electron temperature is much much higher than the ion temperature. It will take quite some time before such a system will equilibriate, and so, it's possible to prepare such a system. Do the electrons experience a different clock rate from the ions then? At the same location? We know that the universe is clumpy; there are voids, superclusters, clusters, galaxies, stars, etc. So, the chemical potential varies from location to location (and so does the temperature). This means that the thermal time evolution has to be mixed with an approximately conserved baryon and lepton number symmetry which is "gauged" in the sense that it varies from point to point.
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Anonymous wrote on Aug. 26, 2008 @ 10:49 GMT
There's another huge problem with thermal time in a timeless universe with a thermodynamic arrow of time. If we choose to describe the ensemble at an earlier time, that would be different from describing the ensemble at a later time (based only upon the macroscopic degrees of freedom) because information is lost into microscopic correlations irreversibly. Which ensemble should we then use in a timeless universe? But if you say the earliest possible ensemble, then the flow of time would be way out of whack at "later times".
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Anonymous wrote on Aug. 27, 2008 @ 11:40 GMT
I think thermal time conflicts with the philosophy that time is what is measured by the correlation of partial observables with clock pointers. In a thermal equilibrium, clocks simply can't exist!
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Ming wrote on Aug. 29, 2008 @ 08:18 GMT
It seems to me that in terms of logical priority/primitivity, Quantum Theory (QT) should precede General Relativity (GR) as the more fundamental theory of Nature. Thus I believe we should take seriously what QT is telling us about Time and its peculiarities and try to derive GR as a macro approximation instead of doing it the other way round like the author is suggesting.
The Wheeler-DeWitt equation, upon which Rovelli's arguments (and very similar ones by e.g. J. Barbour) are based, is of questionable validity in reality due to the fact that we do not yet have any consistent theory of Quantum Gravity. Thus the "Timeless" world views inferred from it are of questionable validity as well, even if we don't consider the fact that these world views cannot be further from our physical intuitions...
Anonymous wrote on Aug. 29, 2008 @ 10:49 GMT
I take back my comments about the ambiguity in choosing the ensemble when there's a thermodynamic arrow of time. It shows that I still haven't gotten the central concept of timelessness, namely that the only instant which exists is "now", and that statements like the future or past state of a given state make no sense in a timeless universe. Timelessness is a theory of instants.
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C allen replied on Oct. 27, 2011 @ 13:41 GMT
How refreshing that rovelli proposes that there is no time. To understand this you have to imagine yourself in a universe with no matter - all is still and silent and dark. Then you see a planet and lo and behold suddenly there is movement -rotation etc. Only then when we measure it's evolution and it's becoming, only then do we employ ' time' as measurement. So there is only evolution and velocity.
Anonymous wrote on Sep. 1, 2008 @ 16:12 GMT
"At the same time, the entry should differ substantially from any previously published piece by the author."
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Alex Nelson wrote on Sep. 7, 2008 @ 04:16 GMT
"If one place is hotter than another, does time run at different rates then?"
Yeah it would logically since the energy at that point would be greater, so spacetime would be "more curved" (according to classical general relativity) which results in time "running faster"...so there's a sort of "limit" to what we already know right there! It'd be interesting to relate this to the relativistic red shift, and so on.
Actually, this quoted criticism is a sign of a good theory of time in itself in my opinion.
Alex Nelson wrote on Sep. 7, 2008 @ 04:50 GMT
Ming wrote: "The Wheeler-DeWitt equation, upon which Rovelli's arguments (and very similar ones by e.g. J. Barbour) are based, is of questionable validity in reality due to the fact that we do not yet have any consistent theory of Quantum Gravity."
Unless I am misinterpreting Dr Rovelli's paper, I think that he is calling the Hamiltonian constraint in general the "Wheeler-DeWitt equation" (as opposed to referring to the infamous one in the ADM forumalation of canonical general relativity).
In section V, where he discusses the "Wheeler DeWitt equation", it is merely some Hamiltonian constraint and nothing more. This is a constraint which always appears for relativistic systems, it seems to show up with relativistic particles and forces.
That's just my two cents though...
Dr. E wrote on Sep. 29, 2008 @ 21:08 GMT
Hello Carlo,
Thank you very much for the paper, which I enjoyed.
However, instead of forgetting time, perhaps we should forget quantum gravity for a moment? For while time manifests itself throughout classical, relativistic, and quantum mechanical physics and our empirical reality, the graviton has never been seen.
Do we have to quantize gravity? Could it be that nature is...
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Hello Carlo,
Thank you very much for the paper, which I enjoyed.
However, instead of forgetting time, perhaps we should forget quantum gravity for a moment? For while time manifests itself throughout classical, relativistic, and quantum mechanical physics and our empirical reality, the graviton has never been seen.
Do we have to quantize gravity? Could it be that nature is as it is, and that God or the Prime Mover/Creator came up with both QM and GR, which seem to coexist perfectly well in their current forms? For instance, this laptop computer is powered by quantum phenonema, and too, it is held on my lap by gravity. Each one has a role, and each seems perfectly content to play it. Perhaps both mathematical predictions and the experimental search for gravitons has fallen short because gravitons do not exist. Now this is no reason to stop looking, but too, it is not exactly a reason to keep looking, and it is certainly not a reason to get rid of time, which does seem to exist, as my laptop's clock tells me I am running late, yet again. :)
A book you would enjoy is Freeman Dyson's THE SCIENTIST AS REBEL. On page 219 Freeman Dyson writes,
"(Brian) Greene takes it for granted, and here the great majority of physicists agree with him, that the division of physics into seperate theories for large and small objects is unacceptable. General relativity is based on the idea that space-time is a flexible structure pulled and pushed by material objects. Quantum mechanics is based on the idea that space-time is a rigid framework within which observations are made. Greene believes there is an urgent need to find a theory of quantum gravity that works for large and small objects alike. . . As a conservative, I do not agree that a division of physics into separate theories for large and small is unacceptable. I am happy with the situation in which we have lived for the last eighty years . . . The question I am asking is if there is conceivable way we could detect the existence of individual gravitons. I propose as an hypothesis that it is impossible in principle to observe the existence of individual gravitons." --Freeman Dyson, THE SCIENTIST AS REBEL, pp 219-220
And yet, it is possible to observe, contemplate, experience, and witness time in multiple manners and ways.
I vote that we keep time. :) All I know is that we never have enough of it.
My simple theory--Moving Dimensions Theory--views time as a phenomenon that naturally emerges because the fourth dimension is expanding relative to the three spatial dimenions. Change is fundamentally woven into the fabric of spacetime via dx4/dt = ic, which makes sense, because change is fundamentally woven into our everyday existence, empirical observations, and all branches of physics! Indeed--it would not be possible to make a measurement without change! A great thing about MDT is that it allows us to keep all of relativity while unfreezing time and liberating us from the block universe, which is yet a meaningful artefact that arises from certain interpretations of relativity. And who knows, perhaps MDT will tell us something about quantum time, which will tell us something about quantum gravity. For MDT also provides a framework for quantum entanglemnt and nonlocality, and thus it provides a *physical* model underlying qm's inherent nonlocal, probabilistic nature.
Think about MDT as a simple *physical* unification of relativity and QM--both entanglement and nonlocality can be accounted for via the same principle that ensures a photon does not age, no matter how far it travels. A photon's timelessness, implied by relativity, represents a nonlocality in time. Both quantum entanglement and the agelessness of a photon descend from a common principle: dx4/dt = ic. A photon is matter that "surfs" the fourth expanding dimension, and thus it remains in one place in it, while traveling through the three spatial dimensions at c. Perhaps this is MDT's simplest proof: The only way to remain stationary in the fourth dimension is to move at c through the three spatial dimensions: egro, the fourth dimension is expanding relative to the three spatial dimensions.
And a great thing about MDT is that it also presents a *physical* model for entropy, as briefly elaborated on in my paper:
http://fqxi.org/community/forum/topic/238
MDT represents the kind of tehory we have not seen for awhile--a simple postulate and a simple equation that present a novel aspect of the universe--the fourth dimension is expanding relative to the three spatial dimension: dx4/dt=ic. This fundamental invariance underlies the invariance of the speed of light--both the constant velocity of c meausred by all inertial observers and, the constancy of c that is independent of the source. MDT also underlies relativity's two postulates, and all of relativity may be derived from its simple principle of a fourth expanding dimension.
In your conclusion your write, "It is possible to formulate classical mechanics in a way in which the time variable is treated on equal footings with the other physical variables, and not singled out as the special independent variable. I have argued that this is the natural formalism for describing general relativistic systems."
But when we look at Einstein's 1912 Manuscript, we see that time plays a different role from position. x1, x2, x3 represent the three spatial dimensions, which we generally use to demarcate position. And then along comes x4, which Einstein equates with ict. So as t progresses on our watches, x4 must progress. Time is very, very different from the three spatial dimensions! Perhaps it is not a dimension after all, but a parameter emerges because the fourth dimension is expanding relative to the three spatial dimensions, as suggested by x4=ict.
In your conclusion you also write, "The peculiar properties of the time variable are of thermodynamical origin, and can be captured by the thermal
time hypothesis."
But what underlies the "thermodynamical origin?"
MDT and dx4/dt=ic underlies time's thermodynamic arrow, and in my paper I account for and unify all of time's arrows and assymetries with MDT's simple postulate and equation. And in addition to this, all of relativity may be derived from MDT, while qm's entanglement and nonlocality are explained with a *physical* model, along with entropy.
Thanks for the paper Carlo!
As I write this, the DOW is down by 777! I have to run, so I apologize for any typos, as I only had time for one quick proofread. And once posted, these posts remain forever frozen in the past. :) There is no way to go back and change them--another proof that time travel into the past is impossible, which MDT agrees with.
Best,
Dr. E :)
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Quantum Gravity is a Multi-Million Dollar Hoax wrote on Oct. 11, 2008 @ 04:09 GMT
Do a search at NSF on "time quantum gravity."
http://nsf.gov/awardsearch/piSearch.do;jsessionid=7
F7E1A09E64B392775A7855BA8211E51?SearchType=piSearch&page=1&Q
ueryText=time+quantum+gravity&PIFirstName=&PILastName=&PIIns
titution=&PIState=&PIZip=&PICountry=&Search=Search#results
Yo
u will see that using quantum gravity to understand time is nothing new.
The research has received millions upon millions of dollars, and yet has produced abosolutely nothing but for aging quantum gravity regimes. NSF is just the tip of the iceberg.
All these millions upon millions, and yet, there is no:
1) graviton
2) consistent theory of quantum gravity, nor anything even close
3) any reason to go on
And yet, as the purpose of fqxi is generally to
1) fund well-funded, institutionalized crackpottery &
2) recreate physics in old physicists' image,
I imagine any essay that mentions time and quantum gravity will receive an award or two from the ruling pseudo-physicists.
Brian Beverly wrote on Oct. 11, 2008 @ 05:57 GMT
Quantum Gravity Conspiracy Theorist,
Your poorly copied URL link returns the following:
“Nothing found to display.”
I doubt this is your fault; instead these multi-millionaire physicists deleted all records to throw us off their trail. Congratulations you’ve earned a scooby-snack for all of your detective work. It is a shame that earlier generations fell for the “ether” hoax and wasted all that money on the Michelson-Morley experiment. Everyone should write their congressmen and tell them not to support null experiments before we spend any money on them.
Carlo Rovelli wrote on Oct. 13, 2008 @ 12:48 GMT
I try to reply to the various posts.
A certain number of posts raise a question that in my opinion is a very good and a very important question. The question, that some of the post present as a strong objection, is that the hypothesis of thermal time is not good, because it only deals with thermal equilibrium, while we need non-equilibrium states to have non-trivial time phenomena. I...
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I try to reply to the various posts.
A certain number of posts raise a question that in my opinion is a very good and a very important question. The question, that some of the post present as a strong objection, is that the hypothesis of thermal time is not good, because it only deals with thermal equilibrium, while we need non-equilibrium states to have non-trivial time phenomena. I think that this point is well taken, but also that I have an answer, which is the following. The thermal time hypothesis does NOT state that the only relevant quantities in the description of a system are thermodynamical. If it was so, I would agree that in an equilibrium state there would be no way of seeing time flow. Nothing happens to thermodynamical quantities, in equilibrium. However, all the usual dynamical variables exist and have their dynamics, even if immersed in a thermal state. To make this precise, consider for instance quantum field theory at a given temperature. This is a theory about a situation where there is a temperature, namely a state of equilibrium. But quantum field theory at a given temperature allows us to compute scattering amplitudes, propagation, et cetera, namely the same quantities as quantum field theory at zero temperature. Why? because it describe dynamical phenomena (say scattering) when there is an overall thermal bath "around" these phenomena. This is the context in which the thermal time hypothesis make sense. I am not saying that we only measure equilibrium thermal quantities. This would be manifestly in contradiction with everything we measure. I am saying that we measure dynamical phenomena (that, correlations between observables quantities) in a context in which there exists a thermal bath. (Concretely, this bath exists for real, given by the cosmic background radiation at 3K.) More technically, the thermal time hypothesis regards KMS states. Once a KMS state is given we can nevertheless measure quantities such as the correlations that are in fact in the very definition of the KMS states. These are explicitly time dependent. It is like observing "departures" from equilibrium, and study the way the behave.
A different version of the same question is formulated by the posts that ask whether bodies at different temperature define different times. I am not sure I have an answer to this point. But it important to recall that the thermal time hypothesis does not REPLACE dynamics. My entire point is that dynamics can be expressed as correlations between variables, and does not NEED a time to be specified. The thermal time is only the one needed to make sense of our sense of flowing time, it is not a time needed to compute how a simple physical system behaves. The last can be expressed in terms of correlations between a variable and a clock hand, without having to say which one is the time variable. Therefore the question about the flow of time defined by bodies at different temperature is a question about thermodynamics out of equilibrium. Unfortunately, like much of today's physics, I have not much to say on this. In any case, I am aware that the thermal time hypothesis is highly speculative. I would like the readers to keep it separate from the main idea defended in the essay, which is that mechanics can be formulated without having to say which variable is the time variable.
Another series of posts questions the validity of the Wheeler-DeWitt equation. I agree that at present we cannot rely firmly on a well defined version of this quantum gravity equation. But this is not what I mean when I talk about the hamiltonian constraint that define the dynamics. I refer much more simply, to the fact that ALL dynamical systems (classical) can be simply reformulated in a way that puts time on the same ground as the other variables, an din this case the dynamics is expressed by a "Wheeler-DeWitt-like" constraint. This idea is much older than me. I have only developed it and I have tried to use it as a general way to reformulate dynamics, without the need of singling out time.
One posts quote the phrase "At the same time, the entry should differ substantially from any previously published piece by the author." I suppose that this is a criticisms to the point that what I have written reflects things I have already published. I fully accept this criticism. In my understanding, the FQXi context is not the place for totally novel ideas. I suppose an scientist with a totally new idea would publish it on PRL, rather. The beautiful aspect of the FWXi context is that it opens a forum for focusing and expressing clearly the ideas that are around, articulating them and discussing them. I had never previously written a compact exposition of my ideas on time, which are either scattered in papers, or that require reading all my book, which technically heavy and the ideas on time are submerged by technicalities that have to do with quantum gravity and not just with time. In this sense, the essay for FQXi is, among my writing, strongly original. Of course parts of it do nothing but repeating points I have published elsewhere.
Dr.E. ha posted a friendly note, arguing that perhaps gravity needs not to be quantized, quoting Dyson on this, and pointing out his "Moving dimansion theory". I thank him for the indication. I'll look at it (I suppose this is one of the purposes of the Forum). I have also immense admiration for Freeman Dyson, but I think Freeman is wrong here. The need for quantum gravity does not come from the fact that we are disturbed by two different theories, and has little to do with seeing or not the graviton. It comes for our concrete interest in certain real phenomena, which we would like to study, and we have no theory for them. The main one is the early universe. If we take our gravitational theory seriously, as Freeman demands, we must conclude that the universe was in a state of over Planckian curvature sometimes in the past. On the one hand, we know for sure that generally relativity goes wrong in this regime. On the other, we have a simple explanation for this going wrong: quantum effects on the gravitational field are disregarded. Therefore the happy coexistence of general relativity and quantum mechanics, which was perhaps possible when Freeman was a younger man, and we knew less about the universe, is very, very hard to defend today. Either we find something else, or we are in the dark.
Then there is a post on the waste of public money on research about time in quantum gravity. I take this seriously. Often at conferences I listen to talk after talk, and I wonder "is public money wasted here"? Maybe yes. But was it wasted public money the money that the Ptolemy's Kings put in Ptolemy's astronomy? Or that the Church put in supporting Copernicus completely useless searches? Or that supported Maxwell and Faraday, Shcroedinger or Einstein? No, it clearly was not. Is there a way to chose a priori who will be next Dirac? No, there is not. Research needs courage, wasted time and money, false directions. The history of our civilization is the proof that all this money is not wasted, in my opinion.
Carlo Rovelli
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John Merryman wrote on Oct. 14, 2008 @ 02:20 GMT
Dr. Rovelli,
I would agree time is a measure of motion, similar to temperature, but that doesn't clarify how the effect emerges. Temperature is like a parallel processor, with lots of activity and interacting elements. Time is a serial processor, with the point of reference/observer/hand of the clock proceeding though a series of intervals/events. Observer and observed co-exist, as all elements in the thermal medium co-exist, so there is no dimensional projection out from this state. As a serial processor consists of innumerable serial processors, innumerable clocks exist in a thermal medium, as every point of reference moving in this thermal state constitutes the hand of its own clock, while all other points are face to that clock and hand of their own clock. So while all these points move from past events to future ones, the events, once created, are replaced by the next and so go from being future potential to past circumstance. Just as tomorrow becomes yesterday.
John Merryman wrote on Oct. 14, 2008 @ 02:24 GMT
Correction: fifth sentence; As a parallel processor consists of innumerable serial processors....
nnath wrote on Oct. 15, 2008 @ 00:42 GMT
This essay contest is wonderfully explaining how individuals have widely varying interpretations for a given phenomenon. This is parallel to a common man's observation when he listens to different eyewitnesses who happen to see the same event but their their descriptions vary substantially. Absolute truth appears a mysterious quantity and science can only describe relative truths about a process/phenomenon that change with time. There lies the mystery about time too.
Yoga is a technique to quieten the mind. It was evolved by a saint in India thousands of years back. That scripture has two relevant quotes about the search for truth. One states ' The cognizor, the process of cognition and the object of cognition must all merge in order to find the truth about the latter. Another states' there are mental distractions like ego or I-ness, ignorance, pleasure and pain which prevent the human thought processes from reaching the highest level required to get to the truth.Thus, without extreme humility and contemplation in 'silence', it is well-nigh impossible to know the 'truth'.
This comment is posted here but is too general to be applicable to all the contributors including the self!
Carlo Rovelli wrote on Oct. 15, 2008 @ 07:58 GMT
John Merryman's post says:
"I would agree time is a measure of motion, similar to temperature, but that doesn't clarify how the effect emerges." and then observes that temperature does not have the sequencial aspects that characterize time.
I thinnk that there is something vey interesting in this post, when it says "doesn't clarify how the effect emerges". My reply: "which effect?" What is the "effect" we are talking about here, and trying to understand?
The central point about all my ideas about time is to distinguish two different "effects". One is the observed fact that there are laws of nature that fix how variables are correlated. My claim is that this perfectly captured by our dynamical theory, but these theories do not truly distinguish "time varables" or "clock variables", from the other variables. This is effect one and point one.
But this is a bit unsatisfactory, because we have an idea of time as something "flowing", something very peculiar, very different from other variables. This peculiarity, this flowing, is effect two. So, the "effect" that remains to be understood is the peculiar impression we have about the flowing of time. The thermal time hypothesis states that this effect two is of thermodynamical origin. This is not my idea: it has long been remarked that all our impressions of "flowing" time are related to thermodynamics: only in a thermodynamical situation we may have irreversibility, for instance, and we may have memory. Eddintong has remarked that a periodic clock is not truly a clock unless we can count the cycles, namely unless we break periodicity. And we introduce some sort of irreversibility. Eddington noticed that the true prototype of a clock is not a pendulum: it is a burning candle (we ourselves are burning candles). A burning candle is a thermodynamical phenomenon. Going towards the future is mouving towards thermodynamical equilibrium.
So, summarizing: all temporal "effects" that are captured by ordinary mechanics have nothing to do with thermal time. They just have to do with the fact that there are laws that govern the relations among variables. The additional peculiar "flowing" of time is an "effect" which is not the same thing as temperature, but (if we believe the thermal time hypothesis) it emerges in a thermodynamca;/statistical situation only.
Carlo Rovelli
John Merryman wrote on Oct. 15, 2008 @ 16:10 GMT
Dr. Rovelli,
My point is that time and temperature are both descriptions of motion. Temperature is the level of activity against a given scale. Time is the rate of change relative to a given reference frame, or point. If you change the level of activity, you affect the rate of change. The candle burns faster if it is hotter. As a person in space ages slower than a person in a stronger and more active gravity field. So there is the element of time in temperature and the element of temperature in time.
Time has this sense of "flowing" because we exist as individual points of reference in a larger context, just as individual atoms of water move about in their fluid context, the whole of which is measured as temperature. Just as economic statistics function as a temperature reading of masses of human activity. So to the extent we "move" or "flow" within our medium, it moves the opposite direction. To the hands of the clock, the face moves counterclockwise. This manifests in the larger scale by the events which all these points of reference collectively create go from being in the future to being in the past, as each is replaced by the next, while those references go on to future events. Tomorrow becomes yesterday.
John Merryman wrote on Oct. 15, 2008 @ 16:33 GMT
Narendra Nath wrote on Oct. 16, 2008 @ 14:17 GMT
Dr. Rivoli,
Your idea to discard time as a variable appears fine. However, the concept of time appears hard to discard. It seems to me that the quantum conjugation of time with energy provides a possible way out of the problem of time. Initial distortions of time may have resulted in the release of the energy content of the Universe. Similarly, the space distortions provide the momentum, a combination of mass with motion. Without any motion or vibrations, the Universe will become meaningless. Pure, vibration free consciousness can not give rise to either mass or energy.
Conceptually, it may be possible to replace the time with some other physical quantity and still retain the physical explanations for various observed phenomena. you have proposed some kind of thermodynamical variable to replace time. However, i am unable to comprehend the basis and depth of your argument. I am an experimentalist among most of the essay authors who are theory experts! However, science is neither theory or pure experiment. It starts with some precepts based on observation and experience of the scientist. These are then translated into some viable logical concepts. After this gets done come the question of choosing the variables. The nature of variables again depends on what we take as dependent or independent entity. There can be a subjective element here. As Einstein often expressed that in spite of proposing the quanta of energy, he was unhappy with the quantum mechanical explanations of the phenomena that is entirely probabilistic in nature.
The nature can not be purely governed on such a consideration as it exhibits order, logic and symmetries, besides elements of random nature o/c impossibility of measurement on single event to study a process! Thus, the need for measurement requires averaging over several independent events. Order contains disorder but not vice- versa. Also, silence contains noise but not vice-versa. How to work out this dilemma, appears to be challenging in order to work out a single theory to explain everything!
Peter Morgan wrote on Oct. 16, 2008 @ 17:48 GMT
Dear Prof. Rovelli,
Your invocation of Tomita flow requires that the algebra of operators be, as you say, a von Neumann algebra, as well as requiring a state over the algebra. A von Neumann algebra has a Norm, by definition, which, I claim, must have a *timeless* meaning for your argument to go through.
The Norm of an algebra of observables decides what measurements are close to each other -- that is, the topology -- which allows us, by continuity, to decide whether we expect, in a given state, that the results of one measurement will be close to the results of another experiment. We can only verify that two given experimental procedures are close to each other by applying them to many different states, thereby determining that we get almost the same results (according to some Norm on the space of results) in every state. Given the statistical nature of a state -- as much in classical statistical mechanics as in quantum theory -- this requires us to construct many ensembles. Now, how are we to construct these multiple ensembles timelessly?
As an ideal world, of course, you are quite entitled to posit any mathematical structure you like, but I would like to see a Physical interpretation include at least a schematic for an operational correspondence with the world for every significant mathematical structure. In any case, given its significance to your account of time, I would like to see a relatively full account of how to understand the Norm of the von Neumann algebra in a timeless way, whether operational or not.
I apologize if this question is well understood. I don't follow the literature on quantum gravity closely at present. Please feel free just to cite a reference.
I'm perhaps simply at cross-purposes with you, since in the last sentence of section VI you assert that the world is "in" a given state rho, which suggests that you understand QFT in terms of a non-ensemble interpretation of probability. However, I would personally take a non-operational definition of probability also to be problematic for your program.
Eleni wrote on Oct. 17, 2008 @ 23:45 GMT
Thank you very much for the essay. I enjoyed reading it, I expect you will expand it more.
T.H. Ray wrote on Oct. 18, 2008 @ 12:34 GMT
Carlo Rovelli's statement, "Research needs courage, wasted time and money, false directions. The history of our civilization is the proof that all this money is not wasted, in my opinion..." is a point well made.
Nature shows in all ways that waste and redundancy are assets to creativity. Efficient evolution is guaranteed by conservation laws, and not by the efficiency that we vainly try to build into a system.
Tom
John Merryman wrote on Oct. 18, 2008 @ 17:32 GMT
Carlo Rovelli wrote on Oct. 19, 2008 @ 08:15 GMT
Thanks Eleni, Ray and John for the last nice posts.
Peter Morgan raises an extremely good issue, with both a technical and a conceptual side. I refer here to his post above, without trying to repeat here his points, since these are several, interconnected, and nicely expressed by Peter.
First, a technical point. It is true that Tomita theory wants a von Neumann algebra, and...
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Thanks Eleni, Ray and John for the last nice posts.
Peter Morgan raises an extremely good issue, with both a technical and a conceptual side. I refer here to his post above, without trying to repeat here his points, since these are several, interconnected, and nicely expressed by Peter.
First, a technical point. It is true that Tomita theory wants a von Neumann algebra, and therefore the corresponding norm; but this is given for free by the state over the C* algebra. The reason is that such a state is enough for the GNS construction, which provides the representation, the Hilbert space, and therefore the von Neumann algebra structure. Thus, C* algebra and (appropriate) state are enough.
This does not answer Peter's questions, however; it only moves them one step back, because all the physical questions he poses about the norm, and in particular the meaning of its its probabilistic interpretation in a timeless context, can just be reformulated for the state itself.
The question, I think, raises deep issues. I'll try to answer is steps. First, regarding the operational meaning of probability. I do not want to enter the debate about probability here. I only state my preferences, without arguments. The definition of probability that makes sense to me is the one of de Finetti, subjective. Probability is something about my expectations, and the corresponding mathematical theory expresses the proper way of adjusting expectations on the basis of observations, where "proper" refers to the use of Bayes theorem, which follows from the logic structure of probabilities (expectations) themselves. We make (finite) sequences of observations, and readjust our previous hypotheses on the basis of outcomes.
This answers the question about operationalism, but not the question about the possibility of doing so in a timeless context. This is the difficult part of the question. The question is about the rationalization of experiencial temporality in a physical world. I am not sure physics in the strict sense is capable of answering it. The question pertains to that part of science that studies ourselves and our capacity to gather and elaborate informationa and conceive thoughts and representations of the world. What I am saying is that I think that timeless quantum gravity is equally blind to the temporal aspect of consciousnes as Newtonian mechanics is. What basic physics must provide, however, is a context within which it is possible to have the basic ingredients in terms of which a science of complex systems might make sense of processes of organizing information. So, here is the story: In a timeless world, a small subsystem (us) whose interaction with the rest of the universe is limited to a very small number of variables, and therefore who has no access to the exact state of the rest of the universe (that is, it has the same state for many different states of the universe), can be correlated with the rest of the world in such a way to have an imprecise information about the rest of the system (a way to express these notions precisely using Shannon information theory is in my work on relational quantum theory); then with respect to this subsystem a Tomita flow is defined; and this flow itself is the physical underpinning of the perception of the flow of time, whatever this perception is.
Maybe I should not have entered this domain, which is slipery. I think that it is better to keep as separated as possible physics and the science about cognitive capacities. Otherwise we make confusion. As an analogy: we understand the water molecules, from there the hydrodynamica behavior of liquid water, from there the floating of boats, including the boat on which we stand when we collect water from the sea on order to study its molecular strucure. But trying to write a theory of molecular structure of water thinking that within the theory we may directly see out floating boat is the bad procedure. Here the analogy is: water molecules/timeless mechanics, floating/tomita flow, collecting water from the boat/operational definition of probability.
Hope this was not too confused.
Carlo Rovelli
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F. Le Rouge wrote on Oct. 19, 2008 @ 16:53 GMT
The way Dr Carlo Rovelli is questioning Time is may be new in 'Quanta Theory' but not in Antique Greek Metaphysics that does analyses the connection of Time with Space in Motion precisely. This is the case of 'Eleates' (6th bc - although Eleates deduce there is no motion at all!) and Eleates are not lonely.
No doubt that the analogy between the dynamism of Time and the dynamism of Heat is one of many comparisons that are leading to new 'kinesis'. One can find that in Boltzmann's science of gas pressure for instance. Therefore the 'Question of Heat' is as 'mysterious' as the 'Question of Time'.
Such a link between Heat and Time is established by some Antique Greek scientists too.
So the good question is not in my opinion if the Antique Greek Metaphysics is up to date or not; Dr C. Rovelli's essays are just proving it is still alive.
The right question is: do Greek old masters go beyond in time analysis than actual physicians? The goal is not to rise up old Methaphysics against modern Science but to know if the Greek Metaphysics can impulse a better logic to a technological Science that seem to be possessed by doubt in the field of logic.
(I am student in an Art-School and making an writing an essay about Geometry and Newton's chromometric scale. My interest goes to the problem of Time too. Even if I am not focused on number four and 'Quanta theory' which recalls the famous trial consisting in squaring the space of the circle, I intend to publish a chapter of my own iconoclastic artistic vision in a few days on www.fqxi.org).
John Merryman wrote on Oct. 19, 2008 @ 21:38 GMT
Dr. Rovelli,
I agree that the issue of consciousness distracts from the question of time. I think both time and temperature are elemental to motion. That said, our mental facilities are a consequence of feedback between the source of this consciousness and motion. E.O Wilson described the insect brain as a thermostat, while the neuroscientist J. B. Taylor provides interesting insights between the 'serial processor' of the left hemisphere of the brain and 'parallel processor' of the right hemisphere;
http://blog.ted.com/2008/03/jill_bolte_tayl.php#m
ore
I would argue that the right brained parallel processor amounts to a thermostat, in its measuring and reacting to the energies of the moment, while the left brained serial processor amounts to a clock, in that it analyses the sequential cause and effect of events.
John Merryman wrote on Oct. 19, 2008 @ 21:45 GMT
In traditional lore, this dichotomy was between the head and the 'heart.'
F. Le Rouge wrote on Oct. 19, 2008 @ 21:47 GMT
*Another analogy: keeping as separated as possible the physics and the science about cognitive capacities is probably as difficult as for the Greek scientists keeping physics and metaphysics separated.
Narendra Nath wrote on Oct. 20, 2008 @ 15:03 GMT
Does Dr. Rivolli think my posting unworthy of a response! i am however curious to know why he consider it to be so, just because it doesn't involve detailed discussion on the mathematical treatment used or the points raised are irrelevant!
Anonymous wrote on Oct. 20, 2008 @ 21:28 GMT
This is more like a paper than an essay. It also seems to be way over 5000 words.
report post as inappropriate
Carlo Rovelli wrote on Oct. 21, 2008 @ 16:47 GMT
Dear Narendra Nath, I am sorry, I did not think that your post unworthy of a response! I just did not know what to answer. Your suggestion that "distortions of time may have resulted in the release of the energy content of the Universe" is interesting, but I think is still to vague to be useful is physics. (By the way, my name is Rovelli, not Rivolli. But "Rivolli" sounds nice and funny to me... I might adopt it!)
Regarding the anonymous post "This is more like a paper than an essay. It also seems to be way over 5000 words.", I am also not sure what to say. Is this somebody interested in a scientific discussion or a contest competitor? :-) Anyway, the text alone without math gave less than 5000 words on my word counter. And I think the essay is an essay, not a "paper", whatever this means. It uses some technicalities, because I think they make the point concrete, but the main point is entirely a conceptual view about time, its absence, and its emergence.
Carlo Rovelli, (or Rivolli)
narendra nath wrote on Oct. 22, 2008 @ 10:24 GMT
Rovelli or Rivolli,
i enjoyed your pun, my mistake arose o/c the name of a cinema hall i use to visit in New Delhi to see western movies!
I have posted a latest one on the essay of Kyle Miller 'here and now'. That post is actually meant for we all the essays' authors. Kindly see it and then you and i will have no problem if you and i understand or not anything that any one else is saying or writing!!
F. Le Rouge wrote on Oct. 22, 2008 @ 11:07 GMT
Biology is crossing Physics in motion, either you take the Dynamics of Time or the temperature's one.
And both 'Quanta theory' - think of the motion of gas depending from temperature - and Relativity are based on reflexions on the arrow of Time AND the pillar of Temperature.
Light is the 'check point' of 'Quanta theory', Einstein's theories, without forgetting Newton. And the idea of Temperature and the idea of Time are included in ambiguous light.
This is the knot. And in my artist opinion, 'pulling the time over', Dr Rovelli is cutting the knot as Alexandre did (Although Aristotle was Alexandre's advisor and not Anaximander of Miletus).
Narendra Nath wrote on Oct. 22, 2008 @ 13:51 GMT
About your comment on energy coming from distortion in time, it is already covered under Heisenburg uncertainty relations, between two conjugate pairs E & T and X & P. Both energy and mass get created as uncertainty rise in time & momentum respectively. The former provides the classical way to explain overcoming of potential barrier the alpha particle experiences inside the unstable nuclei concerned.Near zero uncertainty in time means infinite energy uncertainty!Time may have begun this way!
Peter Lynds wrote on Oct. 22, 2008 @ 16:15 GMT
Dear Carlo,
I very much enjoyed your essay. Naturally, I very much agree with its general drive too. I have a question though. As a proponent (and founder) of Loop Quantum Gravity, are you not assuming the existence of time by asserting that time (and space) are quantized, and come as minimum, indivisible atoms in LQG? I think one can see this just in general, but also that by asserting the existence of indivisible, minimum time and space intervals, one is also assuming the existence of instants in time and spatial points (things that would constitute the building blocks of time and space and which certainly do not exist) to bound and determine such intervals. I naturally have no problem with Planck time and distance - intervals beyond which clocks and rulers can no longer have meaning – but this does not mean that continuity ceases beyond this point, not does Planck time and distance require the existence of instants and spatial points.
Best wishes
Peter
PS: I should note that, considering its emphasis on background independence and its adherence to 4-d, I find LQG the most promising current approach to quantum gravity. It is just the "atoms of time and space" that I have a real problem with. I'm not sure if LQG could be reformulated without this feature and still be "LQG" however.
Carlo Rovelli wrote on Oct. 24, 2008 @ 17:53 GMT
Dear Peter,
thanks for rising this key point. You say: "Are you not assuming the existence of time by asserting that time (and space) are quantized, and come as minimum, indivisible atoms in Loop Quantum Gravity"? Very good point. Here is what I think:
Einstein great discovery, of course, is that the two things are in fact the same. The two things are: on the one hand, the...
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Dear Peter,
thanks for rising this key point. You say: "Are you not assuming the existence of time by asserting that time (and space) are quantized, and come as minimum, indivisible atoms in Loop Quantum Gravity"? Very good point. Here is what I think:
Einstein great discovery, of course, is that the two things are in fact the same. The two things are: on the one hand, the gravitational field, and on the other the two "entities" that Newton put at the basis of his picture of the world, and called "space" and "time". Now, when you discover that mister A and mister B are the same person, you can equally say that mister A is in reality mister B, or that mister B is in reality mister A. Books like to say that the gravitational field, in reality, is nothing but the spacetime, which happens to curve and so on. I prefer the opposite language: namely that the entities that Newton called "space" and "time" are nothing else than the gravitational field, seen in the particular configuration where we can disregard its dynamical properties, and assume it to be flat. The choice is not just a choice of wording. My understanding is that the deep discovery of Einstein with general relativity is not that the gravitational field is very special, but, the other way around, that it is just a field on the same ground as the other fields. The key novelty with respect to pre-general-relativistic physics is that all these fields do not live "in" spacetime: they live, so to say, "on top of one another". (In fact, I think that this was also Einstein view. He writes for instance "Spacetime does not claim existence on its own but only as a structural quality of the [gravitational] field", in "Relativity: The Special and General Theory", page 155.) So, I think that the clearest way of thinking about general relativity, or, more precisely, the general relativistic theory that , at best as we know, describes our world, and which includes the gravitational field and all the other physical fields, is to view it as a theory of interacting fields, without any need of making reference to space and time. What we have is observable quantities that are functions of these fields.
Now, from this point of view (which is mine), the "atoms of space" of loop quantum gravity are truly just quanta of the gravitational field. The reason we call them "quanta of space" is only because we use to call "space" the quantity measured my a meter. But a meter only measures the gravitational field. And the same with time and a clock. The reason we keep talking about "space" and "time" in loop quantum gravity is only because these are traditional names for indicating aspects of the gravitational field. But these names are ill-used, if we assume them to carry all the heavy ontological significance of Newtonian space and Newtonian time. They represent observable variables (measured by clocks and meters), on the same ground as many other quantities observed in nature.
This is why I think that in order to have a clear picture the easiest thing is to "forget space" and "forget time", and only to talk about relations between observable quantities. The "atoms of space" and the "atoms of time" of LQG are only figures of language, to indicate that certain physical observables aspects of the gravitational field have a discrete spectrum.
I am very glad you have raised this point.
Carlo Rovelli
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Peter Lynds wrote on Oct. 24, 2008 @ 21:46 GMT
Dear Carlo,
Thanks. I thought that was an excellent response. I agree with everything you said as well. It's also nice as, with your interpretation of time and space in LQG, we both get to come away happy; no time, no space, no quantizaion of "time" or "space" etc. If only physics worked out this way all the time!
Best wishes
Peter
PS: I use that Einstein quote in my essay. It is remarkable how this point has been lost on so many.
John Merryman wrote on Oct. 25, 2008 @ 10:32 GMT
Dr. Rovelli,
One question with regards to space; Is this gravitational field ultimately a singular entity, as in Big Bang theory, or is it ultimately distributed, as in a fluctuating vacuum?
Given you describe it as "flat," I assume you think it is distributed.
Narendra Nath wrote on Oct. 26, 2008 @ 06:21 GMT
Drs. Rovelli, Merryman and other postings from public,
my comments here will concern the theme 'TIME'.Giving a meaning to life introduces time as a concept. It is at the root of life. Timelessness means that there is total freedom and complete randomness around. The latter is the scenario for all the physical processes/phenomena, as these have been understood only on probabilistic considerations. No individual event can be pre-detemined in time!
Now let us see what space is. If no location is desired, we have the spaceless situation. Only if one exists, it is enough for it to know it exists, no need for location. However, if two or more exist simultaneously, there is need for location in space. If we all agree to say that we are one then where is the need to assign different locations.
In psychology/logic, we deal with just 0 & 1 as the numbers. In fact, all other so-called digit numbers are obtainable through some manipulation of only these two digit numbers.The existence and non-existence can thus be treated as two sides of the same coin, both equally significant or insignificant. Such is the problem before us o/c the duality nature of all worldly things/matters.
An interesting combination of two set of terms and traits may be provide us with some humor! Let us take a set of service, love, knowledge and life. Then, let us take another set of attitude. reason, intellect and time. If we combine the corresponding terms and traits with words 'with' and then 'without' in turn, the net result comes out to be selfish,false,ego and finite in the first option. The other option provides us with selfless, true, ego-free and eternal. The latter is a desired ( theoretical) set of objectives while the former results in a factual( practical) situation.
Hope i have posted something down to earth with regard to TIME and its sister SPACE!!!
T H Ray wrote on Oct. 26, 2008 @ 09:29 GMT
I appreciate your careful distinction in previous works between partial observables (results of events in measure theory) and complete observables (number predicted by a mathematically complete theory).
Insofar as mathematically complete classical theories, such as special and general relativity, are time-dependent (even if time is only a theoretically useful fiction), it seems that indeed...
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I appreciate your careful distinction in previous works between partial observables (results of events in measure theory) and complete observables (number predicted by a mathematically complete theory).
Insofar as mathematically complete classical theories, such as special and general relativity, are time-dependent (even if time is only a theoretically useful fiction), it seems that indeed we can, and must, “forget time,” if the aim is a mathematically complete theory of quantum gravity; i.e., if QG predictions are manifestly not time dependent. After all, if a theory absent of time remains relativistic, space must be an illusion as well—as in Mach’s mechanics, the most relativistic of all theories, where space is also a useful fiction. A relativistic background-independent unification of classical statistical mechanics with quantum mechanics, then, demands complete background independence as the price for mathematical completeness.
So without time and space, it seems that only information states remain, as your thermal hypothesis holds. I acknowledge that a theory of thermodynamical/statistical interacting fields might be made mathematically complete, but can it be made plausibly physical? I mean by that, such a theory must predict nonlocal information states as the price of preserving the locality of partial observables, while complete observables remain out of reach.
You cite Smolin, “Challenges to the elimination of time…” and personally, my preference is toward Smolin’s emphasis on finite geometrical constraint on information flow (Bekenstein). He acknowledges in the end, “…if the universe is discrete and time is real, and is itself composed of discrete steps, then time may be none other than the process which constructs not only the universe, but the space of possible universes relevant for observations made by local observers.” If this is true, then partial observables cannot predict an event probability to a certain 1.0, and therefore cannot form the basis for a mathematically complete theory; time dependence, as in a classical theory, will stand in the way of complete observables. (Though I do not know enough to be sure of his motivation, I imagine that this may be one reason that Witten turned to TQFT—topological quantum field theory—where correlation of observables, rather than linear causality, obviates time dependence.)
However, Smolin turns over the other side of the coin in his very next statement, “Beyond this, there is the possibility of a quantum cosmology in which the actual history of the universe up till some moment and the space of possible universes present at that ‘instant’ are not two different things, but are just different ways of seeing the same structure, whose construction is the real story of the world.”
As we know, the technical word for Smolin’s observation is “duality”—there may exist theories of complete observables and theories of partial observables that are dual to each other. That is, where a mathematically complete prediction corresponds to the partial observable event probability 1.0. I think that, consistent with Smolin’s theme of “the present moment in quantum cosmology,” it is the principle of least action that preserves the present moment, as the least of all possible moments (discussed in “Time, change and self-organization;” Ray, ICCS 2007, NECSI).
Does not the least of all possible moments correspond to partial observables? Then, our experience of time is a subset of nature’s experience of time as described in a mathematically complete theory.
Thank you, Prof. Rovelli, for your always clear, straightforward and intellectually honest analysis.
Tom
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F. Le Rouge wrote on Oct. 26, 2008 @ 14:34 GMT
Let's forget the Time, then the Space, and why not the Matter after all? Let's move into a cadastral survey instead of real houses if the quantities and the variables are preceding the things and the matter and not deduced from them. That would be an original solution to housing crisis.
One can notice that, starting from the same mixing of Time and Space variables (which is not what Newton and Einstein are doing), Superstring theoricians are making n-levels buildings.
In my opinion, Rovelli's theory and Superstring's one are both 'interstitial' sciences. Translated in Aesthetics I would say they are 'musical'.
Dr. E (The Real McCoy) wrote on Oct. 27, 2008 @ 14:20 GMT
Hello Carlo,
Thanks for all the detailed responses above.
You write, "The "atoms of space" and the "atoms of time" of LQG are only figures of language, to indicate that certain physical observables aspects of the gravitational field have a discrete spectrum."
As gravity has never been quantized, and as gravitons have never been seen, and as neither time nor space has been quantized, and as "atoms of space" and "atoms of time" have never been seen in the lab nor universe, and as there is no consistent, finite, accepted theory that predicts atoms of space and time, I think it is erroneous to conclude that "certain physical observables aspects of the gravitational field have a discrete spectrum."
Perhaps I am misundertanding what you mean, but what are the "physically observable aspects" of the gravitional field which have a discrete, quantized spectrum?
Thanks Carlo!
Best,
Dr. E (The Real McCoy)
Peter Lynds wrote on Oct. 27, 2008 @ 17:40 GMT
Dear Dr. E,
I think he is referring to the "readings" of clocks and meters. Although these are observable, I should note that I disagree with Carlo that clocks and rulers measure anything. As they do not refer to anything except themselves, they themselves "represent" intervals of time and space. I think it is very reasonable to argue that the gravitational field is quantized, while the constitutes of clocks and rulers certainly are quantized. From this, one must operationally conclude that readings of cocks and rulers are quantized too. I think the crucial (and somewhat subtle) point, however, is that all one is essentially saying here is that matter is quantized - not that "intervals" of time and space are. Again, there is nothing "there" to be quantized. The problem obviously pops up when people then start talking about "time" and "space" actually being quantized, the existence of atoms of time and space, Chronons etc. This also means that, although Planck time and length represent an operational roadblock for clocks and rulers, there is no reason why continuity shouldn't be possible on possible smaller scales.
Best wishes
Peter
Dr. E (The Real McCoy) wrote on Oct. 27, 2008 @ 19:38 GMT
Hello Peter--'tis an honor to hear from you! I have been a fan ever since I read your paper on Zeno's paradox a few years back on slashdot. I reference your work in a longer treatment of Moving Dimensions Theory.
Yes--you write, and I agree, that "Although these are observable, I should note that I disagree with Carlo that clocks and rulers measure anything. As they do not refer to anything except themselves, they themselves "represent" intervals of time and space."
I think you will greatly enjoy the attached informal treatment of clocks and rulers given by Moving Dimensions Theory, which accounts for the gravitational redshift and the gravitational slowing of clocks, while also showing that there is no need to quantize gravity. Space is seen as continuous, and quantum phenomena (wave-particle duality/nonlocality/probability) is seen to descend from the fundamental wavelength of the fourth dimension's expansion, from which relativity is derived in my paper. dx4/dt = ic, and the wavelength of this expansion is Planck's length. And every timeless, ageless photon, which remains stationary in the fourth expanding dimension, agrees! It also deals with Planck's length in a novel, sensical manner.
The tautological definitions of time and the velocity of light, rest upon MDT’s fundamental invariant of dx4/dt=ic, which ensures that c is always measured to be c, even though the rate of time changes close to gravitational masses. MDT’s invariance underlies Einstein’s observation, “My solution was really for the very concept of time, that is, that time is not absolutely defined but there is an inseparable connection between time and the signal [light] velocity.”
Thanks for the words! Enjoy the attached brief paper--an updated version of what I posted on my own topic earlier today.
attachments:
MOVING_DIMENSIONS_THEORY_EXAMINES_THE_GRAVITATIONAL_REDSHIFT_MCGUCKEN.pdf
Narendra Nath wrote on Oct. 28, 2008 @ 02:23 GMT
Dear Carlo, you have the distinction of having the highest postings thus far. It is fine as the essay is invoking wide response. However, may be, don't we all need to broaden our overall outlook on the subject, rather than sing our individual 'songs'. The truth is never confined to an individual. It encompasses us all and unites us with the creation itself! i still await your specific comments on the posting made on Oct 26. it appears naive in nature but we need to contemplate deeper, beyond our individual scientific achievements may be!
In a strange layman's way, i hint at dispensing with both space & time but not 'gravity' as a concept! i also seem to have reservations about Quantum Mechanics, in a small way similar to what Einstein himself opined at its possibly better alternative to emerge one day!!
Clinton "Kyle" Miller wrote on Oct. 28, 2008 @ 21:01 GMT
Dear all,
I wanted to make some comments about this "essay" along with the comments I have seen above.
I wanted to point out the comment made by Narendra (which has seeminly gone unnoticed):
"An interesting combination of two set of terms and traits may be provide us with some humor! Let us take a set of service, love, knowledge and life. Then, let us take another set of...
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Dear all,
I wanted to make some comments about this "essay" along with the comments I have seen above.
I wanted to point out the comment made by Narendra (which has seeminly gone unnoticed):
"An interesting combination of two set of terms and traits may be provide us with some humor! Let us take a set of service, love, knowledge and life. Then, let us take another set of attitude. reason, intellect and time. If we combine the corresponding terms and traits with words 'with' and then 'without' in turn, the net result comes out to be selfish,false,ego and finite in the first option. The other option provides us with selfless, true, ego-free and eternal. The latter is a desired ( theoretical) set of objectives while the former results in a factual( practical) situation."
This makes a very important distinction between the products of science (Narendra's practical situation) and the aspirations of humanity (Narendra's theoretical set).
I wanted to comment that while this is indeed an "essay contest" that, in reality, there is no conclusion. There is no ultimate truth which science can obtain, there will always remain the largest questions: why something rather than nothing?
However, I want to make it clear that science is my greatest passion. Yet I see science today as an faint glimmer of what it could be. We lack the heroic attitude as Dr. E has made quite evident in his postings and essay. We also have 'sold' nature short--instead of letting children witness the awe and wonder of the cosmos, we placate them with ideas such as the "big bang" which remain hypothetical. Rather than telling children our biggest problems we tell them our greatest accomplishments, we hail the paradigm of evolution; yet, the origin of life will remain an eternal mystery. I do not want to go on forever like this but I think the reader might begin to see what I am saying, as I have experienced it my whole life (for the interested reader please see John Horgan's "The End of Science").
I think we scientists need to be careful when talking about "the truth". We must realize that science is the attempt to answer the question—Who are we?—through the conceptualization of this question via the emergent phenomenon of “working-memory.” This emergent property of the human brain is coupled to our conscious awareness, that is, the here-and-now. Thus, science is a form of consciousness: since consciousness is the conceptualization of the here-and-now through “working-memory.” Therefore, science is a metaphor, a lie—just as all forms of art are a lie—but, it is a lie that reveals the truth: reality is what we experience in the here-and-now, and life is what one makes of it.
And so, science and the humanities stand as complementary entities—exploring and expressing our objective physicality and subjective mentality, respectively. This is why neither can lay claim to "the truth" rather they both show us that the answer is not *out there* or *in here* but is really found in realizing our shared mortality.
The belief in a ‘material universe’ is no more realistic than an almighty ‘God.’ Both of these forms of faith can foster a form of fundamentalism: be it ‘scientism’ or ‘religious radicalism.’
“The characteristic of all fundamentalism is that it has found absolute certainty—the certainty of class warfare, the certainty of science, or the literal certainty of the Bible—a certainty of the person who has finally found a solid rock to stand upon which, unlike other rocks, is “solid all the way down.” Fundamentalism, however, is a terminal form of human consciousness in which development is stopped, eliminating the uncertainty and risk that real growth entails.” - Heinz R. Pagels
In the realm of ideas, there stands two polar opposites: solipsism and materialism. Both of these ideologies represent subjective doctrines of consciousness; they are unfalsifiable. However, death stands as the single solace of reality in our world. Beyond our relationships with the mind and body, we have our relationship with others. And we all know we are going to die someday.
Even so, I still cannot be sure that this world is not some type of solipsistic nightmare; or I might be "plugged into the matrix"; and it also might be the case that my conscious awareness is nothing but the random collisions of atoms. But I do find comfort in my certainty of ordinary death. Without this certainty my life would no doubt fade into meaninglessness.
Humanity has struggled since the dawn of history to expound itself, and ironically it now seems that the highest form of consciousness is derived not from some platonic postulate, abstract mystical enlightenment, or any other haughty ideology. But from a solid relationship with mortality—the one actuality that binds us all to the same fate—the fundamental essence to realizing the miraculousness of existence.
CKM
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John Merryman wrote on Oct. 29, 2008 @ 02:30 GMT
Kyle,
The knowledge of our being recedes into the past, but it propels the essence of our being into the future.
Without knowledge there is no past. With no past, there is no future.
Narendra Nath wrote on Oct. 29, 2008 @ 02:58 GMT
Dear Kyle and Carlo,
Our essay discussions are joining the voices of young 20 yrs with elders over 75 yrs. The wide spectrum provides the wealth hidden in our deliberations. We all need to assimilate the differing points of view and then comprehend them as mere complementary to one another. Thus, humanity gets enlightened.
If we try to work a bit harder and concise our presentations in discussions, the impact will be greater. Details are mere words that are used to expand the basic points of view!
i still await the response of our learned author, Carlo to the postings made on 26 and 28 Oct. by me!
As 'consciousness' is being used and invoked quite often in our discussions, i will attempt to add a few points:-
1. Actions take place through consciousness while our thoughts are with or without the same.
2. Energy for It comes from knowledge
Narendra nath wrote on Oct. 29, 2008 @ 03:21 GMT
unfortunately, my posting got on the site, without my completion, sorry for interruption!!
2. Energy comes from knowledge and enhancement comes from the 'wisdom' component.
3. Motivations lie in self will and desires. However, one needs to be careful to maintain smooth coordination between wisdom, will & desires, as these traits build ego too. It is
good to temper acts with a spirit of continuity, giving and observing the apparent opposites with calmness and reconciliation.
4.Waking, dreaming and sleep are the three known states, to which 'meditation' may be added. It is a state where we know 'we exist' but we become unaware of 'where we are'.This help provides freshness, sensitivity and all-encompassing beauty to the train of thoughts within. One is awake restfully!
5.Each body cell has life-force independently. Normally, a person has many cells in decay mode or even dead. Meditation helps individual cells to get strengthen and provide 'bubbly' enthusiasm in our actions.
6. Power of observation, differentiating discrimination and clarity gets enhanced.
Dr. E (The Real McCoy) wrote on Oct. 29, 2008 @ 20:15 GMT
Thanks for the rockin' words Kyle!
You write, "However, I want to make it clear that science is my greatest passion. Yet I see science today as an faint glimmer of what it could be. We lack the heroic attitude as Dr. E has made quite evident in his postings and essay. We also have 'sold' nature short--instead of letting children witness the awe and wonder of the cosmos, we placate them with...
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Thanks for the rockin' words Kyle!
You write, "However, I want to make it clear that science is my greatest passion. Yet I see science today as an faint glimmer of what it could be. We lack the heroic attitude as Dr. E has made quite evident in his postings and essay. We also have 'sold' nature short--instead of letting children witness the awe and wonder of the cosmos, we placate them with ideas such as the "big bang" which remain hypothetical. Rather than telling children our biggest problems we tell them our greatest accomplishments, we hail the paradigm of evolution; yet, the origin of life will remain an eternal mystery."
A great thing about this discussion are the young voices who don't have a dog in the fight in the string/lqg/quantum gravity wars, and who see that physics is ultimately not about winning prizes in "The Matrix"--some socially-contructed arena built with PR and hype, but physics is about that long, rugged journey that we find ourselves on while seeking to aprehend *physical* reality.
Thanks to fqxi.org for this wonderful forum and the ocncept of the essay contest! Surely this is a format superior to arxiv.org, which hasn't exactly lead to any advancements in physics. . .
Max Born wrote, "All great discoveries in experimental physics have been made due to the intuition of men who made free use of models which for them were not products of the imagination but representations of real things."
And yet, today, the quantum gravity regimes have rejected simple physical models along with the belief that the math ought represent *real* things. And thus, despite hundreds of million in funding, there is no quantum gravity. There is no graviton, nor any consistent theory of quantum gravity. Instead, there are literally an infinite number of string theories, and fair about of loop-quantum theories, none of which quantize gravity in any finite, consistent way; let alone in any way that makes predictions that can be tested. There is no proof whatsover for tiny, vibrating strings, nor atoms of space and time, nor twistors, nor tiny little loops, nor multiverses, nor hyperspace, nor parallel universes. And the Greats themselves--Nobel Laureates--both living and dead, have spoke out against such pseudo-science, which has become a religion.
Instaid we get communal efforts which end up opposing progress in physics, as they oppose the individual heroic spirit by which all higher physical truths are ultimately apprehended.
Science is more of an art than a science, and it always seems to advance in manners never before anticipated by the establishment, as Planck stated. One cannot legislate, nor vote on, nor dictate the advancement of science by fiat. Do not take my word for it.
"One cannot pray a lie," as Mark Twain once said.
"New scientific ideas never spring from a communal body, however organized, but rather from the head of an individually inspired researcher who struggles with his problems in lonely thought and unites all his thought on one single point which is his whole world for the moment." --Max Planck
And again we see the primacy of the honest individual in the classic, epic hero's journey!
"A hero ventures forth from the world of common day into a region of supernatural wonder: fabulous forces are there encountered and a decisive victory is won: the hero comes back from this mysterious adventure with the power to bestow boons on his fellow man." --Joseph Campbell
http://en.wikipedia.org/wiki/Monomyth
And the Nobel Laureate eocnomist F.A. Hayek agrees!
"The tragedy of collectivist thought is that, while it starts out to make reason supreme, it ends by destroying reason because it misconceives the process on which the growth of reason depends. It may indeed be said that it is the paradox of all collectivist doctrine and its demands for “conscious” control or “conscious” planning that they necessarily lead to the demand that the mind of some individual should rule supreme—while only the individualist approach to social phenomena makes us recognize the superindividual forces which guide the growth of reason. Individualism is thus an attitude of humility before this social process and of tolerance to other opinions and is the exact opposite of that intellectual hubris which is at the root of the demand for comprehensive direction of social purpose." –F.A. Hayek, The End of Truth, The Road to Serfdom
Along comes a scientist who agrees with Einstein and Max Born and Planck. Along comes a physicist who agrees with Wheeler, and Feynman, and Glasgow, and Godel, and Bohr, and Gamow--wishing that he could watch old Westerns with Bohr and Gamow. Along comes a scientist who agrees with Nobel Laureate Robert Laughlin and Nobel Laureate F.A. Hayek, with Newton and Dirac, with Heisenberg and Minkowski, with the great mythologist Joseph Campbell. Along comes a scientist with simple theory that has a simple postulate and equation from which all of relativity may be derived; from which entropy naturally arises, and which accounts for time and all its arrows and assymetries across all realms, while also providing a *physical* model for entanglement and nonlocality, as well as a *physical* model for Huygens' principle and the Heisenberg Uncertainty principle. Not only does the multi-billion-dollar physics establishment ignore it, but they have so much funding, that they can hire grad students and profesors to snark the theory, so as to defend their perptual-motion NSF money mahcines and religions of wormholes, time warps, quantum gravity, multiverses, tiny, vibrating strings, and geometric mysticism/PR/hype, which Moving Dimensions Theory has no need for, as it concerns itself with physics and physical reality--with logic, reason, and simple postulates and equations that represent a hitherto unsung universal invariant--the fourth dimension is expanding relative to the three spatial dimensions at c.
What we have here is a modern-day Inquistion.
Check out:
http://www.jklarsen.com/myblog/index.php?blog=6&title=co
nfession_of_galileo_galilei&more=1&c=1&tb=1&pb=1
Where it is reported: "In 1633, physicist Galileo Galilei was brought before the Roman Inquisition. Tried on "vehement suspicion of heresy," Galileo was forced to swear that he "abjured, cursed and detested" the errors of his work, which extended the findings of the Polish astronomer Nicholaus Copernicus that the Earth Moves."
Now I have postulated that the fourth dimension expands relative to the three spatial dimensions, and not one person in the entire quantum gravity regime has ever, ever, taken the time to comment on my theory. It's not like MDT is a secret, so their silence puzzles the will. Carlo promised to look at my paper above, but he has not yet commented on it.
I realized that perhaps before commenting on MDT, they are all waiting for a confession.
Well, here is my confession, based on Galileo's, which can be enjoyed here:
http://www.jklarsen.com/myblog/index.php?blog=6&title=c
onfession_of_galileo_galilei&more=1&c=1&tb=1&pb=1
I, Dr. E, son of the late Vincenzio Galilei of Florence, aged 70 years, tried personally by this court, and kneeling before You, the most Eminent Antitheorists and Reverend Lord Cardinals of M-Theory Multiverses, Inquisitors-General throughout the Quantum Gravity Republic against heretical depravity, having before my eyes the Most Holy Gospels of an Elegant Universe, Not Even Wrong, and The Trouble With Physics, and laying on them my own hands; I swear that I have always believed, I believe now, and with Ed Witten's help I will in future believe all which the Holy Quantum Gravity and M-Theory Church doth hold, preach, teach, and hype to the press, including E-8 and next year's E-9 anti-theory.
But since I, after having been admonished by this Holy Office entirely to abandon the false opinion that the fourth dimension expands relative to the three spatial dimensions, and that quantum mechanics' entanglement, nonlocality, entropy, relativity itself, time and all its arrows and assymetries across all realms, the gravitational slowing of clocks and time, Huygens' Principle, probability, and all the dualities (space-time, wave-particle, mass-energy) derive from this simple principle of MDT and its equation dx4/dt=ic, and that I was neither to hold, defend, nor teach in any manner whatever, either orally or in writing, the said false doctrine; and after having received a notification that the said doctrine is contrary to the Holy Writ of Hyperspace, I did write and cause to be printed a blog and forum in which I treat of the said already condemned MDT doctrine, and bring forward arguments of much efficacy in its favour, without arriving at any solution: I have been judged vehemently suspected of heresy, that is, of having held and believed that the fourth dimension's expansion is the universe's fundamental invaraint, and that the block universe does not exist and time is not the fourth dimension, but that time is a parameter that emerges because the fourth dimension is expanding relative to the three spatial dimensions at c, that change is and ought be woven into the fundamental fabric of spacetime with dx4/dt=ic, and that the fourth dimension, like the earth, does move.
Nevertheless, wishing to remove from the minds of your Tenured Eminences and all faithful LQGers and String Theorist this vehement suspicion reasonably conceived against me, I abjure with sincere heart and unfeigned faith, I curse and detest the said errors and heresies, and generally all and every error and sect contrary to the Holy Quantum Gravity Regimes, and I am ready to foregt time, forget space, and forget physical reality, while embracing multiverses and tiny, vibrating stirngs. And I swear that for the future I will neither say nor assert in speaking or writing such things as may bring upon me similar suspicion; and if I know any heretic who speaks out against tiny, vibrating branes, anti-theories, or atoms of space and time, or one suspected of heresy, I will denounce him to this Holy Office of Time Travel, or to the Inquisitor of Wormholes and Ordinary of the place in which I may be, which will of course be in the block universe, which MDT falsely liberated us from, while falsely grangting us free will and free thought, as it falsely froze time. I hereby remit all future free will, as I return to the block universe with the hopes of receiving the funding that is a part of my pre-Ordained future, as a member of the Quantum Grvaity Church.
I also swear and promise to adopt and observe entirely all the penances which have been or may be by this Holy Office of Loops imposed on me. And if I contravene any of these said promises, protests, or oaths, (which Ed Witten forbid!) I submit myself to all the pains and penalties which by the Sacred Canons of String Theory and other Decrees of D-branes general and particular are against such offenders imposed and promulgated. So help me God and the Holy Warped Passages/The Trouble With Physics/10^99 indecipherable arxiv.org papers--which I touch with my own hands.
I, Dr. E, aforesaid have abjured, sworn, and promised, and hold myself bound as above; and in token of the truth, with my own hand have subscribed the present schedule of my abjuration, and have recited it word by word. In America, at the Convent della Minerva, this 28th day of October, 2008, right before I go shopping for my Halloween costume.
I, Dr. E, have abjured as above, with my own hand."
And as I'm walking away to serve out my house arrest after this confession, I turn to the crowd that had gathered to hear me read it and smile.
And I say, "And yet it--the fourth dimension--moves! Eppur si muove!"
http://en.wikipedia.org/wiki/E_pur_si_muove
Happy Halloween everyone!
I think I'm going to celebrate our newfound free will and liberation from the block universe, frozen time, and frozen progress in physics by being a cowboy this year, in honor of Galileo, Bohr, Homer, Gamow and all those classical heroes--so many of them unsung.
Thanks to fqxi.org for this wonderful forum and to all the participants!
Best,
Dr. E :)
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Narendra nath wrote on Oct. 30, 2008 @ 05:23 GMT
Real McCoy (Dr.E), Kyle & Carlo Rovelli, the author,
i am getting confused with author's wise silence while Dr. E continues with his lengthy comments. The young Kyle put in some freshness as expected from the young but most of us continue to sing about ourselves. May we all join to bring cohesion, preciseness to our large number of postings on this essay. i firmly believe science can only talk about relative truths and none of us need bother philosophically to project the ultimate truth. Theories have names tied just as each of us have a tie with a name. Neither seem to hold for long. Only when one has the capacity to broaden to the level of cosmos and then comprehend the phenomenon being attempted for explanation,the right direction is likely to be missed!
IT IS TIME CARLO COMES UP WITH RESPONDING POST and clear the mess from building up!
Paul N. Butler wrote on Oct. 30, 2008 @ 08:37 GMT
Carlo and all previous responders;
I find it amazing how one can dance completely around a point without seeing it, but we are all somewhat subject to that problem so I can’t say too much. First many picked up that time seems to be connected to motion, which is true. It is also interesting that you desire to replace time with thermodynamics, which can generally be considered to be a...
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Carlo and all previous responders;
I find it amazing how one can dance completely around a point without seeing it, but we are all somewhat subject to that problem so I can’t say too much. First many picked up that time seems to be connected to motion, which is true. It is also interesting that you desire to replace time with thermodynamics, which can generally be considered to be a study of the generalized quantitive motion of a large number of particles traveling through distances as a contained or isolated group (of course, the relative equilibrium of the motions etc. is also a part of it). This is because you are substituting time in one form with time in another form.
Time is a derived function of two variables. They are distance and motion amplitude, where time equals distance divided by motion amplitude (usually called rate or speed) or T=D/R. Distance is the more fundamental variable since it is a property of and emerges in any dimensional system that contains at least two identifiable points as the separation between the two points. Motion is a property of an entity that exists within such a dimensional system. Distance exists as a part (property) of the dimensional system, but an entity must exist in the system to carry motion through the distance. The simplest concept of an entity is one that is composed of motion. The motion contains within itself such information as its position, direction, and amplitude as it travels through the distance between the two points. From this it is possible to generate the complete physical world as a large motion machine in which each particle of sub-energy, energy, and matter is composed of a motion in each of the dimensions in which it participates.
There is no flowing of time as a separate thing from the motions that exist in the entities that exist in the dimensional system. The perception of time flowing is caused by the fact that we exist in a continuum of motion composed of a vary large number of individual motions that are moving in relation to us and are also actually even going on in our own bodies. As an example, if you call a taxi and then wait by the street for it to come so you can get into it, when you see it coming down the street a few blocks away, the action of getting into the taxi is still in the future. When the taxi reaches you and stops and you begin to reach out your hand to open the door, the action of getting into the taxi is now in your present. After you have opened the door entered the taxi, told the driver your destination, and closed the door, the action of getting into the taxi is complete and becomes a part of your past. What has happened, however, is a continuum of motions. You’re feeling of the flow of time from the future to the present and then to the past is just a matter of the relationships between motions in terms of your planned (in this case) action of getting into the taxi. It has to do with the relative positioning of the motions in relation to each other. This type of serial sequence of motions is one thing that gives us a sense of the flow of time. Another is the fact that the world is alive with motions all around us. This continual bombardment of motions on our senses that changes in many ways as we and they move, gives us a sense of placement in and movement in time by the markers of the motion content that are continually changing. Repetitive motions also add to the sense of the flow of time as measured by the number of repetitions. Time then is not a separate entity that somehow flows in one direction, but the measurement of motions through distances. It is the motions themselves that give us the sense of flow as they flow all around us. When you understand that it is the continuum of motions that are flowing, it is easy to see why they only go in one direction because a motion goes in one direction until it is acted upon by another motion and then it may go in a different direction or at a different motion amplitude as a result of the interaction. This pattern of motions and interactions between motions is continually happening all around us. The only way to go back in time (or at least appear to do so) would be to simultaneously reverse all motions in the universe and then reverse them again when they were back to the positions that they were in at the previous condition of all motions that you wanted to get back to. You could then relive the same pattern of motions over again, but you would not know it because you would have also reversed your own motions and all of the motions that stored your remembrances of the previous motion passage would be reversed also and would thus remove your memory of that first pass though of the motions. There is no past to travel to because all of the interactions that have brought motion conditions to the place that they are now at have effectively erased those past motion conditions and the motion conditions that will be in place in the future are not there yet because all the interactions that will take place from now to the place you want to go to in the future have not yet occurred and so the future motion conditions don’t yet exist either.
Now the easy way to get around using time in your equations is to replace time (T) with the variables that make it up (D/R). The only problem is to replace (R) with a motion amplitude function that does not contain time, but instead is generated as a position on a continuous motion amplitude scale of the range of possible comparative motion amplitudes. This would have a certain chosen motion amplitude as the unit of motion amplitude and all compared motions would then be expressed in terms of that unit. If the proper unit is chosen you might be surprised at how it might make some other things easier to understand hint, hint. Of course you must remember that distance also becomes a multi-amplitude function in matter at high velocities and you must properly account for it.
Time standards are actually just specific sets of distances and their associated motion amplitudes that generate the same result when you divide the distance by the motion amplitude. As an example, one standard is the day, which is the time that it takes the earth to make one rotation on its axis. If you look at a line of points that go from the equator to one of the poles, you see that as you travel from the equator toward the pole each point has a slightly shorter distance to travel than the point before it to get all the way around the earth. In order to get around the earth when all the other points on the line do, it must, therefore, travel with a slightly lower motion amplitude than the point before it and a slightly faster motion amplitude than the point after it. This continues for all the points on the line so you get a continuous spectrum of distances and their associated motion amplitudes that equal one standard day. Of course, any other motion that went through a specific distance with a specific motion amplitude that would be completed in one revolution of all those points on the earth around the center of the earth would also be part of the standard set of one day.
Once you can get centered on the concept that motion is the key to the generation of all entities (energy photons, matter particles, etc.) the next step is to consider how many motions are required to make them all up, what dimensions the motions travel in and what type of dimensional interfaces are necessary to make it all work. Just to cover some very basic concepts, we know from E= MC^2 that energy and matter are basically the same thing, but it takes a large amount of energy to make a small amount of matter. If all entities are composed of motion, it follows that matter contains more motion than energy. We know that motion on a large scale generates mass effect in that a truck that is traveling at 40 mph will usually display about twice the mass effect as it would if it was going 20mph on an object that it hits. This can be extrapolated to all entities with the concept that motion equals mass. So in general matter particles possess a greater motion content and, therefore, also display a greater mass effect than energy photons. If you try to slow an energy photon down to stop its motion, its mass effect decreases and it eventually ceases to exist, but you can bring a matter particle to a complete stop in the first three dimensions and it still retains its mass effect. This implies that the motion is stored differently in the two types of entities and that the motion in the matter particle is somehow bound up in the particle itself and is separate from its three dimensional motion. The motion stored in the energy photon that is depleted as you try to slow it down is also not its three dimensional motion as it continues to move at the speed of light. It, therefore, also contains an additional motion that is stored in some other way than in the lower three dimensions. The energy photon also displays a frequency and wavelength effect with a variable mass effect such that if you try to slow it down its frequency and variable mass effect decrease and its wavelength increases. This can give us a good hint at what type of dimensional interface would be necessary between the dimension that stores its extra motion and the first three dimensions in order to generate these effects. The matter particle also demonstrates a frequency and wavelength effect so it also likely stores some of its motion in the same way as the photon, but in addition it stores some of its motion in a different way. This implies that this additional motion is stored in another dimension with a different type of interface that can cause this motion to be bound up in the particle separate from its three dimensional motion. When you put it all together, you get a hierarchical structure with the energy photon at the lower level with velocities in the first four dimensions and the matter particle with velocities in the first five dimensions. Motion can be transferred to or from the photon’s fourth dimension velocity directly by attempting to change its three dimensional velocity. Motion can be transferred to the matter particle’s fifth dimensional velocity by applying motion to its three dimensional composite velocity to increase its fourth dimensional velocity which can then pass it to its fifth dimensional velocity. The rate of transfer from the fourth dimension to the fifth dimension increases with an increase in the velocity in the first three dimensions. Because an energy photon can exist with about .511MEV and an electron can also exist with about the same .511MEV, it is apparent that velocity does not automatically transfer from the fourth dimension to the fifth dimension to generate a matter particle. This can be traced to certain angular components that must also be present due to the nature of the fifth dimensional interface to enable motion transmission. As a matter of fact the mass/inertia effect is greatly due to the fourth and fifth dimensional angular components. I hope this will be of help.
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John Merryman wrote on Oct. 30, 2008 @ 11:00 GMT
Paul,
"Time then is not a separate entity that somehow flows in one direction, but the measurement of motions through distances. It is the motions themselves that give us the sense of flow as they flow all around us. When you understand that it is the continuum of motions that are flowing, it is easy to see why they only go in one direction because a motion goes in one direction until it is acted upon by another motion and then it may go in a different direction or at a different motion amplitude as a result of the interaction. This pattern of motions and interactions between motions is continually happening all around us. The only way to go back in time (or at least appear to do so) would be to simultaneously reverse all motions in the universe and then reverse them again when they were back to the positions that they were in at the previous condition of all motions that you wanted to get back to. "
So time and temperature are emergent descriptions of motion.
As such, it seems the real confusion over time is that by modeling it as a fundamental dimension, the tendency is to view it as going from past to future. While Einstein disproved it is a fundamental dimension, he still seemed to model it as going from past to future, yet as an effect of motion, where each event is replaced by the next, what we view as this linear dimension of cause and effect is actually going the other way, from future potential to past circumstance.
Narendra nath wrote on Nov. 1, 2008 @ 13:57 GMT
Many comments have come during the past week and Carlo Rovelli is keeping a wise silence among some lengthy narrations. Let us make him feel easy to respond to what he feels like responding. The next post may be reserved for the author to clear the 'mess' getting generated on such a nice essay that attempts to simplify rather than complicate matters in understanding what Nature has done for us by creating the Universe, then our Earth and then trees/plants, animals and finally we humans with ability to comprehend it all!
Paul N. Butler wrote on Nov. 2, 2008 @ 06:25 GMT
John;
You are exactly right. Temperature is the measurement of the average free motion in an isolated system containing a large number of energy photons and, or matter particles and since these motions all have motion amplitudes and travel through distances they exhibit the property of time. It is just a more average statistical time structure than if you could look at each individual...
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John;
You are exactly right. Temperature is the measurement of the average free motion in an isolated system containing a large number of energy photons and, or matter particles and since these motions all have motion amplitudes and travel through distances they exhibit the property of time. It is just a more average statistical time structure than if you could look at each individual entity’s distance traveled and motion amplitude and then combine them all together to get the average distance and motion amplitude, which you would then use in the formula to get the average time. The result would generally be the same either way though if both approaches were completely accurate.
In analyzing the current state of man’s technology, I have found that several scientists have come to the conclusion that the current understanding of time is lacking, but they generally lack enough background information about the structure of the dimensional system and the entities that exist within it to get the full picture. For example, a common belief is that energy photons do not experience time because they are traveling at the speed of light. This is generally true as long as you restrict your study to those things that are only affected by the photon’s velocity in the first three dimensions because all photons have the same composite motion amplitude in the first three dimensions. If you make the speed of light equal to 1 in your motion amplitude scale then all photons would possess a motion amplitude value of 1, so you end up with a formula of T=D/1 or T=d. Since (in this limited context) time equals distance, there is no need for the separate derivative of time. The problem is that all photons don’t possess the same fourth dimensional motion amplitude. In practice most interactions between photons and other photons or matter particles are sensitive to the effects generated by the fourth dimensional velocity. All photons with the same fourth dimensional motion amplitude are truly identical and generate the same interaction effects. This is what has given rise to the idea of the quantum nature of energy in that all photons with the same frequency and wavelength seem to possess the same quantum (quantity) of energy as measured by their mass effects in interactions. This in reality is just saying, however, that they all have the same motion amplitudes generally in the same places that can be applied to the interaction. Because the electromagnetic spectrum appears to be a very wide range continuous analog progression from a very low fourth dimensional velocity (very low frequency and mass effect and a very long wavelength) to a very high fourth dimensional velocity (very high frequency and mass effect and a very short wavelength), there does not appear to be any true quantum effect. What is actually seen is that the continuously variable fourth dimensional velocity generates a continuously variable set of effects (frequency, mass effect, and wavelength) that are in lockstep with each other and the single variable that causes them (the fourth dimensional velocity). I know this is a little departure from your comment, but it came to mind and it does have to do with time and I have compassion for those who are struggling with the concept of the timelessness of photons so I thought I would try to give a little information about it that might (and I hope will) help. Now back to your regularly scheduled program.
You are right that from our perspective which allows us to only interact with a small portion of the motions in the world, the first step of interaction with one of us is for a motion to get into a position that will ultimately interact with that one. Through large numbers of high speed motion interactions our future is continually forming around us to ultimately generate our present. As an example, if someone could look at a given photon in your office, he might see it traveling away from you and assume that it would never interact with you and be a part of your present, but through many millions of bounces off of matter particles in the office walls and other things in the office it might bounce off of your desk just as you are looking at it and be a part of the image that you perceive as the appearance of your desk, thus becoming a part of your present when the interaction occurs. In practice we are bathed in a continuous bombardment of such high speed motion interactions and we are too slow to be able to observe and keep track of them all in real time so they appear to us to be a continuous overall flow of motion. Our senses tend to give us overall averages of the motions such as the way our eyes take the interactions with large numbers of individual photons and combine them to generate an average composite image. This is much like the difference between looking at and keeping track of each motion and motion interaction in a container of gas on the one hand and just inserting a thermometer into the container to read the average of the motions on the other hand, though maybe not quite as extreme.
Another thing that gives us our sense (especially of past and future) is the way that our minds work. Let’s look at the taxi example a little closer. In order to have called the taxi in the first place, you would have started by forming an intent to do so in your spirit. This intent could have been the result of a previous intent. As an example, while you are sitting in your chair, your body might send a pattern of motions to your soul that would cause your soul to generate the thought that you are hungry. These motions might be detailed enough to let your mind know that you need potassium. Your soul would then generate the thought that you need food with potassium and send it to your spirit. Your spirit would then generate the intent for you to get up out of your chair and walk to your kitchen and get and eat a banana from the place where you store them. This intent would be sent to your soul which would generate the needed thoughts that would then be sent to the necessary body parts to cause you to actually get up and go to the kitchen. At this point the light hitting your eyes from the place where you store your bananas tells your body that the bananas are gone. Your body sends motion patterns to your soul to inform it and your soul generates the thoughts and passes them to your spirit to let your spirit know that its intent can’t be performed as given and why. Your spirit then creates a new intent that is a sub intent to the first one, which is to call a taxi to take you to the store to get bananas and then passes the intent to your soul which generates the thoughts that are necessary and sends them to your body in the proper way so that your body will perform all needed motions. Of course things are not quite that simple. Part of the reason that we have this feeling of a continuum or flow of time is that our interaction with any given thing (the taxi in this case) can at any given instant have some interactions that are in the future, some that are in the present and some that are in the past. To show this point let’s suppose that your body gets tired of standing while you are waiting for the taxi so it sends signals to your soul that causes your soul to generate thoughts that it passes to your spirit to let it know that you cannot stand much longer. Your spirit generates an intent to solve the problem by sitting on a nearby bench. Your soul then generates the thoughts that cause your body to perform this action. At first when you are sitting there the taxi itself and the action of taking it to the store are completely in your future. To you, they are only in your future because you have stored the intent to take the taxi to the store in your mind and you have performed the planned steps leading up to your ability to take it when it comes, but it is still beyond the range of your senses. When the taxi gets close enough that you can see it your interactions with it begin to enter your present because you presently see it. At this point you may generate the intent to stand up and walk to the curb so you will be ready to get into the taxi when it gets to you and stops. After you have completed that action, it is stored in your mind as a completed part of your interaction with the taxi caused by the interaction of your seeing it coming down the street. You now have the taxi in your present because you can see it and it is still in your future because your planned action of getting into it can not yet be performed until it reaches you and stops. You also have your interaction with it in your past because you have completed the act of getting up from the bench and walking to the curb as a response to your visual sight of it. This joining together of past, present and future in our interactions with things can give a sense of continuity. Of course only the present motion conditions actually exist. We only have the concept of the past because our minds can store the present state of motion conditions and then can refer back to those stored records to give us an idea of how they have changed. If our minds did not have this ability we would be greatly disabled in our ability to make any sense out of the world because we would not be able to take advantage of knowledge gained by observing repetitive patterns in actions around us, which would mean no science. Every time we saw the sun come up it would be a new experience to us. This type of effect can actually be observed in people with certain types of dementia. If you were to suffer from the early stages of such a condition you might retain some very short term memory and usually you would still retain your long term memory. In our taxi example, you might get to the kitchen and see that you are out of bananas and call the taxi. You also might go outside to wait for it and if you got tired, you would likely sit down, but if it took the taxi a half an hour to get to your house, you would likely have forgotten the reason that you are out there on the bench by the time it gets there. You could have done the first things because in the early stages of the disease your long term stored memories would still be intact and your mind could still base actions on those records. As the disease progressed even these memories would be lost and you would become less able to intelligently act in reaction to the interactions that you encountered with the world around you. After awhile each time you tried to do anything you would have to try to figure it out again from scratch, and since there are usually more ways that you can do something wrong than there are to do it right, you would have many more failures than successes. Even if you happened to put your cup of tea in the microwave, closed the door and by chance hit the number 2 and it came out just right, you would not be able to retain that new knowledge until the next time, so you would be back to hitting a chance number again the next time. After awhile you would not even retain in your memory the microwaves purpose. You would live more and more in the present and you would even understand it less and less. It would more and more seem to be filled with random meaningless motions. Even if your mind could still think, you would not be likely to come up with much useful information without all the results of your past experiments with your surroundings and those that you would have also picked up from others. If you did come up with some good insight, it would not do you much good because you would have forgotten it by the next day. You would likely not bother with all the work after a while and give up.
If the stored records of previous motion conditions are more closely associated with our sense of a past, the ability to generate intents to fulfill purposes is more joined to our sense of the future. It is these plans that we imagine and then work to complete, but have not yet been completed that give us the concept that a predictable future is out there waiting to happen. The more successful we are at satisfactorily fulfilling our intents, the more real the future seems to be for us. If someone were to lose the ability to form intents to fulfill purposes, he would become a disconnected observer of the world with no ability to take actions to interact with the world around him.
There is much more, that can be said about the subject, but I have probably already offended Narendra Nath and for all I know possibly others by not only not keeping quiet, but also by making what has turned out to be my second lengthy narration in this contest space. It just happens that they are both in Carlo’s portion of that space. Since your comment to me was here before Narendra’s request though, I thought that you deserved an answer from me and thought it best to answer it here, so you would be sure to find it. In order to please Narendra, however, further comments can be put in the comment area for my paper “The Physical Nature of Time” if anyone is interested. Sorry Narendra and Carlo and anyone else also if I in any way have offended any. I will now wait until Carlo has had a chance to respond per your request Narendra before making any further comments here in Carlo’s space.
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John Merryman wrote on Nov. 2, 2008 @ 15:32 GMT
Paul,
I'm in general agreement with what you are saying. I'll add a further idea that's been rattling around my head on your thread.
Dr. E (The Real McCoy) wrote on Nov. 2, 2008 @ 19:37 GMT
Hello Carlo,
We miss you!
You write above, "Then there is a post on the waste of public money on research about time in quantum gravity. I take this seriously. Often at conferences I listen to talk after talk, and I wonder "is public money wasted here"? Maybe yes. But was it wasted public money the money that the Ptolemy's Kings put in Ptolemy's astronomy? Or that the Church put in...
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Hello Carlo,
We miss you!
You write above, "Then there is a post on the waste of public money on research about time in quantum gravity. I take this seriously. Often at conferences I listen to talk after talk, and I wonder "is public money wasted here"? Maybe yes. But was it wasted public money the money that the Ptolemy's Kings put in Ptolemy's astronomy? Or that the Church put in supporting Copernicus completely useless searches? Or that supported Maxwell and Faraday, Shcroedinger or Einstein? No, it clearly was not. Is there a way to chose a priori who will be next Dirac? No, there is not. Research needs courage, wasted time and money, false directions. The history of our civilization is the proof that all this money is not wasted, in my opinion.
Carlo"
How much government funding did Einstein receive as a patent clerk, when he wrote his five miraculous papers which revolutionized physics?
For that matter, how much money did "Ptolemy's Kings put in Ptolemy's astronomy?" And was this public money? Sometimes I feel like we've reintroduced Kings in the realm (empires) of science, so maybe that is actually a good analogy!
And how much money did "the Church put in supporting Copernicus completely useless searches?" And were Copernicus's searches really useless? I thought Copernicus liberated us from the geocentric universe! And how much government funding went to support "Maxwell and Faraday, Shcroedinger or Einstein?" Unless I miss my guess, they all made their monumental contributions *before* they received massive amounts of funding, if they ever did receive massive amounts of funding. I'll bet you $100 on this. :)
Then you write, "Is there a way to chose a priori who will be next Dirac? No, there is not." This is true, so why does so much funding go to so few who never really advance physics? And then after a few years of not advancing physics themselves, they are given 10x as much funding to pick out the next Dirac, or the next Einstein, or Bohr. It seems that these days, unlike the past, the less one advances physics on one's own, and the more one sticks with "communal" ideas that go nowhere, the more and more funding they receive, until we have entire empires--the richest scientific empires in the history of science, which have frozen progress in physics, while outlawing new ideas.
Science is more of an art than a science, and it always seems to advance in manners never before anticipated by the establishment, as Planck stated. One cannot legislate, nor vote on, nor dictate the advancement of science by fiat. "One cannot pray a lie," as Mark Twain once said.
"New scientific ideas never spring from a communal body, however organized, but rather from the head of an individually inspired researcher who struggles with his problems in lonely thought and unites all his thought on one single point which is his whole world for the moment." --Max Planck
And again we see the primacy of the honest individual in the classic, epic hero's journey!
"A hero ventures forth from the world of common day into a region of supernatural wonder: fabulous forces are there encountered and a decisive victory is won: the hero comes back from this mysterious adventure with the power to bestow boons on his fellow man." --Joseph Campbell
http://en.wikipedia.org/wiki/Monomyth
And the Nobel Laureate eocnomist F.A. Hayek agrees!
"The tragedy of collectivist thought is that, while it starts out to make reason supreme, it ends by destroying reason because it misconceives the process on which the growth of reason depends. It may indeed be said that it is the paradox of all collectivist doctrine and its demands for “conscious” control or “conscious” planning that they necessarily lead to the demand that the mind of some individual should rule supreme—while only the individualist approach to social phenomena makes us recognize the superindividual forces which guide the growth of reason. Individualism is thus an attitude of humility before this social process and of tolerance to other opinions and is the exact opposite of that intellectual hubris which is at the root of the demand for comprehensive direction of social purpose." –F.A. Hayek, The End of Truth, The Road to Serfdom
Not only do the contemporary antitheory empires concentrate epic amounts of funding into a small group of physicists' hands, but by and by that group does not only not fund the advancement of physics, but it funds Ph.D.'s and postdocs to go forth and actively ban, censor, castigate, and attack new ideas, often anonymously, so as to please their elder kings and shore up their funding. Is this a prudent use of funding? Would we not be better off without such funding? Getting rid of this funding would remove the incentive for joining groupthink and regimes, along with the incentive to ignore and/or attack simple theories rooted in logic and reason, so as to keep progress in physics frozen.
Carlo--since, as you say, one cannot predict the next Dirac, why not distribute smaller amounts of funding to a greater number of physicists? Would this not make sense from both a statistical and moral standpoint, and lessen the probability of kingships and empires and their hired mercenaries who oppose the advancement of physics, thusly freezing its progress?
Even though the Greats have been banned from the Academy, every physicist ought read George Orwell and Nobel Laureate F.A. Hayke, who expound on how groupthink, in the absence of the moral appreciation of the Truth, leads to tyranny:
http://en.wikipedia.org/wiki/Animal_Farm (about when the LQGers overthrow the String Theory Regime and institute their own government, where all anti-theories are equal, but some are more equal than others)
http://en.wikipedia.org/wiki/Nineteen_Eighty-Four (about a young man working at the Ministry of Physics and a young woman working at the Ministry of Corporate-State Curiosity)
Well, no man is an island, and physics has ever been advanced by cordial conversation in the context of rigorous honesty and a humble acknowledgement of empirical facts. Einstein and Bohr disagreed often, but yet they had a deep respect for one-another, and I highly recommend the perusal of their converstations! Where would be be without the disagreements between Einstein and Minkowski, between Bohr and Einstein, and between Pauli and just about everybody? Contrast their exalted dialogues to the snarky dialogues in the modern string-LQG wars (and the 10x snarkier attacks lauched against MDT), and the perhaps even more troubling complete *lack* of dialogue for topics and approaches transcending those two "theories" which might not even be *physical* theories after all.
Again, the Nobel Laureate Max Planck writes,
"New scientific ideas never spring from a communal body, however organized, but rather from the head of an individually inspired researcher who struggles with his problems in lonely thought and unites all his thought on one single point which is his whole world for the moment." --Max Planck
And yet today's science is dominated by "communal" theories bolstered by multi-million-dollar media teams. And again, these theories aren't really *physical* theories. They are often merely "not even wrong"--and they defend their not-even-wrongishness unto the death, as it provides the center and circumference of a groupthink regime, which in turn guarantees infinite funding, accolades, press, televised mini-series, and awards for a small set of "leaders" heading anti-theory regimes.
Planck also wrote, "Eine neue wissenschaftliche Wahrheit pflegt sich nicht in der Weise durchzusetzen, daß ihre Gegner überzeugt werden und sich als belehrt erklären, sondern vielmehr dadurch, daß ihre Gegner allmählich aussterben und daß die heranwachsende Generation von vornherein mit der Wahrheit vertraut geworden ist."
Translation: "A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it."
Once upon a time new theories were opposed by established scientists and established science. But today, new theories are opposed by established anti-theory bureaucracies and established bureaucrats, which have done little, if anything, to advance or contibute to actual science. So walking into town with a new theory is more akin to Galileo standing before the Inquisition.
Bohr and Gamow loved Westerns--I woudl do anything to watch some Westerns with those guys. Westerns always open the same way. The lone cowboy--the high plains drifter--drifts on into town, and immediately the boss's lowly gangsters and postdocs mock, belittle, and intimidate him, just like how it goes down in today's "communal" realms of non-physics and anti-theory regimes, which are always run out of the saloons with the crooked dealers.
This is what it sometimes feels like talking about Moving Dimensions Theory, when I ride into town on a mule, as I don't have the funding to buy the BMW--the preferred ride of the anti-theorists I have heard:
http://www.youtube.com/watch?v=ADzFve-tKnU
Director Sergio Leone was a genius! Perhaps you saw some of his films in the original Italian! You can see how Sergio has that Homeric poetry in his soul.
It seems too many physicists have forgotten the Hippocratic Oath--"first, do no harm."
Perhaps we ought contemplate a oath for scientists!
http://en.wikipedia.org/wiki/Hippocratic_Oath_for
_Scientists
So, in light of all this, Carlo, I'm thankful for this conversation and to fqxi for providing this forum which brought us togetehr!
MDT provides opportunities for novel research programs and curriculums--for new directions and exalted pursuits in physics, philosophy, and knowledge--based upon the foundational works of physics. And on a deeper level, the "heroic spirit" the program exalts could find use across all realms in academia and throughout our economy, in which far, far too many people profit by saying one thing and doing another--activities which have lead to our current financial crises and familial, cultural, and scientific delcine.
MDT predicts all of relativity from a simple postulate and equation that also provides *physical* models for entropy, time, and all its arrows, quantum entanglement and nonlocality, and all the dualities--space/time, energy/mass, and wave/particle. Not bad for one small equation: dx4/dt = ic, which offers a *physical* unification across all realms of physics, tying together entities as diverse as quantum entanglement and the timelessness of the photon, while presenting insight into a novel physical facet of our universe--the fourth dimension is expanding relative to the three spatial dimensions.
Finally, Carlo, you write, "Research needs courage, wasted time and money, false directions."
Well, I agree Research needs courage. Classic, cowboy courage!
Courage is a kind of salvation. --Plato
Moral excellence comes about as a result of habit. We become just by doing just acts, temperate by doing temperate acts, brave by doing brave acts. --Aristotle
O friends, be men, and let your hearts be strong,
And let no warrior in the heat of fight
Do what may bring him shame in others' eyes;
For more of those who shrink from shame are safe
Than fall in battle, while with those who flee
Is neither glory nor reprieve from death.
- Homer's Iliad (bk. V, l. 663),
All serious daring starts from within. --Harriet Beecher Stowe
Moral cowardice that keeps us from speaking our minds is as dangerous to this country as irresponsible talk. The right way is not always the popular and easy way. Standing for right when it is unpopular is a true test of moral character. -- Margaret Chase Smith
If you lose hope, somehow you lose the vitality that keeps life moving, you lose that courage to be, that quality that helps you go on in spite of it all. And so today I still have a dream. --Martin Luther King, jr.
Whatever you do, you need courage. Whatever course you decide upon, there is always someone to tell you that you are wrong. There are always difficulties arising that tempt you to believe your critics are right. To map out a course of action and follow it to an end requires some of the same courage that a soldier needs. Peace has its victories, but it takes brave men and women to win them.
--Ralph Waldo Emerson
But none of the physicists you listed would agree that research necessarily needs "wasted time and money, false directions." It is not in a true physicist's nature to wish for wasted time amd wrong roads, as we know how fleeting life is.
All the wasted money, which is wasted so flippantly these days--so pridefully--is a vast and resounding insult to all the honest postdocs, grad-students, and hard-working professors, who are never. never paid enough.
And so it is that I propose a more equitable distribution of grants, for as long as "money is wasted," and "nobody can predict the next Dirac nor Einstein," why not approach the world, and one's fellow physicists, with more humility, kindness, and common courtesy?
For "humility, kindness, and common courtesy," cost nothing extra, and will go far further in returning the classic, heroic spirit to the realm of physics--the spirit by which physics has ever advanced, than will hundreds of millions of dollars, which cannot buy one iota of truth, any more than it can buy the soul.
An education obtained with money is worse than no education at all” --Socrates
"Humility, kindness, and common courtesy" will do far more to advance knowledge, wisdom, and culture than vast amounts of funding for regimes that have made a God-King of failure, and now bolster the black holes of anti-theories with hired mercaneries who play little games of censorship, snark, and PR hype, while penning 10^99 meaningless, indecipherabel papers. I am not convinced that such entities are necessary to the advancement of science, and I would, in fact, postulate that they are antithetical to the adavancement of science and culture, which find merrier companionship in truth, logic, reason, simplicity, honesty, and a keen appreciation for and dedication to *physical* reality.
For know this:
And yet it--the fourth dimension--moves! And its movement hath liberated us from frozen time, liberated us from the block universe, and liberated us from frozen progress in theoretical physics!
Change, my friend, has been woven into the fundamental fabric of spacetime, where it needs to be! For change encompasses every physical realm! There can be no measurement without change, and thus there can be no physics without change!
O happy day! A new, hitherto unsung universal invariant has been bestowed upon us--the fourth dimension is expanding relative to the three spatial dimensions at c! dx4/dt = ic!
And this motion hath taken us to a brave, new heroic age!
http://en.wikipedia.org/wiki/E_pur_si_muove
E pur si muove!
Now and Forver!
And unless I miss my guess, we are in for one wild night. . .
Best,
Dr. E (The Real McCoy)
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Narendra Nath wrote on Nov. 3, 2008 @ 06:52 GMT
Paul Butler, John Merryman and Dr. E have dominated the scene since my posting of Nov. 01 seeking response of dear author, Prof. Carlo Rovelli to similar lengthy postings prior to November 01. He is still keeping his silence for reasons best known to him.
In the series of essays on 'Nature of Time', we have had two unique theories presented, one TGD by Dr. Matti Pitkanen and the other by the other MDT by your self. Where do we stand to understand the physical universe with respect to the non-physical entity called 'consciousness'. i will appreciatively request Prof. Rovelli to come out with his responding post ,clearing the air filled with lots of historic quotes and lengthy comments, no offence meant towards such postings either!
Bob wrote on Nov. 9, 2008 @ 10:23 GMT
Carlo, I have a question about unitarity. In the timeless picture you propose there is no unitarity, right? Does this mean that probability conservation can be violated? Bob
Carlo Rovelli wrote on Nov. 9, 2008 @ 10:42 GMT
Dear Bob,
thanks for the question, which is very appropriate. Let me give a dry answer first, and then explain:
> In the timeless picture you propose there is no unitarity, right?
Right: more precisely, there is no unitarity in the usual sense.
> Does this mean that probability conservation can be violated?
No: probability conservation is not violated.
Let me explain. In usual quantum theories, unitarity is the request that the change of the state *in time* is given by a unitary operator. It follows that probability is conserved *in time*. In a theory in which there is no preferred time variable, this request obviously looses its meaning. This is why unitarity in the usual sense is not present in the timeless formulation. Nonetheless, probability must be "conserved". This means that the probabilities of all the possible specific-measurement's outcomes predicted by the theory must sum up to one. Unitarity in *this* sense must of course be implemented by the timeless theory, and it is.
The answer is different in the statistical context. In this context, thermal time emerges, and therefore we have a unitarity requirement again. In this case, the evolution in thermal time turns out to be unitary by construction.
Thanks also for bringing back the discussion to the actual content of the essay. I do not think that this forum is the proper place for discussing alternative points of view, especially if discussed in other FQXi essays, or issues which are too general.
Carlo Rovelli
Narendra wrote on Nov. 9, 2008 @ 15:15 GMT
Nov.03 post awaits your response, Carlo. Hopefully , u consider it appropriate for your essay! Parallel between TIME & temperature seems a significant issue. Will you like to give weight to space/time concept over the reality of gravity?
Probability considerations require complete randomness in physical processes. What do you feel if i say ' Order contains randomness but not the reverse of it '?
Dr. E (The Real McCoy) wrote on Nov. 9, 2008 @ 19:18 GMT
Hello Carlo,
Above you write, "Then there is a post on the waste of public money on research about time in quantum gravity. I take this seriously. Often at conferences I listen to talk after talk, and I wonder "is public money wasted here"? Maybe yes. But was it wasted public money the money that the Ptolemy's Kings put in Ptolemy's astronomy? Or that the Church put in supporting Copernicus...
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Hello Carlo,
Above you write, "Then there is a post on the waste of public money on research about time in quantum gravity. I take this seriously. Often at conferences I listen to talk after talk, and I wonder "is public money wasted here"? Maybe yes. But was it wasted public money the money that the Ptolemy's Kings put in Ptolemy's astronomy? Or that the Church put in supporting Copernicus completely useless searches? Or that supported Maxwell and Faraday, Shcroedinger or Einstein? No, it clearly was not. Is there a way to chose a priori who will be next Dirac? No, there is not. Research needs courage, wasted time and money, false directions. The history of our civilization is the proof that all this money is not wasted, in my opinion. "
You say that research needs "wasted time and money."
Above you also kindly write, "Dr.E. ha posted a friendly note, arguing that perhaps gravity needs not to be quantized, quoting Dyson on this, and pointing out his "Moving dimansion theory". I thank him for the indication. I'll look at it (I suppose this is one of the purposes of the Forum)."
I never heard back from you regarding Moving Dimensions Theory and its mechanism for the emergence of time and change; as well as the theory's weaving of change into the fundamental frabric of spacetime. --http://fqxi.org/community/forum/topic/238
To date, quantum gravity research, including string theory and numerous other ventures, has recieved hundreds of millions of dollars over the past thirty years, with nothing to show for it. So it is, Carlo, that you justify this spending of hundreds of millions with the conjecture that that research needs "wasted time and money."
Well, I was wondeirng if you might have a few minutes to read the Moving Dimensions Essay, and if you could perhaps opine on how much money it ought to receive.
I think that you will find it to be worth a few million, if not more.
While quantum gravity regimes generally ban the asking and answering of foundational questions (string theory even ignores the foundational fact that spacetime bends an dmoves), and while the pursuit of quantum gravity has not yet resulted in any *physical* postulates nor *physical* equations, MDT asks foundational questions and answers them with a *physical* model--with a *physical* equation--dx4/dt=ic, and a postulate: the fourth dimension is expanding relative to the three spatial dimensions.
All motion and tiem rests upon this fundamental universal invariant--the fourth dimenion is expanding relative to the three spatial dimensions: dx4/dt = ic. Every object moves at but one speed through space-time--c. This is because space-time moves at but one speed through every object--c. Catch up with the fourth expanding dimension, and you'll be going close to c relative to the three spatial dimensions. Remain stationary in the three spatial dimensions, and you'll be traveling at close to c relative to the fourth dimension. And isn't it cool that the faster an object moves, the shorter it is in the three spatial dimensions? This is because it is physically being rotated into the fourth dimension--the fundamental source of all motion by its never-ending motion, which sets the universe's maximum velcoity at c.
Relativity implies a frozen, timeless, block universe. But as Galileo said, "Yet it moves!" *Why* is this? Because dx4/dt = ic! And the spherically-symmetric expansion that the expanding fourth dimension manifests itself as--this smearing of locality--jives perfectly with the motion of a photon as well as its nonlocal properties, setting its velocity to c independent of the source and rendering it timeless and ageless--stationary in the fourth expanding dimension, which would also explain entanglement with other photons with which it once shared a common origin! And we also get a *physical* model for entropy and time and all its arrows, whowing that they emerge from a deeper *physical* principle.
Well Carlo, I hope that you do not find the answering of foundational questions regarding the emergence of time off-topic in a forum at the "foundational questions institute" that is devoted to the nature of time.
Thanks for your time! I hope that in reading the MDT essay it is not wasted, as so much time (and money) has been tragically wasted in the pursuit of quantum gravity, which has displaced *physical* physicists from the academy, leading to our current crises, the dominance of antitheory regimes, and the absence of progress in theoretical physics over the past thirty years. I just read somewhere someone referring to your generation as "the lost generation" of physics. I will try to find the source. It is curious that "the lost generation" is the same thing as the "best-funded generation."
Perhaps, in the realms of art and science and culture, even more important than money is matching word and deed, and following through on reading an essay one promised to read. Or perhaps it is too late for the "lost generation" to change the path they are on, and prizes and titles and wasted money are worth more than honor, integrity, and immortality on the scientific, *physical* battlefield.
"Politics is for the present, but an equation is something for eternity." --Albert Einstein
And so I'll have to bet on dx4/dt=ic .
Thanks for your time & best,
Dr. E (The Real McCoy)
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Yuri Danoyan wrote on Nov. 9, 2008 @ 23:20 GMT
For best understanding how the Universe working need some time switch of the Time.TIME OUT FOR TIME.
F. Le Rouge wrote on Nov. 10, 2008 @ 15:11 GMT
I do agree with J. Merryman's refutation above that temperature is not a different kind of scale compared to others based on motion, sun-dial, space, mechanical clock, seasons, Galileo's drops of water, etc.
And I do agree with Narendra Nath objection against randomization. Multiplying static events is not more predictive than dividing them would be past or memory. Dynamics cannot be based on an algebraic 'function'.
Therefore the comparison between 'time' and 'flow' is not 'intuitive' as Dr Rovelli says but a reflexive specific idea on Time that is not shared by many old or new scientists from the Greek Science until today. If this reflexion of Dr Rovelli on time phenomenon is not coming from metaphysics, as it is not physical either, what is it? Just his opinion?
Three quotations of C. Rovelli's essay to prove that Dr Rovelli is mixing physics with arithmetics or algebra:
- CR: 'Familiar physical quantities that disappear when moving to a deeper level of description'
- FLR: Quantities are not physical but legal; they do not 'disappear' but they just change as Fahrenheit are becoming Celsius degrees when you cross the fronteer; the example taken is a 'surface of a liquid': water is 'physical' but not its abstracted 'surface' which is only a poetic or algebraic idea of liquid matter.
- CR: 'Experience shows that we can find mathematical laws characterizing sequences of events (This is the reason we can do science.)
- FLR: 'Sequences of events' are still mathematical laws. Here the argument is redundant and Science based so on tautology. I am not surprised because Central Limit Theory is obviously a tautology too.
- CR: 'In nature, there is no preferred physical time variable t'
- FLR: For sure because there is no 'variable' in Nature. Here is the reason why some scientists think that the problem is to find the adequate scale to make predictions.
The good question is not to use a better ratio, to find the adequate arrow or scale including time but the problem is adequation or equivalency. Why is the Modern Science using so (blindly) interchangeable ratios that drive to exchange Nature or matter with variables like a video-game player hesitating between the virtual reality of his screen and the 'real reality' backwards.
The time subtle 'phenomenon' has become in Modern Science obviously a 'happy hour' for this puzzle of carrots and turnips and their packings together, in Einstein's Theory as in Quanta Physics based on a pre-determinated factor time too.
Yuri Danoyan wrote on Nov. 10, 2008 @ 20:45 GMT
Time- anesthesia help better understanding anatomy of the Universe.I think is right time and right place forget about time.
Narendra wrote on Nov. 11, 2008 @ 06:47 GMT
Dear FLR & Carlo,
i tend to agree with most of the points made above by Flr. Huge posts by John Merryman & Paul Butler are mere elaborations of their respective view points in their essays.i personally feel that this competition is not about individual egoism but more about expanding paradigms in science. Also, the latter is not possible if we make scientific methodology static for all times to come. Thus, there is need to broaden one's outlook and possibly make it tend towards the all-encompassing nature, the storehouse of total knowledge. Taking assistance of the non-physical concept of 'consciousness' needs to be welcomed, as our brain/intellect is more than pure physico-biological system.
There are indications about its power in the ancient literature that now requires systematic evaluation based on scientific tools developed. in my essay, i have indicated about such holistic considerations based on my own personal cum professional experience.
Paul N. Butler wrote on Nov. 15, 2008 @ 06:14 GMT
Narenda;
I see that you have mastered some of this world’s propaganda techniques that are often used by those in low level civilizations to marginalize and attempt to discredit the works of others that one feels threatened by, or does not agree with, or does not understand. These techniques are usually used by those who do not have a good counter argument because those who do have the...
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Narenda;
I see that you have mastered some of this world’s propaganda techniques that are often used by those in low level civilizations to marginalize and attempt to discredit the works of others that one feels threatened by, or does not agree with, or does not understand. These techniques are usually used by those who do not have a good counter argument because those who do have the true argument find it much more effective to just present the true argument which will show the invalid argument to be false. I believe that your argument is based on the following concepts. 1. John Merryman’s and my posts are too long. 2. Our posts are mere elaborations of our respective view points in our essays. 3. You believe that individual egoism is involved (name calling propaganda device). Let me answer your points in order.
First my comments are long because my intent is to present information in such a way as to make the points as clear as possible and this can require information space. I like to use visualization techniques to allow those that are on the reception end to actually see the concepts in their minds if they have the ability. This also takes information space. I have made a total of four comments in the total contest area including this one. One is on my own paper’s comments space and three (including this one) are on this paper’s space. Although these individual comments may be long, my total use of the contest’s comment space has been less than some others. On the other hand, John Merryman’s comments on this paper’s space have generally been very short (often shorter than yours). At the same time you did not mention a problem with Dr. E’s comments (in this comment space) which are longer than mine and also more in number. So your point number one does not agree with the evidence to any significant degree.
Your second point is basically true, however, it is also generally true of all of the comments in the contest space. Each contestant is trying to get his view points across to others for one reason or another and comments by contestants tend to be in line with their current levels of knowledge and points of view. If another contestant’s view is close to yours, you can just congratulate him on his point of view, but doing so is just another way of bolstering your own point of view because of its similarity to yours. So although this point is true it is a non-issue because it is a common trait of all commentators.
The third point is a harder one to address because it goes to intent and a person’s intent or purpose in generating the thoughts that are expressed externally such as in these papers and comments is often not clearly seen by analyzing the thoughts that are presented. This leaves a lack of visual evidence that can be readily pointed to when trying to refute such attacks on one’s integrity. All I can do here is to reiterate what I said in my Author Bio, which is that my intent is to attempt to pass on to others some of the information that I have amassed over the years because it would seem to be a waste for it to be lost to man when I leave this world. Not that I am anyone special in this context. I believe from what I have read of your material that you may have a similar intent, as may be the case with others also. Although they may be important to some, to me the prize money and the glory of winning are not important. It is getting across the information that will allow the advancements in science that are necessary to avoid a great loss of life and also will provide a better life for people in this world in the future that is important. It saddens me greatly that so many put their immediate gain in fame and money ahead of the needs that are so apparent in the world around them. At the same time, I do realize that the current funding system (which rewards those who are most closely aligned with the current predominate theories and tends to marginalize those who have new insights that diverge to any degree from the concepts in those predominate theories) can make it difficult if not impossible for a scientist that must make his living from his work to make a reasonable living for himself and also get new concepts into the mainstream information channels where they can be taken seriously, analyzed, and utilized (if found to be true) to advance the level of scientific knowledge. The easy way to success in the current system is to just look for some overlooked niche in the current theories and exploit it. That is why I found it interesting to test this contest to see if it truly will reward those who offer new, different, and useful concepts or whether it will just be another promotion of those with the different concepts that are the most closely aligned to the mainstream.
To answer more particularly about my intent in my first comment to Carlo, it was to show him that he is on the right track in trying to get away from the T time function that goes back to a comparison with a time standard and the belief that time is some physical dimension, but that he also must keep in mind that the true meaning of time, which is the relationship between distance and motion amplitude is not something to be avoided because it is a real part of our world and to try to get away from it would result in a theory that would not accurately describe the real world. I also showed him that his use of thermal concepts do indeed include to true meaning of time because when one measures temperature, one is actually getting an average value of a large number of entities traveling through various distances with various motion amplitudes. I went on to show him that he could get a more accurate actual value that can be applied to an individual interaction without the averaging effect by just replacing the time based R term in the T=D/R formula with a motion amplitude function that is based only on a comparison with a selected standard motion amplitude level. This could greatly simplify his work and give him new insights that are currently hidden to him because of his current approach. Of course one must also understand the base structure that generates quantum effects to go beyond the current quantum based theories, but he is on the right track as far as his treatment of time is concerned.
My second comment in this space was to answer John Merryman’s comment concerning my first comment to Carlo. I admit that I got sidetracked in that thoughts about the timelessness of photons came to mind so I put them down. Maybe they came from the universal consciousness (or God if you prefer). It could be that someone needed that information at that time and so it was given through me. I thought it best to answer John’s comment on this space because his comment was placed on this space and also because if anyone else who had seen his comment was interested in the same thing, he would be able to see it too. I did, however, redirect any further comments to me to my space so as not to offend anyone more than necessary. I also said that although I felt it appropriate to answer John’s comment because he had made it before your request for silence, I would not make any further comments on this space until Carlo had responded. I kept that promise and would probably not have commented further on this space yet if at all except to respond to your negative remarks about John and me.
You are right that consciousness is more than the pure physical structure that is currently able to be seen and scientifically understood by man in this world. That is because although the body and that portion of the soul that interfaces with the body is composed of matter and energy structures that can be observed and scientifically studied, the spirit and that portion of the soul that interfaces with the spirit is not composed of matter and energy as known to man in this world, but is of another source that is not known by man in this world. This means that you might be able to determine a man’s thoughts from observation of his brain’s matter and energy structures and patterns, but you would need to have a much higher level of knowledge to be able to determine his intents that generated the thoughts. Given man’s present rate of progression, this is not likely to happen very soon. That is all of the information in that area that I am currently releasing (any comments to me can be addressed to my paper’s page) and as this is turning into another dreaded huge post, I should and will end this post now.
view post as summary
Narendra wrote on Nov. 15, 2008 @ 06:58 GMT
Dear Paul,
As this is a post on Carlo's essay, may i just go to your essay to respond pleasantly and cheerfully to you comments on the above posting on Nov., 15.You appear to object to the comment i happen to make on very long postings by some authors/commentators!
Paul N. Butler wrote on Nov. 17, 2008 @ 08:02 GMT
Narendra;
Yes you may (as I mentioned at the end of my previous comment to you, in order to minimize any offence to Carlo)Sorry Carlo. This is me doing a very short comment.
Narendra Nath wrote on Nov. 17, 2008 @ 12:53 GMT
Carlo's wise silence continues, may well be for the good of us all, provided we contemplate!
Myke wrote on Nov. 18, 2008 @ 16:35 GMT
Hi all, contemplate indeed! I can see where Carlo is coming from, but the relational elements still require creation in a real (non-virtual) context. The creative cascade from my quantum pseudokinematics (QPK) can be seen as giving either spatial or temporal locations in a constructive context. It just depends on how you like to define the concepts. Even if a quantity is ratiometrically hidden (caused to vanish) it still intrinsically exists, to ghost its consequences...
F. Le Rouge wrote on Nov. 24, 2008 @ 17:51 GMT
'Non-virtual' or 'No Time': same idea. One can define on this forum three kinds of people:
-Those who do admit the idea of virtual matter and are 'ready to travel in Time';
-Those who think Matter is both virtual and material and have as many subjective ideas to make the link between their 'informational matter' and their 'strong matter'. Rovelli's subjective idea is 'thermic scale' because it gives more solid feeling than the informational Space and speed-scale that Einstein introduced in Physics;
-Those (me) who think that matter can be seen as an informational thing but is not at all. So that it is necessary to let the binary Algebra on one side because it is responsible of the mixing of real Physics with virtual Physics that cannot allow to understand Matter better.
Narendra Nath wrote on Nov. 25, 2008 @ 07:49 GMT
Dear Carlo,
Considering the merit of your essay on' Forget Time ', i posted many posts between Oct 22 and Nov.11. These were all short ones but in my view it had points directly relevant to your theme essay. However, you preferred not to respond to the specific queries raised therein. May be, you prefer to adhere strictly to your own contents of the essay and any alternate line of approach meets with your silence! May i request finally that you kindly consider the alternates mentioned with your own reasoning for rejecting them all. That will add to the spirit of this open essay contest on ' The Nature of Time '. Otherwise it so appears that you want to reject the theme itself!
Cristi Stoica wrote on Nov. 29, 2008 @ 14:44 GMT
Dear Dr. Rovelli,
I enjoyed reading your essay.
1. A century ago, physicists tried to make the laws of Physics compatible with the principle of relativity. To do so, they had to “forget time” as a special direction in space-time, to obtain the covariance.
Now, you remember us to “forget time”, proposing an interesting way to do this for Quantum Mechanics.
2. In General Relativity, the time can be easily recovered. Any localized enough system has already a proper time – the natural parameter on that curve. What is missing is the direction of time (positive or negative), and we use for this the thermodynamic time arrow.
3. You propose a thermal time, which also comes with a thermal time arrow. Sometimes, this thermal arrow points in the same direction as the thermodynamic arrow, while in other cases, it doesn’t.
A. For instance, in your example, the Friedmann universe has a special symmetry, which singles out a time direction anyway. Because of this symmetry, I think that is hard to give a general definition of time which differs, on this particular example, from the Friedmann time.
B. But we can easily provide counterexamples. A particle moving through a medium has a proper time, while the thermal time of the total system may be very different from it.
Cristi
http://fqxi.org/community/forum/topic/322
F. Le Rouge wrote on Dec. 1, 2008 @ 18:08 GMT
- ‘Relativity Theory’ is not a ‘Revolution’ as Dr Rovelli says and the new idea that the algebraic conventional reference is more real than reality itself was introduced by I. Newton, R. Descartes, C. Huygens, P. Fermat before Planck, Poincaré and Einstein.
The idea that ‘Subjectivity is stronger than Objectivity’ is the same idea. Symmetry, Infinity, Eternity are as many subjective approximations of Nature that is not symmetric, infinite, eternal, contrarily to Einstein theory, CLT, Quadratic equations, cells and vectors of time/space…
This is the reason why the subtle Time, so ‘intimate’ that Dr Rovelli wants to let it on one side with a lot of decency, this is the reason why the Time took bit by bit the lion’s share from C. Huygens until the Travel in Time illusion.
In Descartes 'Natural Philosophy' for example you still have all the stuff: ‘Squaring the circle’, ‘Paradox’, ‘Trigonometry’, ‘Translation of Geometry in Algebra’ and guess what? ‘String Theory’ too.
- Galileo’s or Newton’s pendulum/is not giving any 'special direction' as C. Stoica is suggesting here. Clock is just a rythm, a symmetric oscillation phenomenon and a speed too, that is not the same if you are in the mountain or in the flat country. Galileo used a pendulum for a practical reason in his ballistic experiences although Newton seem to ‘believe’ in the clock reference somewhere.
About the thermic scale: water is not boiling at the same temperature depending from the altitude too.
- Let’s take the Snowboard image: as a group of snowboarders would love to ski. Some want to forget the board material, others the snow matter, but no one the idea of snowboard itself! I do not even speak about dreamers that believe that video games are more real than evrything...
Dimi Chakalov wrote on Dec. 2, 2008 @ 06:41 GMT
Hi Carlo,
Your Conclusion #4 is "to forget the notion of time all together, and to define a quantum theory capable of predicting the possible correlations between partial observables", which perhaps is related to your statement that "general relativity challenges strongly our intuitive notion of a universal flow of time."
But you stressed in gr-qc/0604045 v2 that "the proper time [tau] along spacetime trajectories cannot be used as an independent variable either, as [tau] is a complicated non-local function of the gravitational field itself. Therefore, properly speaking, GR does not admit a description as a system evolving in terms of an observable time variable."
Ergo, GR cannot reject something that is beyond it. Perhaps it would be a good idea if you consult Prof. Karel Kuchar.
Dimi Chakalov wrote on Dec. 2, 2008 @ 08:21 GMT
P.S. Following the line of reasoning adopted by C. Rovelli, in a fundamental description of nature we must "forget" 3-D space as well, because there is noting in GR to reveal some mechanism producing a spacelike hypersurface with respect to which people talk about "time", as in ADM hypothesis on "the dynamics of GR". In this sense, GR cannot reject something that is beyond it, as stated in my preceding post. Nor can GR explain the apparent time-orientability of spacetime, which also is beyond its applicable limits.
It is completely unclear to me how Rovelli's "patrial observables" can shed light on something that is beyond both GR and QM.
It seems to me that Rovelli's recipe for quantum gravity is this: take Quantum Mechanics and General Relativity in their current formulation, with all their well-known problems, blend them into some new theory with "patrial observables", and hope that the problems of QM may be solved from GR, and the problems of GR may be solved from QM. Don't try to solve any of the initial problems of QM and GR beforehand. Just hope and pray that the "good parts" from QM and GR will cure all problems.
Picture this: you have a car (QM) which runs quite well on some roads, but fails miserably on some essential roads, and a helicopter (GR) that also runs in some favorable weather conditions, but is totally useless in bad weather. Take the car and the helicopter, and build a brand new vehicle, which will run better than the car and fly better than the helicopter, and will also allow you to dive deep into the ocean, as a perfect submarine.
Is this Rovelli's recipe for quantum gravity?
F. Le Rouge wrote on Dec. 2, 2008 @ 17:08 GMT
'Pray' is the good word in this 'Time Chapel', Chakalov.
I suggest another metaphor: Time is God but Carlo R. does not believe in God and saint Einstein anymore. So he kills the God but keep the ornaments and the Folklore, the saint statue, not to offend people around too much.
Eckard Blumschein wrote on Dec. 2, 2008 @ 23:02 GMT
Dr. Rovelli,
Please do not mistake it as a personal attack if I ask you to explain step by step how the imaginary unit in your equation (5) relates to our real world.
While we seem to agree on rejecting the widespread belief in an a priori existing time extending for good from eternity to eternity (-oo < t < oo), my suggestion "Let's Benefit from Special Mathematics for Elapsed Time" intends to focus on fertile rather than futile stuff. Maybe I am wrong?
Look at http://home.arcor.de/eckard.blumschein/M283.html for more refutable details.
Regards,
Dr.-Ing. Eckard Blumschein
Petr Frish wrote on Dec. 3, 2008 @ 12:40 GMT
One thing I like about this Fx contest is certain time inversion: Normally, you read what was published on the topic, and You may find that you can add an original bit to it. Here it seems, one can submit something, and then find out (as a pleasant surprise) that someone already had a similar impression. It may be an illusion, since the terms used do not seem to be strictly defined, but it still feels good. En example:
When you say in your essay (page 3) '.. and notions such as “the quantum state of the system at time t” are quite unnatural in a general relativistic context...' I am happy, to realize I am not the only observer who feels that way.
You suggest an opposite remedy, 'to forget time' then me 'to split it in two' in "One time is not enough" but I am still pleased.
I am still reading all the comments, but I already find another 'pearl of wisdom' - I man something I agree with :-)
'"flowing" time are related to thermodynamics: only in a thermodynamical situation we may have irreversibility, for instance, and we may have memory.'
I would like to make it stronger = a conjecture: Flowing of time a a property of the observer. Any decent observer
of course has a memory. An object (complex particle with no memory) does not experience a flow of time. etc
Luigi Acerbi wrote on Dec. 3, 2008 @ 23:35 GMT
I completely agree with the basic idea expressed in this essay. Let us forget about time!
In fact, I believe that if we want to understand the deepest laws of physics we have to get rid of all the unobservable quantities -- finding all the "illusory" macroscopic degrees of freedom and then quotienting them away (just like GR and gauge theories do).
Quoting Zurek, this may be called a part of the "epiontic" approach to physics (which I review in my essay).
Thanks for your inspiring work.
L. Acerbi
(The Epiontic Principle..., http://fqxi.org/community/forum/topic/333)
F. Le Rouge wrote on Dec. 4, 2008 @ 11:42 GMT
Including conventional Time as Superstring theoricians or C. Rovelli do can be seen as much as 'forgetting Time' than 'prescribing Time'.
Second expression is more logic until String Theoricians or Dr Rovelli do not prove that Time is not only a conventional idea but a material one that is grounding the dose of Time. A proof that is obviously lacking here, although the question was -remember- about the NATURE OF TIME.
If a 'pure theorician' does not want to prove that Time is 'something', what I can understand, in this case he MUST prove that conventional Time is dynamics.
Are Boltzmann or Planck telling us anything about the dynamism of Energy or Matter? No, they are just 'quantifying it' that is to say 'squaring the circle'.
We do not know anything more about temperature, energy or matter after Planck than before. Worst than that:idea is growing from here that ballistic measurement (the Wave) is part of Matter although it is only part of ballistic.
To make a comparison: exactly as Walras thought that his economic Diagrams grounded on thermodynamism were part of the Economy.
Eckard Blumschein wrote on Dec. 5, 2008 @ 23:02 GMT
May I hope for an expert answer, maybe by someone else?
I consider my suspicion serious and - if justified - rather important.
Eckard
F. Le Rouge wrote on Dec. 6, 2008 @ 11:27 GMT
No expert, please! (Experts are blind soldiers of Empiricism E. Blumschein, taking the differential for the common principle.)
I translated for you a quoting of R. Descartes, father of Empiricism as much as Newton, a quoting that proves that C. Rovelli or Lee Smolin are about three hundred and fifty years late if not more:
"First thing one have to be worried out is that many [Scientists] are mistaking Space idea with Time idea or Speed idea... If I would have link Speed idea with Space idea, I should have give necessarily three dimensions to Force, although I gave to Force only two dimensions to leave out Time.(...)" R. Descartes, September 12th 1638.
All the problems of today Physics are still included in this letter of Descartes who does not solve them but is rationally forgetting Time in Empiricism, that is to say Force, Energy, Inertia and ballistic problems. Rovelli says he is doing it like Descartes but he is keeping Time as a convention! Nothing is more subjective.
Notice E. Blumschein that Descartes is 'anticipating' A. Einstein or H. Bergson attempts to put Time again in Empiricism (probably for cultural reasons, love of poetry and music that are changing the subtle Time in something stronger).
The question of Time and the question of what does Planck say about Einstein and Einstein about Planck, those questions we are turning around and turning around since three hundred and fifty years are in Descartes quoting.
Even if it is difficult to fight against Empiricism or Algebraic Geometry because it gives the illusion of seriousness (3,14 looks more serious than 4 or 3), my opinion is that "experts are dead already". It is still like they are speaking from the Past.
Eckard Blumschein wrote on Dec. 6, 2008 @ 23:16 GMT
F. Le Rouge,
Even if we are at risk to forget Carlo Rovelli instead of forgetting time, your hint to Descartes reminds me of the fact that Descartes hesitated to introduce coordinates with
not just positive but also negative values. Admittedly I did not read it in the original but in a small booklet on Albert Einstein by Cornelius Lanczos (Loewy) which was translated in Russian language.
I also read somewhere that Fourier was pondering whether or not to integrate not from minus infinity to plus infinity but from zero to infinity.
Furthermore I read an argument of contemporary physicists: Restriction to past time would not be reasonable because prediction is the main goal of physics.
Hopefully you will understand my point of view from 369.
My question to Carlo Rovelli was how do we - step by step - arrive at the complex frequency domain when we start from a measurable, i.e., past function of time? Can complex frequency domain simultaneously include complex time domain?
Descartes did not have any chance but to make the first step by introducing the still ubiquitously accepted notion of Christian time which is also Christin's time. The void future "semigroup" is redundant. That's my message.
Could the consequences be like a purifying lightning? Hopefully I will still witness the failure of LHC to confirm the standard model. I guess, Nimtz will nonetheless continue to claim having proven superluminal propagation of signals.
Physicists are too proud as to take an old engineer serious.
Eckard Blumschein
Tevian Dray wrote on Dec. 8, 2008 @ 06:59 GMT
As a physical mathematician (the converse of a mathematical physicist), my view of mathematics often differs from my pure mathematician colleagues. Nowhere is this more noticeable than when I teach calculus, which, as traditionally taught, is about functions. But science is about equations, that is, about relations between physical quantities, not about dependent and independent variables.
Never in my wildest dreams did I imagine that all those related rates problems in fact contained a possible resolution to one of the universe's most vexing questions, namely what the nature of time is, or perhaps what it is not.
amrit wrote on Dec. 8, 2008 @ 14:11 GMT
Dr. Rovelli
yes, time is not a fundamental physical reality
time is an observer effect
yours amrit
attachments:
1_THE_THEORY_OF_ATEMPORALITY__SORLI_2008.pdf
Eckard Blumschein wrote on Dec. 9, 2008 @ 00:45 GMT
Tevian Dray,
Maybe, you didn't write an essay, maybe I overlooked it. My essay is nearly the opposite of what prefers the majority from Baez to Wheeler. The majority is strong enough. It does not need your support. Why do you deny the distinction between cause and effect in physics?
A key argument of mine is the limitation of original physical quantities to quantities that cannot change their sign.
I am calling it not an equation but an inequality if for instance pressure is always positive except when measured on log scale while sound pressure alternates around the dc component, and the elementary electric charge is negative. Likewise one can not measure negative distance and also not negative duration.
I asked Carlo Ravelli to explain step by step how the i in his equations 5, 19, 24, 26 can be derived from reality.
I was not surprised that he refused to do so because already Charles Francis in spf was also unable to do so.
While they could do it quite easily, they were forced to admit that some strangeness of quantum mechanics could be explained as consequence of improper interpretation of complex quantities.
Apparently they prefer taking quantum mechanics a gospel and deny the elapsed time instead. Carlo Ravelli even suggests to forget time in general. Mors certa, the clock is uncertain.
Eckard Blumschein
Yuri Rylov wrote on Dec. 9, 2008 @ 10:19 GMT
Dear prof. Rovelli,
I liked your radical approach to a description of physical phenomena. You suggest a timeless description. I believe, that your approach is insufficiently radical. In my opinion, one should use coordinateless description for the space-time geometry. Such a description is used in the Euclidean representation of the geometry, which is used for a teaching in the middle school.
However, the main problem of contemporary physics lies in the fact, that our knowledge of geometry is poor. We cannot describe discrete geometry. We cannot describe geometries with restricted divisibility. We know only axiomatizable geometries, which can be deduced from some system of axioms. However, the axiomatizable geometries form only negligible part of all possible geometries, which are mainly nonaxiomatizable. In particular, the true space-time geometry admits one to consider the principles of quantum mechanics as needless.
Let me explain the situation in a simple example. Let us imagine a person N, who does not know, that the quadratic equation has two roots. (He thinks, that the quadratic equation has only one root). I understand, that such a situation is rather unreal, but nevertheless, let us consider this situation. Constructing theories, the person N may meet such a situation, when one needs two roots of the quadratic equation. In this case he should think about his knowledge of algebra.
But the person N is self-opinionated. He invented new hypotheses, which admit him to compensate his poor knowledge of algebra. These new hypotheses are simple fittings, but in some cases these fittings work successfully. In other situations these fittings cease to work, and the person N is forced to search for other fittings.
Principles of quantum theory and, in particular, the quantum theory of gravity are such fittings, generated by our poor knowledge of geometry. There is a lot of papers on this subject (look in Aricheves, searching my name “rylov”. It is enough). There is also my essay on this contest.
My slogan is: “Find and correct mistakes! New ideas are needless!”
Sincerely yours,
Yuri Rylov
Adam Helfer wrote on Dec. 10, 2008 @ 23:35 GMT
Dear Carlo,
I've been reading your essay with interest. There are some points I'd like to understand. (Sorry about the long post -- that's what you get for writing a stimulating essay!)
(a) Am I right in thinking that you adopt the Schroedinger rather than the Heisenberg picture in order to try to pass to a theory of quantum gravity? (If we limit ourselves to, say, quantum fields in curved space-time, then the Heisenberg picture is more naturally relativistic, does not distinguish a particular time parameterization, and seems to meet most of your concerns -- although it does not explain the nature of time.)
(b) My main question is, What is the significance of thermal time? Your hypothesis is that this is "what we call 'time'" and "physical time." Since, however, as you emphasize, no relativistically invariant notion of "time" in general, it seems it must be some sort of cosmic time, or time somehow collectively generated by a system. Under what circumstances could we expect thermal time to approach one of our other notions of time?
Suppose I have a simple spin 1/2 system, which I prepare in a (constant) state
epsilon |up>
Adam Helfer wrote on Dec. 10, 2008 @ 23:39 GMT
[The following seems to have gotten cut off my last post.]
epsilon |up>
Adam Helfer wrote on Dec. 10, 2008 @ 23:44 GMT
[O.K.; the blog parser seems to be selecting against my states! Here goes again, with less technical notation.]
rho = epsilon (pure up) + (1-epsilon ) (pure down).
After preparation, the system does not evolve (it is insulated). What meaning, then, am I give to thermal time? It does not, with H_rho, generate evolution (the state remains constant). Does it connect with another, familiar, sense of time?
(c) Your program turns on the idea that the system considered is in a statistical state, which reflects "our ignorance of the microstate." How objective is the concept of "our ignorance of the microstate?"
I am guessing that you intend that there is at least a semi-objective way of quantifying this. Two possible approaches occur to me. One is some sort of coarse-graining (as in conventional thermodynamics). If that is what is intended, is it possible to give an idea of what this coarse-graining is?
The other possible approach to objectify knowledge of the microstate would be to consider the effects of quantum measurements as restricting the state. But those lead, not just to statistical restrictions, but to actual projections of a state vector (rather than a density matrix). (One could also consider some sort of mixed approach.)
One reason I am wondering about this is that the thermal Hamiltonian, being - log rho, would be very sensitive to the precise probabilities assigned to very unlikely states. Thus it seems that one has to spell out fairly precisely how to determine the statistical state in order for the thermal Hamiltonian to be well-defined.
Thanks,
Adam Helfer
F. Le Rouge wrote on Dec. 11, 2008 @ 18:25 GMT
To Blumschein:
-I will read your essay as soon as possible.
-Even if it is more serious from Descartes, father of the Algebraic Geometry to 'forget Time' when you say you want to forget it, although Rovelli is keeping it as nothing less than a dimension!?, nevertheless Descartes is trapped by the Potential Infinity postulate (see my forum) where Black Holes ideology is diverted. There is a Discontinuity in the Standard Model and where Descartes is speaking about 'slipping', Quanta Physics is speaking about 'black holes'.
mathtew kolasinski wrote on Dec. 12, 2008 @ 02:36 GMT
Hello Dr. Rovelli,
while i can fully appreciate an apparent confusion in identification of relationships in time with time itself and an interest in recognizing that what is referred to as time in physics is typically relative associations and wishing to do away with 't' in considering the relationships (essentially, i see no problems inherent in the math with conclusions 1 and 2), but,...
view entire post
Hello Dr. Rovelli,
while i can fully appreciate an apparent confusion in identification of relationships in time with time itself and an interest in recognizing that what is referred to as time in physics is typically relative associations and wishing to do away with 't' in considering the relationships (essentially, i see no problems inherent in the math with conclusions 1 and 2), but, relative as they may be, the relationships are not spatial in nature.
an example i used in a post elsewhere here:
we can toss a hula hoop out on a lake, put a little drop of oil in the center of the ring, monitor it's dispersion, note that it eventually fills the ring fairly evenly, watch the rainbows, have great fun 'till someone from the EPA shows up.
our calculations all include the expression "on the water".
we can set a couple of marker buoys on the lake and race a couple of boats around them, calculating their relative position to one another and the marker buoys all the while, and noting that, on the boats, they are always moving forward, regardless of which way they may turn.
our calculations all include the expression "on the water".
somewhere around the middle of the shoreline, wherever the middle of of a shoreline might be, we hop in an inner tube and go dog-paddling across the lake. it's a big lake. we paddle and paddle... count the number of strokes, intending in this way to measure how big the lake is... lose site of the shoreline... never find an end to the water... maybe somewhere in the wee hours of the morning we slip exhausted from the inner tube and disappear.
again, our calculations include the expression, "on the water".
our local situation may be compared to a bunch of people on a raft being towed around the lake by the sun, much as a water-skier might be towed.
some have gotten to looking at the calculations and wonder just what that "on the water" means in them; some ask if the calculations prove that water exists, others whether or no one can dispense with the idea of "on the water" in the equations and some get to questioning if there even is any water.
another example:
it is possible to define points of data on a hard drive in terms of relationships to one another. it is possible to run programs on the hard drive and describe then in more or less the equivalent of thermodynamic processes.
but it is not possible to have the data points without the hard drive.
the concept of time is somewhat a perceptual problem.
we have what is referred to as consciousness.
if we had just that, there would be no perception of time.
we might say that, with rotating consciousness through one dimension, we have memory.
this permits of an impression of 'duration' otherwise unavailable. it is only in that impression of 'duration' that a notion of 'time' arises at all.
yet it is only a vague sense of something there - akin to what a fish might have of water.
there is no way of parameterizing the perception - perceptually, there is no 'contrast' (required for perception) in that we cannot step outside of time. it would require another dimensional rotation of memory to be able to acquire an appropriate perspective and that is rather difficult to visualize.
concerns with such a modeling involving 'forgetting time'...
in part the psychological impact this may have, leading to a further disassociation with the natural world. i can see this happening quite easily with our growing absorption in entirely human activity and a dwindling identification with the world in which we actually live. the cultural stage is ripe for such a break as appears evidenced in the popularity of your paper. is this an inevitable result of the evolution of consciousness? no 'home'?...
and the attitude toward the world further disassociation with it would likely bring...
science's successes in augmented prowess has occasionally also been its disasters in a lack of wisdom involved in application. what is lost is frequently not possible to see until the 'disaster' aspect has evolved.
the unnaturalness of the thermodynamic interpretation - seemingly putting the cart before the horse.
if adopted, a potential for limiting consideration of possibilities by removing a contextual component capable of pointing to potential additional possibilities; something akin to how a loss of memory would result in no temporal perception. that time, gravity and space are actually not terribly well understood raises some concern in eliminating reference to one of them simply because it does not appear to have any specific effect in itself other than being a potential for data to exist.
a sense of time appears fundamental in living creatures. even the most basic of life forms.
http://discovermagazine.com/2009/jan/071 (slime mold have a sense of a length of time)
from cognitive science, that consciousness is clearly capable of accessing distant past, distant elsewhere present and distant future events information with considerable fidelity, there is a strong suggestion of a space-like dimensional character to time seemingly unaccountable for with a simple thermodynamic model.
to say that 'time flows' appears to be a slight misapprehension; that we flow in time would appear more precise.
while i am in full agreement with the majority of your observations and do not see any real reason why your proposed approach could not be employed effectively, i remain unclear about the extent of desirability of advantages this may afford beyond a sort of Swiss 'neat and tidy' and have some concerns about potential unintended disadvantages.
please forgive me if this all has already been addressed somewhere in the posts here. i've still got a lot of reading to do elsewhere here and it's not easy to keep up.
please forgive me also if i have misinterpreted your paper in any way. my own background is a little different from yours.
thank you,
matt kolasinski
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Dimi Chakalov wrote on Dec. 12, 2008 @ 03:58 GMT
Regarding my posting from Dec. 2, 2008 @ 08:21 GMT above: Let's recap on the facts.
As of today, Carlo Rovelli's essay "Forget time" got 6 Registered Votes, and 103 Public Votes.
Yet he hasn't made any effort to explain what may happen to 3-D space in case we choose to "forget time". I do hope he will do this until the contest ending date, January 1, 2009.
Please correct me if I got it wrong: In the canonical formalism of today's GR, the foliation of spacetime into 3-D spacelike hypersurfaces enables the distinction of two infinitesimally neighboured hypersurfaces, so if we "forget" about [delta]_t, we must "forget" about the whole 3-D spacelike hypersurface as well. It's a package -- see the drawing attached.
Carlo Rovelli has been manifestly silent on this fundamental issue.
He wrote (Oct. 24, 2008 @ 17:53 GMT): "... I think that in order to have a clear picture the easiest thing is to "forget space" and "forget time", and only to talk about relations between observable quantities."
And in his latest posting (Nov. 9, 2008 @ 10:42 GMT), he added even more confusing remarks: "... the probabilities of all the possible specific-measurement's outcomes predicted by the theory must sum up to one. Unitarity in *this* sense must of course be implemented by the timeless theory, and it is."
It is totally unclear why would the "observable quantities" care about each other's relational stance, nor what would be the driving force that implements the unitarity principle.
For if Nature chooses to "forget time", the "observable quantities" would need human consciousness to get their job done. Or maybe Carlo Rovelli should re-write his essay?
If he chooses the latter, there is a simple way to convince us that we should indeed "forget time": The very mechanism which shapes '3-D space' should be proven non-existent.
Carlo: If you believe can kill the Heraclitian Time, you should first kill the generation of 3-D space.
Please do not "forget" the event of contest ending, January 1, 2009.
Dimi Chakalov
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adm.jpg
Carlo Rovelli wrote on Dec. 12, 2008 @ 13:11 GMT
Many questons to reply to!
Let me start from the last one, by Dimi Chakalov. Dimi asks "what may happen to 3-D space in case we choose to forget time". And comments "I do hope he will do this until the contest ending date, January 1, 2009." Here I am.
I think that the fate of space is precisely the same as the one of time. I think we better forget both space and time, in order to...
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Many questons to reply to!
Let me start from the last one, by Dimi Chakalov. Dimi asks "what may happen to 3-D space in case we choose to forget time". And comments "I do hope he will do this until the contest ending date, January 1, 2009." Here I am.
I think that the fate of space is precisely the same as the one of time. I think we better forget both space and time, in order to understand better understand the structure of reality at the Planck scale. So; why all the fuss about time, and little abut space? Because the idea that space is not an entity is a very old and much discussed idea in the past, while the absence of time is much less so. In fact, when Newton based his theory on the existence of space, he did so *against* the prevalent thinkinf, from Aristotle to Descartes, which was to conside space not as an entity but only a relation between existing things. For Aristotle and for Descartes, the world is *not* a big space inside which matter moves (like for Newton and for the ancient atomists). Rather, it is just an ensemble of things that can happen to be in a relation of being "touching" one another. So, getting rid of space at the fundamental level is not very new. I think that what general relativity does is precisely so. It is the realization that the Newtonian "space" is nothing else that one of the physical fields that make up reality. Relality is not a space inside which things moves, but rather an ensemble of fields in interaction. So, my answer is that we must forget space and forget time. Forgettin space is easy; we have centuries of traditions that give us exemples about how to think the world without a fundamental space. Forgetting time is more difficult, and it is what we are discussing here.
Dimi writes "Carlo Rovelli has been manifestly silent on this fundamental issue." No, I am not, I have written often about that, including earlier in this discussion.
I do not understand the other points raised by Dimi. He says my statement about unitarity is confused, but dos not say what he finds confusing. The statement is simple and technical. The theory must give predictions, namely associate probabilities to alternative measuremenet outcomes. These probabilities should sum up to one. This, in my understanding is unitarity.
Dimi also writes: "For if Nature chooses to "forget time", the "observable quantities" would need human consciousness to get their job done." No! certainly not. I do not want to bring consciousness into these problems. The quantities that I call relational are not relationas because they are perceived by consciousness. They are relational because they pertain to two systems and not one. For instance, velocity is relational. An object has a velocity only "with respect" to another object. I walk on a train and I have a velocity of 1meter per second "with respect to the train". This does not mean that the train has a cosciousness to be aware of my velocity!
Adam Hefler asks: "Am I right in thinking that you adopt the Schroedinger rather than the Heisenberg picture in order to try to pass to a theory of quantum gravity? " No, it is the other way around. I adopt the Heisenberg picture, which remains well defined in the absence of a preferred time. I am told by friends who were there thatin his last publc lecture (in Sicily) Dirac had a single slide, with the Heisenberg equations dA/dt = i hbar[A,H] and the text "Heisenberg picture is the right one". These equations generalize to timeless quantum dynamics, as I have discussed in the essay.
Second question by Adam: "My main question is, What is the significance of thermal time? " Thanks for this question. I think that the origin of the problem with time is that many of the characteristic feautures of time (flowing, irreversibilty, and so on) seem totally absent from the picture of the world given by dynamics, especially when this includes relativistic gravity. The thermal time is an attempt to find the physical baisis for *these* additional features of time.
I loved the post by Tevian Dry, above (Dec 8). Nice, Tevian!
Thanks also to the kind post by Luigi Acerbi.
Petr Frish writes "I would like to make it stronger = a conjecture: Flowing of time a a property of the observer. Any decent observer of course has a memory. An object (complex particle with no memory) does not experience a flow of time. etc" I do not disagree. In fact, if thermodynamical time depends on the statistical description, hance on the coarse graining, to some extent it *it* observer dependent. By I would not know how to implemenet this concretely in physics.
Dimi Chakalov (already mentioned above), in an earlier post writes "It seems to me that Rovelli's recipe for quantum gravity is this: take Quantum Mechanics and General Relativity in their current formulation, with all their well-known problems, blend them into some new theory with "patrial observables", and hope that the problems of QM may be solved from GR, and the problems of GR may be solved from QM." Very good point. How could there be a change that this recipe works? The reason, I think, is because it has worked wonderfully in the past. When there was a problem between relativity of velocity and the Maxwell equations, many wanted to change one or the other. Einstein didn't do either. He kept both, and found that the two would work together, if we drom some other implicit common sense assumption (simultaneity). Dirac found antimatter by simply taking special relativity and quantum theory, and seeing where did they take if taken together. Newton took seriously Galilo's acelleration and Kepler ellipses... and so on. Very often physics advances by *taking seriously* theories that have proven empirically effective, and making an effort to merge then. Sometimes the merge requires new idea. One of the new ideas I advocate (with many others) is that to merge QM and GR we need to forget time. The result is that some say I am too radical; others, like Dimi in this post, say I am too conservative... I don't know what I am; I am just trying to find tentative solutions to the problems on the table ....
Thanks for the interesting comment, Cristi.
I apologize for the posts I am not answering to. I am tryng to catch up...
Carlo Rovelli
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Eckard Blumschein wrote on Dec. 12, 2008 @ 13:12 GMT
Dear all,
Since Carlo Rovelli has been "manifestly silent", I will take issue concerning some positions by Le Rouge and Yuri Rylov uttered here and comments on Carlo and others made elsewhere. Please goto http://fqxi.org/community/forum/topic/369
You are welcome,
Eckard Blumschein
Anonymous wrote on Dec. 12, 2008 @ 16:21 GMT
Hi Carlo:
You wrote (Dec. 12, 2008 @ 13:11 GMT): "The result is that some say I am too radical; others, like Dimi in this post, say I am too conservative... I don't know what I am; I am just trying to find tentative solutions to the problems on the table .... "
1. I never said that you are "too conservative". What I actually suggested (Dec. 12, 2008 @ 03:58 GMT) was this:
If you believe can kill the Heraclitean Time, you should first kill the generation of 3-D space.
2. We all are trying to find tentative solutions to the problems on the table, but I'm afraid your approach is logically inconsistent: you "derive" statements about time and space from a theory -- GR -- that cannot say anything about those same statements. Your whole essay is tantamount to speculating on the precise conditions "inside" a singularity, knowing very well that GR cannot be extended outside its applicable limits.
I also suggested you to consult Prof. Karel Kuchar. If he is busy, I can quote from his research papers.
As to your relational ontology, please check out the so-called
Buridan donkey paradox.
Dimi
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George Ellis wrote on Dec. 12, 2008 @ 20:27 GMT
Hi Carlo,
Your essay is of course beautifully written and argued. Thank you.
Now in this essay competition, there is an important split between a number of papers putting the view that time is an illusion/does not exist, yours being a prime example, and a number saying time is not an illusion/does indeed exist, mine being in the latter category. Recently I have been under some...
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Hi Carlo,
Your essay is of course beautifully written and argued. Thank you.
Now in this essay competition, there is an important split between a number of papers putting the view that time is an illusion/does not exist, yours being a prime example, and a number saying time is not an illusion/does indeed exist, mine being in the latter category. Recently I have been under some pressure from colleagues to explain how I could maintain my position in the face of your expert arguments. So I decided, a bit reluctantly, that I'd better point out where I disagree with your paper, else I will lose the argument by default.
I think there are four areas where we have different views.
First, on pages 2/3 of your paper, you state that there is no preferred time variable in GR. This is correct as regards spacelike surfaces that can represent constant time. But proper time along world lines is indeed a preferred time variable in GR. The fundamental difference from Newtonian theory is that the preferred time is defined along world lines, instead of by spacelike surfaces. Proper times along timelike worldlines is what is measured by clocks ticking (p.3). So you focus on problems with surfaces of constant time, I focus on the meaningful nature of proper time along world lines. To some degree this accounts for our differing positions on the nature of time.
Second, you focus on timeless evolution described by a Hamiltonian. I suggest firstly that physical evolution is described by a Hamiltonian in the way you propose only for some forms of matter content: there must for example be no dissipative processes happening, including no friction. Your `general structure of dynamical systems' does not, I think, describe simple realistic systems with friction, e.g. a pendulum with air resistance. Once the pendulum has stopped, you cannot follow it backwards and determine its previous motion. So I do not concur with the statement at the top of page 5: "It appears that all elementary physical systems can be described by Hamiltonian mechanics" (at least not by the time reversible dynamics you describe). Secondly, I suggest that in the quantum case, the Hamiltonian only describes part of the dynamics, the other part being handled by {the measurement process/collapse of the wave function/ decoherence}, however one conceives of and describes it [see Penrose, The Road to Reality, sections 21.8 and 22.1, 22.2, and Chapter 29, and Isham's book Lectures on Quantum Theory].
Thirdly, and related to the last point, your `timeless quantum mechanics' (Section 5) has no prescription for when projection (i.e. measurement) will take place [lines after equation (9)], and the Probability statement (7) has no prescription for when anything occurs. But that is the place where time and time irreversibility enters. This is Roger Penrose's key point, developed in The Road To Reality and The Emperor's New Mind. So I suggest that your formulation of QM is timeless because it is incomplete: your dynamical description does not include any way of determining when unitary development will be replaced by projection (in Penrose's terms, when unitary evolution U will be replaced by state vector reduction R).
Finally, the discussion of the recovery of time [section VI] parallels Penrose' discussion of coarse graining [The Road to Reality, pp 686-707]. But the Thermal Time Hypothesis [p. 8] only applies to statistical systems with many particles interacting [`these features are not mechanical , they only emerge at the thermodyamical level']. It does not seem to apply to single particles, or pairs of particles that collide, or planetary motion. I disagree with this hypothsis: I don't see that thermodynamics is needed to describe the motion of the Earth around the sun, for example. You say 'time is the expression of our ignorance of the full microstates." I do not agree; in my view [following Boltzmann, Oliver Penrose, and others] it is *entropy* that expresses that ignorance. The following equations [(19)-(26)] describe how the time variable works in some situations. That does not imply what the *origin* of time is; it merely shows how it works.
So that's how I see the differences betwen our views. I am sure I still have much to learn that may change my view.
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Chi Ming Hung wrote on Dec. 12, 2008 @ 20:39 GMT
Kudos to George for his accurate and succinct criticism of the timeless view from the quantum gravity camp - you really nailed the issues! Would love to hear what Carlo and others in the timeless camp have to say in response...
Saibal Mitra wrote on Dec. 12, 2008 @ 21:41 GMT
Professor Ellis wrote about Hamiltonian time evolution: "...there must for example be no dissipative processes happening, including no friction..."
but everyone knows that friction forces arise when we describe microscopic degrees of freedom with which the system is interacting with statistically.
About unitary time evolution, it is not necessary to postulate a collapse to account for any experiments. Unitary time evolution alone is enough, see .eg. here:
http://arxiv.org/abs/quant-ph/0204129
http://arxiv.org/a
bs/quant-ph/0205108
If such a thing as a real non-unitary collapse were to exist, then one sohuld be able to falsify the standard decoherence results based on unitary time evolution in experiments of closed systems.
Chi Ming Hung wrote on Dec. 12, 2008 @ 22:14 GMT
Saibal,
You wrote:
"it is not necessary to postulate a collapse to account for any experiments. Unitary time evolution alone is enough".
I think this is a common misconception about decoherence. Decoherence by itself does not give a complete solution of the measurement problem, since all components of the mixed state still exist in a global superposition. To account for how this superposition jumps into one of the components in the final step, one has to invoke non-standard interpretations like the many-worlds interpretation.
Thus unitary time evolution alone is NOT sufficient to explain non-unitary quantum collapse, contrary to popular belief.
Saibal Mitra wrote on Dec. 12, 2008 @ 23:58 GMT
Ok, but the MWI lets the global superposition be as it is, while other "collapse interpretations" need to appeal to new unknown physics that would explain exactly how the collapse happens.
If you assume that measurements leads to a real non-unitary collapse of a wavefunction, then the whole system observer plus measured system inside a hypothetical closed box would evolve in a non-unitary way even if not measured by an external observer outside this closed box.
Since an observer is nothing more than a many particle system, one should expect that closed systems will, in general, not evolve according to the Schrödinger equation. It could be that the deviations from unitary time evolution become large only if the system is large and then the interactions with the environment get large too, making it impossible to measure such an effect.
Now, the fact that only a few papers have appeared that attempt to explain such a non-unitary time evolution from fundamental physics, suggests to me that the people who work on fundamental physics do not take it seriously.
Adam Helfer wrote on Dec. 13, 2008 @ 03:28 GMT
I am going to break in here because I believe that this exchange between Saibal Mitra and Chi Ming Hung (stimulated by George Ellis) brings to a point some key issues:
(1) In practice people who do calculations in quantum theory rely essentially on projecting the wave vector -- call it collapse or not as you please;
(2) In any conventional interpretation of quantum theory it is only through measurement that we actually learn anything objective about the world (we can only predict probabilities without this);
(3) No conventional interpretation by itself tells us when measurements actually occur or are likely to occur (although various proposals supplementing interpretations have been made);
(4) Decoherence can explain correlations of measurements, but it cannot, by itself, explain the measurements;
(5) The desire to avoid taking up the physics of what precipitates measurement seems to come partly from the fact that it has been little studied, so people are somehow unsure if it is a real question, and partly from a view that if the entire world is really described by quantum theory, then where is there room for a classical measuring apparatus?
It seems clear that physicists should be able to give a physical criterion for when measurements occur, however. This criterion evidently cannot come from within a standard interpretation of quantum theory; it must be a new element. (That does not mean one needs a radically new interpretation; it does mean one needs to figure out what physics is going on.)
Dimi Chakalov wrote on Dec. 13, 2008 @ 13:01 GMT
Hi Carlo,
I am also going to break in here, because I believe George Ellis made a crucial remark.
George explained his understanding of your claim that there is no preferred time variable in GR (George Ellis, Dec. 12, 2008 @ 20:27 GMT):
"This is correct as regards spacelike surfaces that can represent constant time. But proper time along world lines is indeed a preferred time...
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Hi Carlo,
I am also going to break in here, because I believe George Ellis made a crucial remark.
George explained his understanding of your claim that there is no preferred time variable in GR (George Ellis, Dec. 12, 2008 @ 20:27 GMT):
"This is correct as regards spacelike surfaces that can represent constant time. But proper time along world lines is indeed a preferred time variable in GR. The fundamental difference from Newtonian theory is that the preferred time is defined along world lines, instead of by spacelike surfaces. Proper times along timelike worldlines is what is measured by clocks ticking (p.3). So you focus on problems with surfaces of constant time, I focus on the meaningful nature of proper time along world lines."
On the other hand, in your
arXiv:gr-qc/0604045v2, p. 4, you explained your understanding of 'no preferred time variable in GR' in the following fashion:
"In general relativity, when we describe the dynamics of the gravitational field (not to be confused with the dynamics of matter in a given gravitational field), there is no external time variable that can play the role of observable independent evolution variable. The field equations are written in terms of an evolution parameter, which is the time coordinate x^0, but this coordinate, does not correspond to anything directly observable. The proper time [tau] along spacetime trajectories cannot be used as an
independent variable either, as [tau] is a complicated non-local function of the gravitational field itself.
Therefore, properly speaking, GR does not admit a description as a system evolving in terms of an observable time variable.
...
"This weakening of the notion of time in classical GR is rarely emphasized: After all, in classical GR we may disregard the full dynamical structure of the theory and consider only individual solutions of its equations of motion. A single solution of the GR equations of motion determines “a spacetime”, where a notion of proper time is associated to each timelike worldline (notice the remark by George above - D.C.).
"But in the quantum context a single solution of the dynamical equation is like a single “trajectory” of a quantum particle: in quantum theory there are no physical individual trajectories: there are only transition probabilities between observable eigenvalues. Therefore in quantum gravity it is likely to be impossible to describe the world in terms of a spacetime, in the same sense in which the motion of a quantum electron cannot be described in terms of a single trajectory."
It seems to me that you and George are discussing 'apples and oranges': you are discussing the problem of time in classical GR, while he was (tacitly?) implying some yet-to-be discovered quantum gravity in which the "meaningful nature of proper time along world lines" (George Ellis, Dec. 12, 2008 @ 20:27 GMT) would be akin to "a single trajectory" (arXiv:gr-qc/0604045v2, p. 4).
May I ask you to sort out this issue with 'scrupulous intellectual honesty' (C. Rovelli, arXiv:gr-qc/0109034v2, p. 9).
Please also notice my criticism of your Essay, posted earlier ( Dec. 12, 2008 @ 03:58 GMT and Dec. 12, 2008 @ 16:21 GMT): the Heraclitian Time, which corresponds to the very *generation of 3-D space*, is absent in GR.
Again, if you really believe, with scrupulous intellectual honesty, that we should "forget" time, you have to demonstrate the emergence of 3-D space from some primitive (Borel?) set of abstract mathematical points, and then prove that this *emergence* is indeed timeless.
Please act promptly: the Heraclitean Time you have by the contest ending (January 1, 2009) is running out.
Dimi
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Peter Leifer wrote on Dec. 13, 2008 @ 15:51 GMT
Dear Carlo,
I've read in some of your replies that you are ready ``forget space-time". In SOME sense it is possible. Please see technical detailes in
http://www.fqxi.org/community/forum/topic/327.
Best regards,
Peter
Chris Kennedy wrote on Dec. 13, 2008 @ 19:11 GMT
Hi Carlo,
Great essay. I think you do a great job of providing a historical reference frame for this topic before you introduce your own ideas. Very enjoyable.
You argue that the origin of time variable features are not mechanical, rather – emergent at the thermodynamical level. Do you have any thoughts as to how velocity or gravity affect the time dilation of these thermodynamical activities? It seems to me that despite all of the essays, with so many different opinions of time’s true nature – we have only two possible fundamental starting points:
1) That the thermodynamical activity, or motion (or what I refer to as fundamental behaviors in my essay) is used as a measurement of “time” but plays a more passive role because these behaviors exist “in” time and their behaviors are just a visible symptom of what “time” they existed in due to their local environment.
Or
2) What we perceive as time is a macro effect of the most fundamental behaviors among particles, forces and fields. These behaviors define time and in fact are time. Now, if the most fundamental behaviors can all be accurately described as motion, then – okay. But if some behaviors on the quantum level no longer make sense to be described as motion, then it is safer to refer to the fundamental activities as “behaviors.”
For those who commit to the first possible starting point, they would not appear to be in conflict with special relativity – namely Galileo’s principle. The existence of time would be part of the metric that particles and forces exist “in.” There would exist Einstein’s inseparable connection between time and light signal velocity. There would be no “mechanism” - instead, the relative nature of time would just be a co effect of velocity and/or changing gravitational position. Time would exist as a mysterious entity (or co entity) and more questions would certainly need to be asked as to how we could get closer to determining its true nature.
For those who commit to the 2nd possible starting point (which is the one I am committed to) that motions or behaviors define time and in fact are time: Let’s take a system with all of its fundamental behaviors and increase its velocity. These behaviors slow down. If the behaviors themselves “are” time and then become altered as a consequence of their increased velocity- then we need to revisit special relativity. Something is happening on the physical level that we currently don’t have a description for.
Thank you,
CJ
Vesselin Petkov wrote on Dec. 13, 2008 @ 20:36 GMT
Dear Carlo,
While I tend to agree with George Ellis' objections to your view on how time might be recovered, I do not see how any notion of objective time flow can be saved (let me note that the notion "timeless universe" is misleading; I think it should be "timeflowless universe").
It has been already realized that the traditional view of time flow - as an evolution of a three-dimensional world - is in a direct contradiction even with special relativity (the notion of a three-dimensional world is based on the idea of absolute simultaneity). Then versions of the growing block universe introduced by C. D. Broad in the twenties started to emerge - Ellis, Christian (gr-qc/0610049), Sorkin (gr-qc/0703098). All these versions claim that they do not allow any form of a preferred structure. However, I do not see how this claim can be supported if it is explicitly assumed that the existence of physical bodies is absolute. Then it becomes evident that the growing block universe model also contradicts relativity - the hypersurface (no matter how complex its shape might be) on which the birthing of events happens constitutes an objectively privileged hypersurface (existence is absolute!) and therefore an objectively privileged reference frame. To avoid such an objection Christian proposed that existence should be relativized. To my knowledge, no one has succeeded in providing convincing arguments to defend such a notion.
I have failed to see the justification of what George Ellis wrote that the "time evolution is not related to any preferred surfaces in spacetime; rather it is associated with the evolution of proper time along families of world lines" and also (Fig. 2): "The particular surfaces have no fundamental meaning and are just there for convenience (we need coordinates to describe what is happening)". If existence is absolute, the birthing of events in spacetime does constitute a given hypersurface (again, no matter how complex it might be). Let me stress - I do not mean how we describe the evolving spacetime; the point is what actually happens (and then we can talk about a description) - how the whole network of worldlines grow along the proper time of each worldline (or a family of worldlines). One can also ask additional questions about such an evolving spacetime - e.g. light-like worldlines should also evolve (obviously not in terms of proper time).
Vesselin Petkov
Narendra nath wrote on Dec. 14, 2008 @ 07:08 GMT
As many people,that many ideas about such fundamental concepts as space and time. Prof Carlo has his and so also the others. To understand the significance of both space and time, let us work out Physics without consideration of these concepts. The reality will remain elusive until we explain the observed facts with alternate concepts. After all the humans evolved these concepts and they are capable of evolving alternate ones. However, there will not be any science without some sort of precepts that lead to some logical concepts. Only then one works out the detailed explanations using mathematical tools to represent the observed facts as also to predict some that still need to be proved experimentally. As measurements will always be limited in sensitivity and accuracy, we still remain bound by such limitations. Thanks to it , we will continue to persue science as a professional activity. However, let us all always remember that we need to continue to build a better human society through our scientific endevours. If we are unable to do so, science may also collapse with humanity. The latter has got a priority over science which is just a professional activity tied to human welfare and basic curiousity about the environment around. Foundational aspects of science are closely linked to human development in a positive direction. Sorry, if it seems like a 'sermon', as i can't claim any such authority!
Dimi Chakalov wrote on Dec. 14, 2008 @ 14:01 GMT
Addendum to my request for clarification, posted on Dec. 13, 2008 @ 13:01 GMT:
George wrote (George Ellis, Dec. 12, 2008 @ 20:27 GMT):
"But proper time along world lines is indeed a preferred time variable in GR."
May I ask you to clarify the exact meaning of your "preferred time variable in GR" by elaborating on the affine connection. Let me quote from
Wikipedia:
"... parallel transport along the curve preserves the tangent vector to the curve, so
nabla_{dotgamma} dotgamma= 0
at each point along the curve, where dotgamma is the derivative with respect to t."
George: Is your "preferred time variable in GR" keeping track on *each point along the curve*? If yes, what is the mechanism of this tracking?
Also, is dotgamma the derivative with respect to some gauge-dependent coordinate time, t, or is it with respect to the proper time [tau] along spacetime trajectories?
Regarding the latter, Carlo wrote (C. Rovelli, arXiv:gr-qc/0604045v2, p. 4):
"The proper time [tau] along spacetime trajectories cannot be used as an independent variable either, as [tau] is a complicated non-local function of the gravitational field itself. Therefore, properly speaking, GR does not admit a description as a system evolving in terms of an observable time variable."
I trust Carlo will elaborate on the (timeless?) affine connection as well.
As
Alan Rendall acknowledged:
"In elementary textbooks on general relativity we read that the Einstein equations imply that small bodies move on geodesics of the spacetime metric. It is very hard to make this into a mathematically precise statement which refers to actual solutions of the Einstein equations (and not just to some formal approximations)."
Perhaps Carlo Rovelli's suggestion to "forget" time and space is rooted on some 'formal approximations'. Recall Murphy's Law No. 15: Complex problems have simple, easy-to-understand wrong answers.
Dimi Chakalov
George Ellis wrote on Dec. 15, 2008 @ 05:16 GMT
Discussion of my paper should prefereably be over in my thread, not here, nevertheless as there are two postings over here ask for answers from me, I will answer them here.
Dimi Chakalov, you ask "is dotgamma the derivative with respect to some gauge-dependent coordinate time, t, or is it with respect to the proper time [tau] along spacetime trajectories?" It is with respect to proper time $tau$: which is the meaningful physical time along world lines, and is also the curve parameter for which the geodesic equation has a zero on the right hand side (which is how it relates to parallel transfer).
Vesselin Petkov, you state "It becomes evident that the growing block universe model also contradicts relativity - the hypersurface (no matter how complex its shape might be) on which the birthing of events happens constitutes an objectively privileged hypersurface (existence is absolute!) and therefore an objectively privileged reference frame." I tried to argue that one should think only in terms of evolution at space time events or along world lines, and not try to consider the relation of times along different world lines and so on spacelike surfaces. However if one insists on doing so and considers relevant spacelike hypersurfaces, then yes, an objectively privileged time frame exists. There is nothing new in this: every physically realistic solution of Einstein's equations has preferred space sections, being just another case of the broken symmetries that are so fundamental in present day theoretical physics (the underlying equations have higher symmetries than their solutions). The classic case is the Friedmann-Lemaitre cosmological solutions of general relativity: no one in their right minds uses any time coordinate other than the preferred time coordinate that is always used! (which is of course proper time measured along the fundamental world lines). Objectively privileged hypersurfaces do indeed exist in standard cosmology, and in all physically realistic solutions. And in the end, the real-world evidence that time does indeed flow is overwhelming (example: this posting was not posted till I posted it at a particular proper time along my world line); if this demands that preferred space sections exist, so be it, too bad for any theory that denies their existence in the face of this evidence. The quote from Omar Khayam in my essay refers.
Finally what about evolution along lightlike world lines? yes this can in principle take place; but in my paper I tried to indicate that while this is a possibility, in real situations such as cosmology, signficant effects almost always propagate along timelike world lines rather than null ones. The only physically significant case where influences along null curves are important are in relation to lasers; but they themselves are physical objects that move on timelike world lines.
Robert Sadykov wrote on Dec. 15, 2008 @ 05:59 GMT
Dear Carlo Rovelli,
Very interesting approach: there is no time - there is no problem. Remaining within the bounds of the special theory of relativity, we cannot refuse the relativity of simultaneity, which concerns to events at a quantum level also. In the general theory of relativity the time plays a key role, therefore the quantum theory of gravitation without time in principle cannot be constructed on the basis of the general relativity. However, hopeless situations do not meet. The quantum theory of gravitation can be constructed as the alternative theory of gravitation. One of many alternative approaches to time and gravitation is presented in essay
The Theory of Time, Space and Gravitation.
Regards,
Robert Sadykov
Lawrence B. Crowell wrote on Dec. 15, 2008 @ 13:33 GMT
I suppose I will throw in my 2 cents on this. I don't think that science can tell us about the existential status of geometric entities. If one considers a point x in spacetime, one can chose two different spatial surfaces S and S' where one pushes this point x to x' and x" which are not equal. General relativity is not about geometric entities, such as points, but it is about the relative motion of particles, such as the goedesic deveiation equation
x^a_{ss} = R^a_{bcd}U^bV^cU^c,
where x_{ss} = 2 derivatives with respect to proper time. So GR does not tell us about the existence of points, or as in the old perspectie "events," but it does tell us about intervals between them (proper time) and permits us to compute the dynamics of particles.
Quantum mechanics and general relativity involve two different notions of time. In quantum mechanics a Hamiltonian is defined by specifying a coordinate time. The Hamiltonian in a Neotherian perspective is the generator of time translations. Yet in general relativity this coordinate time is just a bookkeeping device we impose.
So we are caught with two different concepts of time in our two pillars of physics. There is a third pillar which is thermodynamics, and the so called arrow of time due to the second law of thermodynamics.
In #370 I suggest that time is a scaling principle. Imaginary time t = hbar/kT, for T = temperature in an AdS/CFT setting plays the role of a possible renormailization group. If we think of spacetime as composed of Sakharov oscillators (pregoemtry) the temperature T tells us how many of these modes are excited, which in turn can determine the scaling principle for the phase of spacetime.
I don't know if physics can ever tell us whether time exists or not, but it is an aspect of model systems that is useful.
Lawrence B. Crowell
Dimi Chakalov wrote on Dec. 15, 2008 @ 14:14 GMT
George,
Thank you for your partial reply from Dec. 15, 2008 @ 05:16 GMT.
Is your "preferred time variable in GR" identical to what you just dubbed 'the meaningful physical time $tau$ along world lines'?
Is the latter observable (=read by a physical clock), or is it "the explicit (but unmeasureable) time" suggested by Bill Unruh?
Can you solve the Cauchy problem for Einstein field equations with your "preferred time variable in GR" or 'the meaningful physical time $tau$ along world lines'?
What is your 'test of the pudding', actually?
Dimi
Alexander Silin wrote on Dec. 15, 2008 @ 17:34 GMT
Lawrence B. Crowell wrote " So we are caught with two different concepts of time in our two pillars of physics. There is a third pillar which is thermodynamics, and the so called arrow of time due to the second law of thermodynamics".
May be, GR operates with ensemble of particles only. On the one hand, the ensemble has statistics of interaction (i.e. it has thermodynamic time); on the other hand it has gravitational mass.
The QM examines wave function microparticle on a background of temperature time of this ensemble.
Dimi Chakalov wrote on Dec. 15, 2008 @ 20:05 GMT
On Dec. 12, 2008 @ 13:11 GMT, Carlo Rovelli wrote:
"I apologize for the posts I am not answering to. I am tryng to catch up..."
No rush, please take your time. I believe have showed that your approach is logically inconsistent -- please check out my postings above from Dec. 12, 2008 @ 16:21 GMT, Dec. 13, 2008 @ 13:01 GMT, and Dec. 14, 2008 @ 14:01 GMT, and follow the links.
In a nutshell, your logical error would be similar to the following claim: Fish cannot ride bicycles, therefore we should "forget" about bicycles.
More on the intrinsic limitations of GR in my posting to
Gavin Crooks from Dec. 13, 2008 @ 20:55 GMT.
Dimi Chakalov
Adam Helfer wrote on Dec. 15, 2008 @ 20:45 GMT
Dear Carlo,
Thanks for clarifying your use of the Heisenberg representation. (I now see I had too quickly jumped to a misinterpretation of some of your notation.)
I also appreciate your comments that thermal time is meant to get at concepts of flow and irreversibility. If it is possible to be more precise (for example, to say how thermal time is measured, or to what systems the concept of thermal time applies), that would be helpful.
In this connection (trying to understand just what thermal time was) I raised some other questions (about the objectivity of the concept, and about its application to simple systems) in my previous post, and if you get a chance I'd be interested in the answers.
Thanks,
Adam
Vesselin Petkov wrote on Dec. 16, 2008 @ 02:58 GMT
What does "the real-world evidence" support - an objective flow of time or the block universe view?
As what George Ellis wrote above "the real-world evidence that time does indeed flow is overwhelming" is quite relevant to the topic of this contest and especially to Carlo Rovelli's position I will comment here. But my comments on his statement "Objectively privileged hypersurfaces do indeed...
view entire post
What does "the real-world evidence" support - an objective flow of time or the block universe view?
As what George Ellis wrote above "the real-world evidence that time does indeed flow is overwhelming" is quite relevant to the topic of this contest and especially to Carlo Rovelli's position I will comment here. But my comments on his statement "Objectively privileged hypersurfaces do indeed exist in standard cosmology, and in all physically realistic solutions" will be posted on his thread. Lawrence Crowell's "I don't think that science can tell us about the existential status of geometric entities" will be addressed on my thread.
Yes, of course, the evidence that time flows is indeed overwhelming, but that evidence is not physical. If the evidence is analyzed rigorously it becomes clear that it boils down to the fact that we realize ourselves and the world at the constantly changing moment 'now'. But it does not necessarily follow from that undeniable fact that the world itself also exists only at (or up to) the present moment. That is why Hermann Weyl, who certainly was aware of "the real-world evidence", conjectured that it was our consciousness crawling along the worldtube of our body that creates that evidence and the feeling (illusion) that time flows. I would suggest that all who disagree with the block universe view analyze only Weyl's conjecture and try to find just one example (or even a hint of an example) when it fails to explain what we perceive as flow of time.
To avoid any misunderstanding, George Ellis' "The time reversible picture of fundamental physics underlying the block universe viewpoint" (p. 3 of his essay) is not quite correct. The block universe view does not follow from the reversibility issue; that issue was known before Minkowski introduced the concept of spacetime. It is the spacetime idea that underlies the block universe view - if spacetime is not just an abstract mathematical space but represents a real four-dimensional world, we call that world a block universe.
Also incorrect, in my view, is another statement: "This irreversibility is a key aspect of the flow of time" (p. 1 of his essay). I think the majority of relativists will agree that the irreversibility of physical processes demonstrates the anisotropy of spacetime and does not imply an objective flow of time. Let me specifically stress - we are not asking how to describe spacetime in terms of the idea of time flow (based on our three-dimensional language); we ask the fundamental question - is the future as real as the past, or more precisely, is the world four-dimensional (a block universe)?
The real situation is, in fact, opposite to what George Ellis wrote -- the macro scale evidence supporting the block universe view is overwhelming. Consider even special relativity and ask whether the experiments (not just the theoretical results), which confirmed its kinematical predictions (relativity of simultaneity, length contraction, time dilation, twin paradox), would be possible if the physical objects involved in these experiments were three-dimensional or growing four-dimensional worldtubes.
Here is a very quick example of such an analysis in the case of length contraction. First, take into account that an extended three-dimensional body is defined in terms of simultaneity - all its parts taken simultaneously at a given moment of time. Then, as length contractions turns out to be a specific manifestation of relativity of simultaneity, while measuring the same rod two observers A and B in relative motion measure two different three-dimensional rods (two different sets of the rod's parts) since A and B have different classes of simultaneous events. Is this would be possible if the rod were a three-dimensional object? Is this would be possible if the rod were a growing worldtube (see the attached diagram)?
In the case of the growing worldtube one might argue that we will always see only the completed part of the worldtube since we always see past events. That is, of course, correct but try to imagine how many tough questions the growing or evolving block universe has to answer (even tougher than the questions the block universe view itself has to answer) - (i) we are interested not only in what we observe (from what we observe we try to understand the world itself), (ii) how to explain, for example, the EPR-Bell-Aspect type of experiments, (iii) how to explain the inescapable conclusion that the evolving block universe is as predetermined as the block universe since the growing block universe will be merely actualizing the forever given events of the block universe (take into account the EPR-Bell-Aspect type of experiments, for example, to see why), etc.
And one last point - the probabilistic behaviour of quantum objects does not necessarily contradict the forever given spacetime picture of the world. To see why this is so, assume that the quantum objects do not exist continuously in time (which means that they would have an internal frequency).
Vesselin Petkov
view post as summary
attachments:
Growing_4D_World.pdf
Vesselin Petkov wrote on Dec. 16, 2008 @ 03:14 GMT
Correction
I am sorry for this correction (the error was caused by editing at the last moment). The last two sentences of the third paragraph from the bottom should read:
Would this be possible if the rod were a three-dimensional object? Would this be possible if the rod were a growing worldtube (see the attached diagram)?
Vesselin Petkov
George Ellis wrote on Dec. 16, 2008 @ 12:01 GMT
Dear Vesselin Petkov,
Thank you for the most interesting and thoughtful challenge to the Evolving Block Universe idea that I have yet received. With apologies to Carlo I will answer it on this thread, as you have posted your challenge here.
First you state, “If the evidence is analyzed rigorously it becomes clear that it boils down to the fact that we realize ourselves and the...
view entire post
Dear Vesselin Petkov,
Thank you for the most interesting and thoughtful challenge to the Evolving Block Universe idea that I have yet received. With apologies to Carlo I will answer it on this thread, as you have posted your challenge here.
First you state, “If the evidence is analyzed rigorously it becomes clear that it boils down to the fact that we realize ourselves and the world at the constantly changing moment 'now'. But it does not necessarily follow from that undeniable fact that the world itself also exists only at (or up to) the present moment. That is why Hermann Weyl, who certainly was aware of "the real-world evidence", conjectured that it was our consciousness crawling along the worldtube of our body that creates that evidence and the feeling (illusion) that time flows.” The problem with this view is fundamental: how can our consciousness manage this astonishing feat, if we really inhabit an unchanging block spacetime and the flow of time is an illusion? The point is that our mind functions through the brain, a physical affair governed by the laws of physics that in some as yet understood way underlies our conscious perceptions. If time does not effectively flow *in our brain*, enabling the physical states of our neurons to succeed each other in timelike succession in a suitable causally patterned way, there is no way that consciousness can progress from one state to another. Modern neuroscience insists our brain is a physically based system, subject to the usual laws of physics; if they do not sensibly comprehend the flow of time, neither can our brain.
Second, you state “I think the majority of relativists will agree that the irreversibility of physical processes demonstrates the anisotropy of spacetime and does not imply an objective flow of time. Let me specifically stress - we are not asking how to describe spacetime in terms of the idea of time flow (based on our three-dimensional language); we ask the fundamental question - is the future as real as the past, or more precisely, is the world four-dimensional (a block universe)?”
I have tried to emphasize in my essay not just the irreversibility of time, but the fact that standard quantum theory implies that the future is not determined *even in principle* until it happens, although we do have probability predictions as to what will happen. The fundamental irreversibility of the quantum measurement process (you don’t even have a prediction of probabilities in the backwards direction of time) is a key aspect of what is going on.
Third you state, “the macro scale evidence supporting the block universe view is overwhelming. Consider even special relativity and ask whether the experiments (not just the theoretical results), which confirmed its kinematical predictions (relativity of simultaneity, length contraction, time dilation, twin paradox), would be possible if the physical objects involved in these experiments were three-dimensional or growing four-dimensional worldtubes.”, and you continue with the specific example of length contraction: “would [this] be possible if the rod were a growing worldtube?”
Yes it would. The key aspect of all these special relativity examples is the radar definition of simultaneity, so that is what I will concentrate on; all the rest will follow from this (for detailed discussion and spacetime diagrams, see my book “Flat and Curved Spacetimes” with Ruth Williams). So please consider an observer O moving on a worldline L relative to an arbitrary chosen Minkowskian reference frame in flat spacetime. She emits a photon at event E1 on her world line, it is reflected by a distant object M at an event R on its world line, and received back by O at the event E2 on her world line, after a proper time T has elapsed since E1. She then determines that the event P on her world line is simultaneous with R, where the proper time along her world from E1 to P is T/2, which is also the proper time along her world line from P to E2. Thus she in principle determines all spacetime events simultaneous with the event P in her history.
Now the key point is that she notionally determines what other events are is simultaneous with P, after the event: E2 occurs after P. An evolving block view is completely compatible with this, because there is no requirement that the spacelike surfaces of time on which coming-into being takes place be surfaces of simultaneity for the observer O. Her surfaces of constant time are all determined by her measurements in the past, after the events that are determined to be simultaneous have come into being. The photon traveled along the path it traversed as the block universe unfolded, arrived back at her world line at event E2, and then allowed her to determine that the past event P was simultaneous with R. Similar analysis will apply to length contraction and all other special relativity measurements: there is no problem for the EBU.
I will not attempt to respond here concerning the EPR-Bell-Aspect type of experiments; I am reasonably sure that whatever works to make it compatible with special relativity in the usual Block Universe will also work for the EBU. I do not understand your comment “how to explain the inescapable conclusion that the evolving block universe is as predetermined as the block universe since the growing block universe will be merely actualizing the forever given events of the block universe (take into account the EPR-Bell-Aspect type of experiments, for example, to see why).” If you are claiming that the outcome of quantum measurements is predetermined before they have happened, then you are contradicting the standard views of quantum theory: please refer for example to the writings of Richard Feynmann and Chris Isham. You seem to have forgotten the foundational two slit experiments.
Finally you state “the probabilistic behaviour of quantum objects does not necessarily contradict the forever given spacetime picture of the world. To see why this is so, assume that the quantum objects do not exist continuously in time (which means that they would have an internal frequency).” Please enlighten me as to how this leads to the definite prediction of the outcomes of *all* quantum experiments, not just the EPR type experiments, and hence to a definite spacetime outcome.
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Lawrence B. Crowell wrote on Dec. 16, 2008 @ 14:20 GMT
Vesselin Petkov:
Thanks for your comments. Time and space are what I call relationship structures. They are geometric entities which tie kinematic entities to dynamical ones. As such I tend to suspect that science is unable to tell us in much on whether these actually exist. For that matter the term exist or existence is a bit of strange, and ontological categories appear to have a measure of "relativity" to them.
Fotini has an interesting paper which appears to be getting less attention on how time exists and space does not. I have yet to comment on this paper, mainly because I need to come up with something substantial, but it is curious that one would choose to say time exists but space does not --- an apparent complementary view to Rovelli's. To be honest I wonder if the apparent Carlo-Fotini dualism here suggests something.
The evolving block world might be captured within my Escher disk perspective on AdS. Each tessellation of the AdS is a particular tiling of the spacetime. How each "cell" joins other cells is a way in which a quantum path might split. So a particle which leaves the BTZ black hole horizon the AdS contains, or leaves the boundary at v ~ c will follow an arc or path, but there are at each vertex a set of crossing paths. These are other amplitudes, which in a decoherence or measurement etc may push the particle onto. So in that setting the "block" is the set of all possible paths, but the "evolute" is the particular path a particle may take as it approaches the boundary with v ---> 0.
Lawrence B. Crowell
Dimi Chakalov wrote on Dec. 16, 2008 @ 15:56 GMT
[My apologies to Carlo for breaking into his thread]
On Dec. 16, 2008 @ 02:58 GMT, Vesselin Petkov wrote:
"Yes, of course, the evidence that time flows is indeed overwhelming, but that evidence is not physical."
If the evidence were physical, there would be some bona fide (Dirac) observable in GR, which would reveal the source and the origin of the "dynamic dark energy", and the ether will come back.
Therefore, we should not expect to catch any *physical* evidence for the flow of time.
You also wrote (ibid.): "... the macro scale evidence supporting the block universe view is overwhelming."
Please see a startling confession by Thomas Thiemann in astro-ph/0607380 v1:
"The puzzle here is that these observed quantities are mathematically described by functions on the phase space which do not Poisson commute with the constraints! Hence they are not gauge invariant and therefore should not be observable in obvious contradiction to reality."
More in my post to
Gavin Crooks from Dec. 13, 2008 @ 20:55 GMT.
Dimi Chakalov
T H Ray wrote on Dec. 16, 2008 @ 16:04 GMT
Lawrence B. Crowell wrote,
"Fotini (Markopoulo) has an interesting paper which appears to be getting less attention on how time exists and space does not. I have yet to comment on this paper, mainly because I need to come up with something substantial, but it is curious that one would choose to say time exists but space does not --- an apparent complementary view to Rovelli's. To be honest I wonder if the apparent Carlo-Fotini dualism here suggests something."
I am curious about that myself, because way back in this thread I commented on that apparent duality coming from the Perimeter Institute, based on Carlo's previous papers on partial and complete observables. I wrote:
"...there may exist theories of complete observables and theories of partial observables that are dual to each other. That is, where a mathematically complete prediction corresponds to the partial observable event probability 1.0. I think that, consistent with Smolin’s theme of 'the present moment in quantum cosmology,' it is the principle of least action that preserves the present moment ..."
I never got a reply, and maybe it isn't worth one. However, I remain curious.
Tom
Lawrence B. Crowell wrote on Dec. 16, 2008 @ 17:23 GMT
I will try to read Markopoulo's paper again this week. It takes a bit to pick through the list of them here. As I have said there are two different views of time in GR and QM. GR considers the interval as the relevant defintion of time, while QM requires the use of the coordinate time to define wave equations. Of course it might be argued this is an artifact of our representation of quantum states in spacetime more than anything fundamental to QM. On my little #370 space I argue how on a GR frame that proper interval must be measured by some oscillating system which executes some small non-geodesic motion, possibly requiring the use of a coordinate time.
The dualism between our two concepts of time, GR v. QM, might manifest itself under some categorical or functorial map as a matter of either time or space disappears.
Lawrence B. Crowell
Chi Ming Hung wrote on Dec. 16, 2008 @ 21:57 GMT
Just want to add my 2 cents to the debate between the Block Universe (BU) and the Evolving Universe (EU) viewpoints.
It should be quite obvious that the BU viewpoint is indefensible once quantum phenomena are taken into account. More specifically, the objectivity of indeterministic and probabilistic transitions in quantum mechanics is completely at odds with a BU viewpoint (as pointed out by George Ellis).
On the other hand a EU viewpoint is not at odds with special relativity (SR), because all that's required is that the space-time events, after they've become determinate (through quantum measurement), obey the kinematics of SR, at least in the macro scale. Thus, contrary to popular misconception (e.g. claims by Vesselin Petkov above), SR does not demand the existence of 4-dimensional objects, it only demands that the space-time events which constitute macroscopic objects (like rods and clocks) should obey the kinematics of SR, SR has nothing to say about whether these space-time events are part of a 4-D object, or an evolving 3-D object, or something else entirely.
It is perhaps understandable why Einstein and other classical theorists who denied the reality of quantum phenomena should accept the BU viewpoint, but it's rather inconceivable to me why any theoretical physicist today can still subscribe to the BU viewpoint...
Vesselin Petkov wrote on Dec. 17, 2008 @ 00:30 GMT
1. My comments on George Ellis' post above will be posted on his thread later today (Montreal time).
2. On Chi Ming Hung's label placing. I believe we all have been enjoying the generally constructive discussions on this forum. Unfortunately, your latest post cannot be regarded as constructive. I would suggest that before criticizing (in your post it is worse - placing labels) a view try to...
view entire post
1. My comments on George Ellis' post above will be posted on his thread later today (Montreal time).
2. On Chi Ming Hung's label placing. I believe we all have been enjoying the generally constructive discussions on this forum. Unfortunately, your latest post cannot be regarded as constructive. I would suggest that before criticizing (in your post it is worse - placing labels) a view try to do the obvious - make sure that you understand it first.
2.1. You stated: "Thus, contrary to popular misconception (e.g. claims by Vesselin Petkov above), SR does not demand the existence of 4-dimensional objects". I provided arguments; that you ignored them does not transform them into claims. I am afraid it is your position that reflects popular misconception. Here is the argument (not a claim) why I think so - sometimes people are making claims like yours because they do not bother to analyze in depth the relativistic effects (not even the special relativistic effects); try to do it now by answering the questions about length contraction I asked (and also check my post on George Ellis' thread). The length contraction and relativity of simultaneity arguments are given in more detail in Sec. 2 of my essay; even deeper analyses of them and also of time dilation and the twin paradox are given in Ch. 5 of my book "Relativity and the Nature of Spacetime" (Springer, 2005). It is shown there that these relativistic effects, and more importantly the experiments that confirmed them, would be impossible if the physical objects involved in those experiments were three-dimensional; in my previous post I attached a diagram demonstrating that the length contraction of a rod would be also impossible if the rod were a growing worldtube (and also briefly addressed a possible objection). Analyzing the relativistic effects by explicitly asking what the *dimensionality* of the physical objects involved in them is you will be in a better position to comment on whether or not special relativity demands "the existence of 4-dimensional objects".
2.2. You also stated: "It should be quite obvious that the BU viewpoint is indefensible once quantum phenomena are taken into account. More specifically, the objectivity of indeterministic and probabilistic transitions in quantum mechanics is completely at odds with a BU viewpoint (as pointed out by George Ellis)." Frankly, it is beyond my comprehension how you could write this.
First, you ignored not only the arguments demonstrating that relativity would be impossible if the physical objects were three-dimensional; you also ignored what I specifically wrote (to help those who post not to repeat the common misconception that quantum mechanics is incompatible with the spacetime picture of the world): "the probabilistic behaviour of quantum objects does not necessarily contradict the forever given spacetime picture of the world." I did not elaborate in order not to make the post too long. What I meant is briefly explained in Sec. 5 of my essay; the reference to the developed idea is also given there.
Second, how do you know "that the BU viewpoint is indefensible once quantum phenomena are taken into account"? Like anyone else you have no idea what is really going on in the quantum world. You wrote "the objectivity of indeterministic and probabilistic transitions in quantum mechanics" with which I completely agree, but believe that the block universe view is the correct view that is compatible with both relativity and quantum mechanics. Have you asked yourself "indeterministic and probabilistic transitions" of *what* we are talking about? Ultimately, we mean processes involving *quantum objects*. But we do not know what the quantum object is (just do not tell me we can't ask such a question). Only when we have the answer to that question we will know whether that answer will contradict or support the block universe view. For now, you have an example in my essay that demonstrates both (i) that the probabilistic behaviour of quantum objects does not necessarily contradict the forever given spacetime picture of the world, and (ii) that one can envisage a paradox-free quantum mechanics; these are possible when an implicit assumption - that the quantum object exists continuously in time - is identified and abandoned.
In these difficult times in fundamental physics, instead of being quick at placing labels, it will be much more helpful to try to understand one another to the best of our abilities. This is one of the necessary conditions for achieving the next breakthrough in physics.
Vesselin Petkov
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Chi Ming Hung wrote on Dec. 17, 2008 @ 03:03 GMT
Vesselin,
I wasn't "label-placing", merely stating what I think is a misconception, and I wasn't trying to offend anybody, sorry if you took it that way...
And no I didn't ignore your arguments, but I thought I already answered them in my comments... Perhaps I need to elaborate more on what I meant.
Your arguments about length contraction and relativity of simultaneity are classical special relativistic arguments, and based on just that, your conclusion about a block universe (BU) viewpoint is not subject to controversy, but they don't take into account quantum phenomena.
Specifically, rods and clocks are nothing but correlated collections of space-time events. You're correct that nobody knows exactly what goes on in the quantum world which gives rise to these correlated collections of space-time events we call rods and clocks. But it's safe to assume that whatever is going on, we should end up with correlated collections of space-time events which look and behave like rods and clocks in special relativity (SR), because otherwise we can't have faith in either SR or quantum mechanics (QM).
But can we infer from this that rods and clocks are 4-D objects? No I don't think we can, or at least it doesn't serve any useful purpose to do so. The reason I said SR has nothing to say about this matter is because the end results would be the same: there are no 4-D or 3-D objects, only correlated collections of space-time events.
It's true that my arguments are of the hand-waving sort, but until we have a better theory of the transition from quantum to classical phenomena, that's the best we can do for now.
On the other hand, your arguments about length contraction and relativity of simultaneity are also of the hand-waving type because they didn't take into account the quantum nature of rods and clocks.
As for the objectivity of indeterministic and probabilistic transitions in quantum mechanics, the evidence should be abundant: radioactive decay, single-photon double-slit experiment, Stern-Gerlach experiment etc. etc. Yes there have been attempts to explain these as outcomes of deterministic theories (like Bohm's) but only at the cost of introducing yet more hidden unobservable stuff (like pilot waves), so in this case I invoke Occam's razor and just take the evidence at face value...
P.S. While I haven't read your essay in detail, I've read the section "Worldlines and Quanta", and believe it or not, some of your ideas resonate with those of mine, though I don't think they prove the compatibility of BU with QM... But I guess I should comment more about this (and your other arguments like that of the EPR-type experiemnts) later on your essay's forum, not here... In fact I think we should continue this discussion (if you like) in your essay's forum, because it's getting off-topic here...
Vesselin Petkov wrote on Dec. 17, 2008 @ 06:14 GMT
Chi (or Chi Ming please correct me),
I also think this discussion should continue on my essay's webpage. Here I will briefly comment just on:
"Your arguments about length contraction and relativity of simultaneity are classical special relativistic arguments, and based on just that, your conclusion about a block universe (BU) viewpoint is not subject to controversy, but they don't take into account quantum phenomena."
This is precisely what I mean. Quantum mechanics tells us nothing about the relativistic effects; these are macro scale effects confirmed by experiment. And as Minkowski anticipated these effects and experiments are manifestations of the four-dimensionality of the macro world.
Now, the interesting question is whether the quantum world is a block universe. I think it is, but in order to have a definite answer we need the answer of another question - what is the quantum object?
Vesselin Petkov
Robert Sadykov wrote on Dec. 17, 2008 @ 10:16 GMT
Dear Carlo Rovelli,
On a way to creation of the quantum theory of gravitation except for time other obstacles can meet. For example, a zero energy density of the gravitational field, as it is presented in an essay
The Theory of Time, Space and Gravitation. Gravitational quanta with zero energy will be very strange. Before creation of the quantum theory of gravitation or before creation of the theory of everything the fuller research of properties of the gravitation is necessary.
Yours faithfully
Robert Sadykov
amrit wrote on Dec. 17, 2008 @ 15:41 GMT
Dear Dr. Rovelli
You say: In short, I propose to interpret mechanics as a theory of relations between variables, rather than the theory of the evolution of variables in time.
I would say: Relations between variables run into atemporal space. We describe them in time as a mind model.
yours amrit
attachments:
1_Phenomenology_of_Time_and_Quantum_Gravity.pdf
Dimi Chakalov wrote on Dec. 18, 2008 @ 11:22 GMT
Vesselin Petkov wrote on Dec. 17, 2008 @ 06:14 GMT
"Now, the interesting question is whether the quantum world is a block universe. I think it is, but in order to have a definite answer we need the answer of another question - what is the quantum object?"
Regarding this "interesting question", please notice my posting from Dec. 15, 2008 @ 20:05 GMT, about fish and bicycles.
As to "what is the quantum object?", please check out the fist posting at
George Ellis' thread, from Dec. 2, 2008 @ 07:02 GMT, and my latest posting there, from Dec. 18, 2008 @ 10:59 GMT. It's all about an _arrow of spacetime_ . We should not separate time from space -- recall Hermann Minkowski.
Dimi Chakalov
Dr. E (The Real McCoy) wrote on Dec. 20, 2008 @ 22:27 GMT
Hello Carlo,
Hope all is well!
In this BBC video, Lee Smolin states, "Einstein taught us that space is not a background that things move in. Spoace is a network of relationships that are ever dynamical, ever evolving, part of the world. The geometry of space evolves and changes--WIGGLES--just like anything else==just like electromegnetism, just like...
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Hello Carlo,
Hope all is well!
In this BBC video, Lee Smolin states, "Einstein taught us that space is not a background that things move in. Spoace is a network of relationships that are ever dynamical, ever evolving, part of the world. The geometry of space evolves and changes--WIGGLES--just like anything else==just like electromegnetism, just like particles."
http://www.youtube.com/watch?v=3bLwqnIfLRA&featur
e=related
So it is that dimensions move.
All that my theory--Moving Dimensions Theory--does is note that the fourth dimension is expanding relative to the three spatial dimensions, as attested to the photon which is ageless in relativity and nonlocal in quantum mechanics.
From MDT's simple postulate and equation dx4/dt=ic, all of relativity is derived.
Give me a universe wherein we have four dimensions x1, x2, x3, x4 and the fourth dimension is expanding relative to the three spatial dimensions, or dx4/dt=ic, and all of relativity arises.
This is a simple, buautiful postulate and principle--indeed, Einstein's principle of relativity descends form MDT's postulate. And MDT is more succinct than relativity, for from MDT's single postulate and equation comes both of relativity's postulate.
Also from MDT's simple postulate and equation comes a natural *physical* model for time and all its arrows and assymetries, as well as entropy, quantum nonlocality and entanglement, all the dualities--space/time, mass/energy, wave/particle--and both Heisenbergs' and Huygens' principles.
dx4/dt=ic (underlying relativity) suggests that the fourth dimension is expandingh at c.
xp-px = ih (underlying quantum mechanics) suggests that the wavelength of this expansion is Planck's length.
So it is that MDT sets both Planck's constant and the veloicty of light, while also maintaining the ocnstancy of the velocity of light by giving rise to all of relativity.
Lee Smolin also states in the video, "We've forgotten how audacious science is and how it rages sometime -- how the ideas that turn out to be true are so often outrageous... we've forgotten the lessons of the people like Einstein, who come from the outside but have exactly the right insight and right idea." --http://www.youtube.com/watch?v=3bLwqnIfLRA&feature=related
BBC Hard Talk
"Openness, the inclusion of different points of view, like in anything else, is essential to progress." --Lee Smolin http://www.youtube.com/watch?v=3bLwqnIfLRA&feature=related BBC Hard Talk
In light of all this, I was hoping for some more dialogue; as there is nothing to lose by discussing foundational questions in a collegial, professional manner, and everything to lose by silence and solitude.
Too, too many established professors and researchers refuse to partake in dialogue, and this grates against the spirit of greats such as Wheeler, Einstein, and Galileo.
"I have never met a man so ignorant that I couldn't learn something from him." --Galileo Galilei
"Curiosity is more important than knowledge." --Einstein
Lee Smolin also says that a theory should "come in a coherent whole--it should start with a beautiful principle, like the principle of indeterminacy of quantum mechanics or the principle of relativity, and there then should be a beautiful equation that flows out form that principle to a myriad of consequnces." --Lee Smolin
MDT's beautiful principle: The fourth dimension is expanding relative to the three spatial dimensions at c with a wavelength of the Planck Length.
MDT's beautiful equation: dx4/dt=ic
MDT's myriad of consequences: all of relativity, time and all its arrows and assymetries, entropy, quantum nonlocality and entanglement, wave-particle/space-time/mass-energy duality, the gravitational slowing of light and time, and the single velocity for all entities through spacetime--c.
Well, Carlos, your silence on MDT after having promised to read the paper has lead me to believe that you see nothing wrong with MDT, as unlike LQG and Sring Theory, it passes Dr. Smolin's criterion for a good theory. And too, MDT predicts all of relativity along with quantum nonlocality and entanglement, as well as entropy, by proposing a novel, deeper feature of our *physical* reality.
Best Wishes!
Soon these comments will be frozen for all time, while the fourth dimension yet marches on at the rate of c!
I look forward to sending you a copy of my book, HERO'S JOURNEY PHYSICS & MOVING DIMENSIONS THEORY: FROM HERACLITIS, TO PLATO, TO ARISTOTLE, TO COPERNICUS, TO BRUNO, TO KEPLER, TO GALILEO, TO NEWTON, TO PLANCK/EINSTEIN/BOHR/BORN--AND YET IT MOVES! Unifying relativity, quantum mechanics, entropy, and time's arrows and assymetries with a new universal invariant: dx4/dt=ic."
Eppur si muove!
Dr. E (The Real McCoy)
"Books on physics are full of complicated mathematical formulae. But thought and ideas, not formulae, are the beginning of every physical theory." --Einstein/Infeld, The Evolution of Physics
MDT's *physical* idea: the fourth dimension is expanding relative to the three spatial dimensions at c, or dx4/dt=ic.
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Chris Kennedy wrote on Dec. 22, 2008 @ 15:04 GMT
Do I smell a potential confrontation brewing here? I haven’t seen anything like this since Apollo Creed tried to get Rocky Balboa back in the ring for a rematch. Can you imagine the excitement that a debate would bring:
Ladies and Gentlemen – Now for the main event. In this corner, we have our challenger:
He’s the master of moving dimensions – Elliot “The Real McCoy” McGuckennnnn!
And in this corner: With the best overall combination of restricted and public votes so far - The Thermodynamical Wonder – Carlo “Leave your wristwatch at home” Rovelllllli!
Okay guys, normally, I would recommend a twelve round debate(three minutes each) but since none of us are sure of what the nature of time is yet - just come out typing when you hear the sound of the bell and keep going until we have a winner.
Good luck!
Narendra Nath wrote on Dec. 22, 2008 @ 16:43 GMT
Vasseline, George and Rovelli,
What is deterministic in this Universe is the Universe itself with whatever it unfolds before us. Science of Physics is not deterministic , as it attempts to evolve some concepts to understand what is observed to be happening in this universe of ours. We only try to understand how the things are happening and not the why's. The observed facts are supreme and any theoretical model that we may evolve based on limited facts and not the entirety of observed facts. That is we need consistency when we explain one phenomenon, with explanations provided for other observed phenomena too.
As i understand it, the block universe and the Expanding Block Universe are one and the same. It is just a difference that in the former time is a parameter while in the latter it is intrinsically built into the explanation. Thus, i don't see any scope for personal confrontations, as our individual opinions have little significance unless born out by experimental facts that have been confirmed reasonably well by independent research workers. That much is enough as we seek better and better relative truths in Physics about the various physical phenomena as such. May i just say that it may not be wise to conclude that we have understood the working of the human brain fully through Physics 'alone'. The human mind and the human 'soul' do not entirely lie in the domain of current Physics. The Nobel winner, Prof. Eccles of Oxford while studying the neuron activity of the Supplementary Motor Area (SMA) of the brain observed activity when none was expected from within the body involved. He asserted that there appears to be a non-physical sheath that surrounds the SMA that is capable of recording such outside interactions that the neurons in SMA are experiencing. He further believes that this non-physical covering survives with such a record of 'outside interactions' beyond the death of that body!
Let us therefore keep our discussions open in a reasonable way to permit later innovations, instead of making categorical statements about the finality of any approach or explanation. i am sorry if anyone takes me as personally critical of another person, as i myself can not be absolutely sure about things that i am supposed to know well.
amrit wrote on Dec. 23, 2008 @ 15:11 GMT
Der Dr Rovelli
Science can not exist without time, we just have to give time right position in scientific models of the universe.
My recent idea is that time is a "coordinate of motion".
Theory of Relativity describes motion of elementary particles and massive bodies. With clocks one measures duration and numerical order of this motion. Time is what is measured with clocks: the duration and the numerical order of motion of elementary particles and massive bodies in space. In the Theory of Relativity time as a “fourth coordinate” describes motion of massive objects and elementary particles in space. In that sense fourth time coordinate is the “coordinate of motion”. Time is not a part of space. Space-time is not a physical reality into which material change run. Space-time is a math model only used for description of motion of objects in space where time is a coordinate of motion. Space itself is atemporal.
attachments:
In_The_Theory_of_Relativity_Time_is_a_Coordinate_of_Motion__Sorli_2009.pdf
Narendra Nath wrote on Dec. 28, 2008 @ 05:52 GMT
Awaiting response if any on my post of Dec., 22, 2008
F. Le Rouge wrote on Dec. 31, 2008 @ 19:55 GMT
- Opinion of C. Rovelli (December 12) that one can easily get rid of Space at a fundamental level... this opinion is just incredible!
It proves that Rovelli's algebraic idea of Space is based... on Time idea (Words/Language), no matter the kind of scale he is choosing, boiling water in a valley or on top of a mountain.
- Of course Aristotle has nothing to do with Rovelli, Aristotle for whom Space IS Matter, Water, Ether or other elements. Time is for Aristotle deforming Matter.
- But Descartes cannot be quoted here by Rovelli either. Descartes wants to get rid of TIME in his ballistic ('Essay on Static') experiences. Even if Descartes did not understood some of Aristotle's lessons, he is aware of the relationship between matter and space that Scientists mostly are stating: distances in the Universe are often deduced on Spheric Earth or Moon dimensions; and if World is not 'fundamental'?
- And Newton cannot be asked for help by Rovelli too, even if Newton principles are somewhere ambiguous like Descartes principles. Here must the metaphysical Ether be evoked because Space is collapsing on this point (Is Ether full or empty Space?).
Debate between Huygens and Netwon about Ether is Christian metaphysical Debate.
- Rovelli has more to do with G. Berkeley for whom language is more real than reality itself, or with Einstein General Relativity (and E=mc2 in which matter and space are conjured away). Problem of Rovelli is that he wants to forget Einstein on whom he is based. He is catched in the reference as a fly on a web.
'Dualism' of Rovelli or String theoricians is this one: when he is speaking about metaphysics: this is ballistic science; but when he is speaking about ballistic science: this is metaphysics.
F. Le Rouge wrote on Dec. 31, 2008 @ 20:08 GMT
When you tell me that my point of view is 'refreshing', Narendra Nath, do you mean like the refreshing comment of the child in the Andersen Tale: 'But the King is naked!'
Narendra Nath wrote on Jan. 1, 2009 @ 13:47 GMT
Le Rouge, i just mean that it is both meaningful and innovative, with little bias from what is 'known'. i am not familiar with Anderson Tale, may be i have forgotten. Therefore, your quote from there is out of context for me. Never mind, the essay discussion soon closes and i wish you and all other authors the best of life ahead.
Member Antony Garrett Lisi wrote on Jan. 2, 2009 @ 03:12 GMT
Hello Carlo,
I've been impressed by your thermal time hypothesis ever since I first encountered it in your book. And here you've done an excellent job of presenting it with some fresh points of view. Thanks for this contribution.
Best,
Garrett
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F. Le Rouge wrote on Jan. 3, 2009 @ 14:02 GMT
- I want to be clearer on the big mistake that Carlo Rovelli is making about Aristotle's Physics.
Opinion of Rovelli is that space is empty.
Opinion of Aristotle is that space is full (of matter).
As there is no emptiness in Aristotle's Physics drives Rovelli to think that there is no space in Aristotle.
Therefore Algebraic method is deeply criticized by Aristotle.
- What is the problem with such a mistake about Aristotle? The problem is that you cannot understand Newton, Huygens or Descartes without understanding Aristotle. Newton principles are not entirely logic but he is partly sharing with Aristotle the idea that space is matter, especially on the hot spot of Light which is for Newton Matter. Idea of Light beeing both a wave and a particle is a nothing else than a Compromise.
- About G. Lisi's Theory that I dicovered in French press, close to D. Bundy's Theory in this forum, I notice that this theory is not far away from Rovelli's.
What did Descartes do? He translated Geometric drawings in Algebraic numbers (History of Art/Painting from XVIIth is governed by the same idea). What are Lisi or Bundy doing? They translate Algebraic numbers in Geometric drawings.
Why this symmetric turning round? Because of the cul-de-sac of fundamental Mathematics.
And Albebraic geometry is for sure more difficult to call in question again for Modern Mathematics than for his Creator to kill Frankenstein (New metaphor for open-minded Narendra Nath).
Gianluca wrote on Jan. 5, 2009 @ 01:30 GMT
Dear Prof. Rovelli,
I find your views about time extremely clear and rational and you contributed in developing my understanding of a world ontology not dependent on time. Now I hit randomly a short text by Lee Smolin at http://www.edge.org/q2009/q09_9.html#smolin where he affirms with sudden certainty presentism & time realism. Since you know well Lee Smolin, do you know which could be the rational basis of such a radically opposite view and which is your viewpoint on it? Please restore my shaken faith in a timeless reality (is Lee the Devil?)
Sincerely, and I wish you a happy 2009.
Dr. E (The Real McCoy) wrote on Jan. 7, 2009 @ 23:13 GMT
Happy New Year All!
I too recently came across Lee's piece:
http://www.edge.org/q2009/q09_9.html#smolin
"THE LIBERATION OF TIME"
Moving Dimensions Theory has been liberating time for quite some time now. Check it out where I used the word "liberate" at:
http://fqxi.org/community/forum/topic/238
"Dr. E wrote on Sep. 11, 2008 @ 15:18 GMT
...
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Happy New Year All!
I too recently came across Lee's piece:
http://www.edge.org/q2009/q09_9.html#smolin
"THE LIBERATION OF TIME"
Moving Dimensions Theory has been liberating time for quite some time now. Check it out where I used the word "liberate" at:
http://fqxi.org/community/forum/topic/238
"Dr. E wrote on Sep. 11, 2008 @ 15:18 GMT
. . . Yes--perhaps you can interpret it that way, but for the moment I'm trying to keep things as simple as possible, by stating that the fourth dimension is expanding relative to the three spatial dimensions: dx4/dt=ic. Einstein's Relativity may be derived from this simple postulate and its equation, and too, it unfreezes time, it liberates us from the block universe, and it accounts for quantum mechanics' nonlocality and entangelment, as well as entropy and time's arrows in all realms.
There may be many ways of interpreting a fourth expanding dimension, as you suggest. What do you mean by "quantum constant?"
I propose that a fundamental invariant of the universe is dx4/dt = ic. It is this deeper reality that leads to the constancy of c--both its independence of the velocity of the soure and the fact that it is measured to be c for all observers. dx4/dt = ic accounts for both of these c's in different ways, with the same physical model. It does not simply state that c is constant, but it also states "why."
Time--the t in dx4/dt--is the time we're all so used to--the time we see ticking away on our watches. Now this time is typically measured by some process that involves the propagation of photons, or changes in energy, be it an unwinding clock spring, an oscillating quartz crystal, or an electronic circuit. t is then ultimately tied to the propagation of photons, which are just matter surfing the fourth expanding dimension. And so it is that relativity's math inherits this notion of the fourth dimension, as relativity was born by comntemplating the propagation of light--photons. We define time by the propagation of light, and then we measure the propagation of light via time. This tautology has lead to c's constancy and too, one can see how it is the fount of realtivity's beauty--for think of the very word "relativity." It means that the way we measure physical reality is "relative" to how we are moving through space-time. Does it not make sense that measurements utilizing meter sticks, clocks, and light should be relative to motion, when both the clocks as well as the light depend on photons, which are surfing the fourth expanding dimension, which meter sticks are rotated into, and thus foreshortened in our three spatial dimensions, whenever they move? But yet, there are invariant entities, such as interval, c, and rest mass, and that's what physics has always truly been about--the rock-hard invariance of a physical reality.
MDT proposes a deeper invariance dx4/dt = ic, from which the invariance of c and the invariance of interval both naturally emerge."
It's good to see Lee has changed his view and is now accepting time's reality, for the moment, at least!
Lee writes at The Edge, "I would like to describe a change in viewpoint, which I believe will alter how we think about everything from the most abstract questions on the nature of truth to the most concrete questions in our daily lives. This change comes from the deepest and most difficult problems facing contemporary science: those having to do with the nature of time. . . . There is also no past. The past only lives as part of the present, to the extent that it gives us evidence of past events. And the future is not yet real, which means that it is open and full of possibilities, only a small set of which will be realized. Nor, on this view, is there any possibility of other universes. All that exists must be part of this universe, which we find ourselves in, at this moment." --http://www.edge.org/q2009/q09_9.html#smolin
Best,
Dr. E (The Real McCoy)
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Narendra Nath wrote on Jan. 9, 2009 @ 07:03 GMT
Dear Le Rouge,
On this essay post,you have raised me to the level of Frankestein, an open minded monstor. i would have liked you to leave me at a much lower level. What you feel we know about the universe through science at present? i may say we know a negligible amount, inspite of the 'tremendous'progress science & technology, its sister, has made! Without the broadest of thinking one can never expect to overcome the huge gap between total knowledge and the existing knowledge that we have attained about the Universe. We often find that what we knew in science about the moon, the nearest object to the Earth, changes drastically as we perform more and more expts. on the moon with the instruments. The latest mission has been done by India and it has succeeded in identifying the sources of water and helium3 on the moon.That si going to provide a big boost to exploit the resources on the moon for our comfort on the earth. This will go on and i know we have lot of surprises in store for us about our sister planets on our solar system too than what we claim to know presently. Thus, it is best to say we know very little and keepmour minds open for future unknowns that exist in plenty.
F. Le Rouge wrote on Jan. 9, 2009 @ 09:20 GMT
- 'Open minded', Narendra, because I bet with my friends before this contest that no one on the fqxi forum would talk with someone (me) who says that Engineering is not Science but a bad mixing of Technology and -let us say- 'Ballistic Metaphysics'; with someone (me) who says that Isaac Newton is wrong, especially his gravitation Theory. (But if you read Newton's principles you will see that Rovelli does believe more in Newton that Newton himself believe in gravitation.)
- 'Frankenstein' because Algebraic geommetry is a monster, entirely created by Scientists and who is 'escaping' now. Two examples:
. Usefulness of fractal numbers for instance is entirely subjective, related with the attempt to square one's circle. But notice that this 'subjectivity', Narendra, has become almost objective.
. Second example is Feynman when he says something like: 'Nobody is able to understand Quanta Physics': I translate: nobody is out of the reference, the ratio between engineers and the machine. Again: This is Pythagorean Science and its monster Frankenstein!
- You are sharing the same paradox than Rovelli: he is wanting more 'objectivity' and less 'cognition' and so suggests to forget the Time... but he keeps it although as nothing less than a World dimension! It is difficult to be more subjective, please admit it. And because Aristotle has not the same idea of (empty) Space than Rovelli, does it mean that Aristotle does not care about Space?
You are closer to Einstein or Bergson, Narendra, who intended to put more Spirituality in Empiricim, to put more Time in Mechanics. Due to your Indian Natural Philosophy I guess, you are not far away from the lutherian spirituality that inspired Huygens or Einstein: as death is just a 'new start', Time is not a negative value for you. You do ignore another kind of spirituality in which Time is a negative value, a kind of 'Sympathy for the Devil'.
- When you say that Technology is the Sister of Science, you should not forget that millions of people that did not share the ballistic spirituality died because of it.
I make one's peace with you here Narendra, on the huge gap between total knowledge and what Engineers think the real World is throughout their computers and lenses.
petm1 wrote on Feb. 18, 2009 @ 22:44 GMT
Think of our clocks as measuring the intrinsic motion of the same systems governed by the laws of thermodynamics. Think of our clocks as counting the events, and temperature as a measure of the duration of the events themselves. The shorter the duration of an event the more events you can fit into the same amount of time. With these two ways to measure the present wouldn’t you think that the rule of local clocks ticking at the same rate, and thermal equilibrium might be two ways to look at the same thing?
Dr. E (The Real McCoy) wrote on Feb. 25, 2009 @ 15:11 GMT
Hello Carlo!
Hope all is well with you!
Just reread your paper and I got to thinking that quantum gravity is indeed the father of so many wrong directions--from Einstein's later years whence he abandoned *physical* models in favor of pure math to String Theory to LQG. Too often quantum gravity is treated as something *real*--its existence is assumed to be *real*--and this...
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Hello Carlo!
Hope all is well with you!
Just reread your paper and I got to thinking that quantum gravity is indeed the father of so many wrong directions--from Einstein's later years whence he abandoned *physical* models in favor of pure math to String Theory to LQG. Too often quantum gravity is treated as something *real*--its existence is assumed to be *real*--and this "reality" is then used as a foundation for one's theorizing and contemplations. But nobody has ever quantized grvaity nor seen a graviton, and in this paper I show there is no need to quantize gravity:
http://fqxi.org/data/forum-attachments/9_MOVING_DIME
NSIONS_THEORY_EXAMINES_THE_GRAVITATIONAL_REDSHIFT_SLOWING_OF
_CLOCKS.pdf
In your paper you write, "I have here attempted to combine a coherent view about the problem of time in quantum gravity, starting from what others have understood."
Is time really a problem in quantum gravity when nobody has ever quantized gravity and nobody has ever seen a graviton, nor quite knows how we might even see or measure one? Indeed--Freeman Dyson suggested that it might be impossible in principle to measure a graviton. Ergo, contemplating time in the realm of quantum grvaity, when quantum grvaity might not exist, may lead us down wrong paths. Hundreds of millions have been spent on these paths which have so far lead nowhere.
I would suggest there are more optimum paths to follow--paths that begin by contemplating foundational questions--paths that are motivated by providing a simple, unifying *physical* model for both quantum mechanics' "characteristic trait" and relativity's "elementary foundations" which Einstein yet sought. MDT, by providing a *physical* model from where such entities emerge, also provides the mechanism from which time naturally emerges.
MOVING DIMENSIONS THEORY: EXALTING EINSTEIN’S ELEMENTARY FOUNDATIONS & SCHRODENGER’S CHARACTERISTIC TRAIT
by Dr. Elliot McGucken
http://fqxi.org/community/forum/topic/238
"A physical theory can be satisfactory only if its structures are composed of elementary foundations. The theory of relativity is ultimately as little satisfactory as, for example, classical thermodynamics was before Boltzmann had interpreted the entropy as probability. –Einstein in a letter to Arnold Sommerfield on January 14th, 1908. CPAE, Vol. 5, Doc. 73:"
"When two systems, of which we know the states by their respective representatives, enter into temporary physical interaction due to known forces between them, and when after a time of mutual influence the systems separate again, then they can no longer be described in the same way as before, viz. by endowing each of them with a representative of its own. I would not call that one but rather the characteristic trait of quantum mechanics, the one that enforces its entire departure from classical lines of thought. By the interaction the two representatives [the quantum states] have become entangled." --Schrödinger
Moving Dimensions Theory’s simple postulate, physical model, and equation account for both “relativity’s elementary foundations,” which Einstein stated we yet needed, and Schrödinger’s “characteristic trait” of quantum mechanics—entanglement.
MDT: The fourth dimension is expanding relative to the three spatial dimensions at the rate of c, or dx4/dt=ic.
"If we are to go forward, we must go back and rediscover those precious values - that all reality hinges on moral foundations and that all reality has spiritual control." –Martin Luther King Jr.
Physics has ever been driven and advanced by physicists contemplating *physical* reality and presenting *physical* models, in the rugged pursuit of fundamental *physical* principles.
"My interest in science was always essentially limited to the study of principles.... That I have published so little is due to this same circumstance, as the great need to grasp principles has caused me to spend most of my time on fruitless pursuits." --Einstein
Einstein's Principle of Relativity (the first postulate), as well as the second postulate of relativity, both derive from MDT's single postulate which is more concise and has the added benefits of providing for free will, liberating us from the block universe, weaving change into the fundamental fabric of spacetime for the first time in the history of relativity, and providing a *physical* model for time and all its arrows and asymmetries, entropy, and quantum nonlocality and entanglement, as well as reality's probabilistic nature. The fourth dimension is inherently nonlocal via its invariant expansion, and thus “quantum mechanics’ characteristic trait” (in Schrödinger’s words) naturally emerges.
1. First postulate (principle of relativity)
The laws by which the states of physical systems undergo change are not affected, whether these changes of state be referred to the one or the other of two systems of coordinates in uniform translatory motion.
2. Second postulate (invariance of c)
Light is always propagated in empty space with a definite velocity c that is independent of the state of motion of the emitting body.
Both of these postulates—as well as the Einstein/Minkowski spacetime metric—naturally derive from MDT’s simple postulate and equation: the fourth dimension is expanding relative to the three spatial dimensions at c, or dx4/dt=ic. The derivation of relativity and motivation for replacing x4 with ict may be seen here:
http://fqxi.org/community/forum/topic/238
Time as an Emergent Phenomenon: Traveling Back to the Heroic Age of Physics by Elliot McGucken
MDT presents a new universal invariant--an elementary law from which Einstein's Principle of Relativity can be built by pure deduction. Begin with a universe with four dimensions x1, x2, x3, x4, where the fourth dimension is expanding relative to the three spatial dimensions dx4/dt=ic, and the Minkowski/Einstein spacetime metric and all of relativity naturally emerge, as does quantum mechanics' nonlocality and entanglement, wave-particle duality, space-time duality, mass-energy duality, E/B duality, entropy, and time and all its arrows and asymmetries.
"Behind it all is surely an idea so simple, so beautiful, that when we grasp it - in a decade, a century, or a millennium - we will all say to each other, how could it have been otherwise? How could we have been so stupid?" --John A. Wheeler
MDT presents a physical principle more fundamental than Einstein's principle of relativity, as all of relativity naturally emerges from MDT's postulate, as well as entanglement and quantum mechanics’ probabilistic nature.
Please see the attached PDF for the rest.
Hope all is well!
Best,
Dr. E (The Real McCoy)
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attachments:
1_ja_wheeler_recommendation_mcgucken_medium2.jpg,
1_physics5.pdf
amrit wrote on Mar. 18, 2009 @ 18:32 GMT
motion runs in timeless universe
time has origin in the human mind
with clock we measure duration of motion in timeless universe
attachments:
5_ETERNITY_IS_NOW_Sorli_2009.pdf
Wilton Alano replied on Jul. 4, 2010 @ 18:31 GMT
Dear Amrit,
Time means that matter in motion is - in the 'present' moment - in a different spacial position than 'before'. As you must know, it happens to any corpse or particle spinning or in spatial trajectory.
So, time means that a system is energized and, therefore, in motion and truly real; instead of a just "an human mind construction".
(* "Energy" means inertial motion of corpses or particles).
Alejandro Rivas-Micoud wrote on Dec. 30, 2010 @ 09:28 GMT
Dear Dr. Rovelli,
What if time is simply the means by which random chance “collapses” a wave probability for a specific segment of space/matter? In other words, is entropy simply the means by which gradually a set of probabilistic outcomes randomly occur throughout space? Thus making time a consequence of random chance gradually collapsing from its wave function into an observable state? The past as observed “collapsed” particles? The future as non observed probability waves? The present as observation of the collapse of a specific space/matter segment? Energy, the consequence of observation? Matter, the result of the action of time on space? In other words, if the future were known, then time would not exist?
Rodney Bartlett wrote on Jan. 30, 2011 @ 12:32 GMT
Dear Dr. Rovelli,
Here's a post that tries to comment on FQXi's 2008 essay contest (The Nature of Time) as well as its 2010 essay contest (Is Reality Digital or Analog?)
We have to wonder if the Large Hadron Collider was worth all the time and money it took to build. It won't find the Higgs boson. It may well "prove" that strings exist but this will only deceive the world because...
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Dear Dr. Rovelli,
Here's a post that tries to comment on FQXi's 2008 essay contest (The Nature of Time) as well as its 2010 essay contest (Is Reality Digital or Analog?)
We have to wonder if the Large Hadron Collider was worth all the time and money it took to build. It won't find the Higgs boson. It may well "prove" that strings exist but this will only deceive the world because strings are only a tiny fraction of matter's true composition. Perhaps it would have been better to spend the money buying several million desktop computers for scientists to develop and refine theories with.
ALTERNATIVE TO HIGGS BOSON
An important step might be to think of "... the grand design of the universe, a single theory that explains everything" (words used by Stephen Hawking on the American version of Amazon, when promoting his latest book “The Grand Design” – coauthored with Leonard Mlodinow, Bantam Books, 2010) in a different way than physicists who are presently working on science's holy grail of unification. The universe’s underlying electronic foundation* (which makes our cosmos into a partially-complete unification, similar to 2 objects which appear billions of years or billions of light-years apart on a huge computer screen actually being unified by the strings of ones and zeros making up the computer code which is all in one small place) would make our cosmos into physics’ holy grail of a complete unification if it enabled not only elimination of all distances in space and time, but also elimination of distance between (and including) the different sides of objects and particles. This last point requires the universe to not merely be a vast collection of the countless photons, electrons and other quantum particles within it; but to be a unified whole that has “particles” and “waves” built into its union of digital 1’s and 0’s (or its union of qubits – quantum binary digits). If we use the example of CGH (computer generated holography, which is reminiscent of the holographic simulation called the Holodeck in “Star Trek: The Next Generation”), these "particles" and "waves" could be elements produced by the interaction of electromagnetic and presently undiscovered gravitational waves, producing what we know as mass and forming what we know as space-time. Einstein predicted the existence of gravitational waves, and measurements on the Hulse-Taylor binary-star system resulted in Russell Hulse and Joe Taylor being awarded the Nobel Prize in Physics in 1993 for their work, which was the first indirect evidence for gravitational waves. The feedback of the past and future universes into the unified cosmos's electronic foundation would ensure that both past and future could not be altered. (Our brains and minds are part of this unification too, which must mean extrasensory perception and telekinetic independence from technology are possible.)
* For more information on the universe's proposed electronic foundation, please see my article and postings at
http://fqxi.org/community/forum/topic/814
as well as my replies to Dr. Israel Omar Perez at
http://fqxi.org/community/forum/topic/817
STRINGS ARE ONLY PART OF MATTER'S BASIS
Space and time only exist in our experience. They are emergent properties, like wetness and mind. We experience wetness because it emerges from the building blocks of the hydrogen and oxygen atoms which make up water. We experience mind because it emerges from the building blocks of neurons composing the brain. And we experience space-time since it emerges from the building blocks making up the universe. These units are a combination of electromagnetic pulses (forming a cosmic computer which includes randomness and thus the potential to escape rigid preprogramming, and have a small degree of free will) as well as a cosmic hologram (this is produced by the interaction of electromagnetic plus gravitational waves and combination of the holographic aspect with the electronic aspect unifies general relativity with quantum physics). Every physical and nonphysical part of the universal hologram would be a receptor for the downloading of data from the cosmic computer which not only exists in the hyperspace of the large-scale universe but also in the hyperspace of each subatomic particle. (In other words, the holographic universe or spacetime we know is a screen for displaying data from the 5th-dimensional computer).
It might be helpful to visualise time as the playing of a CD or video tape. The entire disc or tape obviously exists all the time. But our physical senses can only perceive a tiny part of the sound and the sights at any fraction of a second. I believe space and time are infinite, so it might be more accurate to visualise time as that HUGE number - in this case, of CDs or tapes - which some versions of string theory propose (at a minimum, 10 exponent 500). My essay - http://fqxi.org/community/forum/topic/814 - tells you how to travel to the future, how to return home, and how to travel into our past. Neither future nor past can be altered (a blow to our belief that we have the free will to shape the future) and my explanation of travel to the past requires re-interpretation of the concepts of "multiverse" and "parallel universes". It also requires the ability to travel billions of light years INSTANTLY. This sounds like pure fantasy, but I outline an approach based on electrical engineering, General Relativity, and Miguel Alcubierre's 1994 proposal of "warp drive" that makes it logically possible.
These unbelievable things are made believable if you read my essay (along with its postings and replies) as well as the little books I've written (listed in the essay's Endnotes). But if you don't have time to read all that (I don't think I do!), here's a little picture that tries to summarise everything in a few lines -
My essay suggests the universe is a Mobius loop and is contained in, or unified with, each of its particles (relying on physical senses or 21st-century scientific instruments would make this statement ridiculous). Then each fermion and boson would also be composed of the 3 spatial dimensions, the 4th dimension of time, and the 5th dimension of hyperspace. Detectors like the Large Hadron Collider would be unable to "see" the time and hyperspace components of particles but could only see the small (maybe 5%) 3 spatial dimensions (the time and hyperspace components would be what we call dark matter), erroneously assuming particles are those tiny fractions of a Mobius loop that physics calls strings. "Dark matter" would exert a gravitational influence because both time and hyperspace, being parts of a curved Mobius loop (whether of quantum or cosmic scale), would push objects together in the same way Einstein's curved space-time pushes objects together. We can speak of the HST now - no, not the Hubble Space Telescope but Hyperspatial SpaceTime. We can visualise the Mobius loop as composed of a hyperspace computer which generates information on how things change from one undetectably tiny fraction of a second to the next (we call this time, and it's comparable to the frames in a movie) and transmits the data (transmits dark energy?) to the insignificant portion of length, width and depth that makes up subatomic particles ... and the universe.
That's the end of my one-paragraph summary. Now for some extra thoughts that popped into my head -
Preceding the Big Bang (which created this local section of the infinite, eternal universe ... or if you prefer, this subuniverse of the megauniverse) there would have been no space, matter or time in this subuniverse and all would have been hyperspace. No transmissions of dark energy (creating time and space/matter) would have occurred - therefore the dark-energy content of the universe would have been zero, increasing to the present 72% as more and more matter was created. How is matter created? Perhaps as cosmologist Alan Guth once suggested -
"You might even be able to start a new universe using energy equivalent to just a few pounds of matter. Provided you could find some way to compress it to a density of about 10^75 (10 exponent 75) grams per cubic centimeter, and provided you could trigger the thing ..."
At the time the Cosmic Microwave Background was emitted (less than a million years after the big bang), results from the Wilkinson Microwave Anisotropy Probe say the dark-energy content of the universe was negligible. Space/matter has been increasing since the big bang so transmissions from hyperspace (dark energy) which create them are increasing while the volume of the Mobius loop occupied by time/hyperspace (dark matter) has been shrinking as a result - according to the WMAP satellite, from 63% when the CMB was emitted to 23% today. Why isn't dark energy increasing at the same rate dark matter is decreasing? It must be because, as stated earlier, both time and hyperspace exert a gravitational influence, thereby mimicking space and matter to a degree. This mimicry causes the dark matter between the start of the CMB and the present to decrease by only about 40% while dark energy increases in the same period by about 70%.
My essay tells you how to travel into the future, how to return home, and how to take a trip into our past. Regarding travel beyond our start and into the past ... it can’t be denied that these paragraphs imply the possibility of humans from the distant future time-travelling to the distant past and using electronics to create this particular subuniverse's computer-generated Big Bang. An accomplishment such as this would be the supreme example of “backward causality” (effects influencing causes) promoted by Yakir Aharonov, John Cramer and others. However, realising that we live in a cosmic-quantum unification with zero-separation and recalling Isaac Newton’s inverse-square law and what it says about the force between two particles being infinite (does infinite mean 10 ^ 500, the HUGE number of universes proposed by some versions of string theory?) if the distance of separation goes to zero means there's still room for God (as Creator) because God would be a pantheistic union of the megauniverse's material and mental parts, forming a union with humans in a cosmic unification.
Best wishes,
Rodney Bartlett
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Rodney Bartlett wrote on Feb. 2, 2011 @ 03:27 GMT
I know I can't submit another essay. I don't plan to - these are just some comments that came to mind after thinking about my essay. They don't seem very relevant to the topic "Is Reality Digital or Analog?" but writing them has given even more satisfaction than writing the essay, and I'm in the mood to share them with the whole world. So if you've got time to read them...
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I know I can't submit another essay. I don't plan to - these are just some comments that came to mind after thinking about my essay. They don't seem very relevant to the topic "Is Reality Digital or Analog?" but writing them has given even more satisfaction than writing the essay, and I'm in the mood to share them with the whole world. So if you've got time to read them ...
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I fully realise that my essay doesn’t sound like science at all. I can appreciate that many readers think it belongs to science fiction and fantasy. It does have saving graces though. I’m amazed at how well it fits in with the discoveries of the Microwave Anisotropy Probe and with string theory, culminating in the LHC’s experimentally verified strings and my prediction of antistrings. Having said that, I must say this – it’s very strange that the scientific world is so obsessed with mathematics (admittedly, my essay did dabble with it when offering a version of E=mc2 to suit the digital world - but I kept it very simple ... so simple it might be regarded as wrong). Math seems to be regarded as infallible, even though it leads to mistakes. The (partial) mistake I have in mind is string theory. I don't deny that there certainly is value in the theory, and in maths, but logic reveals shortcomings. Let me explain, after first writing a short section describing an unconventional approach to unveiling unification and offering an alternative to the Higgs boson that relies on gravitational waves.
ALTERNATIVE TO HIGGS BOSON
An important step might be to think of "... the grand design of the universe, a single theory that explains everything" (words used by Stephen Hawking on the American version of Amazon, when promoting his latest book “The Grand Design” – coauthored with Leonard Mlodinow, Bantam Books, 2010) in a different way than physicists who are presently working on science's holy grail of unification. The universe’s underlying electronic foundation* (which makes our cosmos into a partially-complete unification, similar to 2 objects which appear billions of years or billions of light-years apart on a huge computer screen actually being unified by the strings of ones and zeros making up the computer code which is all in one small place) would make our cosmos into physics’ holy grail of a complete unification if it enabled not only elimination of all distances in space and time, but also elimination of distance between (and including) the different sides of objects and particles. This last point requires the universe to not merely be a vast collection of the countless photons, electrons and other quantum particles within it; but to be a unified whole that has “particles” and “waves” built into its union of digital 1’s and 0’s (or its union of qubits – quantum binary digits). If we use the example of CGH (computer generated holography, these "particles" and "waves" could be elements produced by the interaction of electromagnetic and presently undiscovered gravitational waves, producing what we know as mass and forming what we know as space-time. Einstein predicted the existence of gravitational waves, and measurements on the Hulse-Taylor binary-star system resulted in Russell Hulse and Joe Taylor being awarded the Nobel Prize in Physics in 1993 for their work, which was the first indirect evidence for gravitational waves. The feedback of the past and future universes into the unified cosmos's electronic foundation would ensure that both past and future could not be altered. Our brains and minds are part of this unification too - which must mean extrasensory perception and telekinetic independence from technology are possible, despite modern science's objections to these phenomena which appear to be based on non-unification.
* For more information on the universe's proposed electronic foundation, please see my article and postings at
http://fqxi.org/community/forum/topic/814
STRINGS ARE ONLY PART OF MATTER'S BASIS
Space and time only exist in our experience. They are emergent properties, like wetness and mind. We experience wetness because it emerges from the building blocks of the hydrogen and oxygen atoms which make up water. We experience mind because it emerges from the building blocks of neurons composing the brain. And we experience space-time since it emerges from the building blocks making up the universe. These units are a combination of electromagnetic pulses (forming a cosmic computer which includes randomness and thus the potential to escape rigid preprogramming, and have a small degree of free will) as well as a cosmic hologram (this is produced by the interaction of electromagnetic plus gravitational waves and combination of the holographic aspect with the electronic aspect unifies general relativity with quantum physics). Every physical and nonphysical part of the universal hologram would be a receptor for the downloading of data from the cosmic computer which not only exists in the hyperspace of the large-scale universe but also in the hyperspace of each subatomic particle. (In other words, the holographic universe or spacetime we know is a screen for displaying data from the 5th-dimensional computer.)
It might be helpful to visualise time as the playing of a CD or video tape. The entire disc or tape obviously exists all the time. But our physical senses can only perceive a tiny part of the sound and the sights at any fraction of a second. I believe space and time are infinite, so it might be more accurate to visualise time as that HUGE number - in this case, of CDs or tapes - which some versions of string theory propose (10 exponent 500). My essay tells you exactly how to travel to the future, how to return home, and how to travel into our past. Neither future nor past can be altered (a blow to our belief that we have the free will to shape the future) and my explanation of travel to the past requires re-interpretation of the concepts of "multiverse" and "parallel universes". It also requires the ability to travel billions of light years INSTANTLY - no doubt many readers will instantly dismiss the essay because their preconceptions "know" this simply isn't possible. It indeed sounds like pure fantasy, but I outline an approach based on electrical engineering, General Relativity, and Miguel Alcubierre's 1994 proposal of "warp drive" that makes it logically possible.
My essay explains why the universe is a Mobius loop and how it is contained in, or unified with, each of its particles (relying on physical senses or 21st-century scientific instruments would make this statement ridiculous). Then each fermion and boson would also be composed of the 3 spatial dimensions, the 4th dimension of time, and the 5th dimension of hyperspace. Detectors like the Large Hadron Collider would be unable to "see" the time and hyperspace components of particles but could only see the small (maybe 5% of the whole) 3 spatial dimensions (the time component would be what we call dark matter), erroneously assuming particles are those small fractions of a Mobius loop that physics calls strings. "Dark matter" would exert a gravitational influence because time, being part of a curved Mobius loop (whether of quantum or cosmic scale), would push objects together in the same way Einstein's curved space-time pushes objects together. We can speak of the HST now - no, not the Hubble Space Telescope but Hyperspatial SpaceTime. We can visualise the Mobius loop as composed of a hyperspace computer which generates information on how things change from one presently undetectably tiny fraction of a second to the next (we call this time, and it's comparable to the frames in a movie) and transmits the data (transmits dark energy) to the insignificant portion of length, width and depth that makes up subatomic particles ... and the universe.
Preceding the Big Bang (which created this local section of the infinite, eternal universe ... or if you prefer, this subuniverse of the megauniverse) there would have been no space, matter or time in this subuniverse. No transmissions of dark energy (creating time and space/matter) would have occurred - therefore the dark-energy content of the universe would have been zero, increasing to the present 72% as more and more matter was created. How is matter created? Perhaps as cosmologist Alan Guth once suggested -
"You might even be able to start a new universe using energy equivalent to just a few pounds of matter. Provided you could find some way to compress it to a density of about 10^75 (10 exponent 75) grams per cubic centimeter, and provided you could trigger the thing ..."
At the time the Cosmic Microwave Background was emitted (less than a million years after the big bang), results from the Wilkinson Microwave Anisotropy Probe say the dark-energy content of the universe was negligible. Space/matter has been increasing since the big bang so transmissions from hyperspace computer (dark energy) which create them are increasing while the volume of the Mobius loop occupied by time/hyperspace (dark matter) has been shrinking as a result - according to the WMAP satellite, from 63% when the CMB was emitted to 23% today. Why isn't dark energy increasing at the same rate dark matter is decreasing? It must be because, as stated earlier, both time and hyperspace exert a gravitational influence, thereby mimicking space and matter to a degree. This mimicry causes the dark matter between the start of the CMB and the present to decrease by only about 40% while dark energy increases in the same period by about 70%. If we were dealing with a simple and ordinary loop, this similarity would cause dark matter and dark energy to be more or less equal and if there was any difference in their amount of decrease/increase, it would be in the same direction. But we’re talking about Mobius loops which are like strips of paper that have been twisted 180 degrees before the ends are joined. This causes their variation to go in different directions (one increases, the other decreases) and the amount of variation is quite significant (+72%, -40%). My guess is that the real-life twist occurs in the temporal segment of the loop, enabling a traveller in time to go in different directions i.e. into the future or into the past. To replenish dark matter in billions of years, we merely have to extend Guth's proposal by using the knowledge of that time to create more matter.
A real-life Mobius is by no means a featureless loop, however. If, contrary to our impressions, the universe is unified with each particle it’s composed of; the WMAP satellite’s findings must apply to the quantum world. The figures 72%, 23% and 5% would not only describe the present universe’s content of dark energy, dark matter and ordinary matter but also any particle’s content of space or ordinary matter (5%), time or dark matter (23% - time is considered to be dark matter here because dark matter is regarded as ordinary matter invisible to us since it’s present in another region of the dimension we call time, just as most of a sphere is in another dimension and consequently appears as a dot when first entering Edwin Abbott’s 1884 exploration of other dimensions called “Flatland”), and hyperspace (72%: the transmissions from the hyperspace computer create space and matter, cause expansion of space on cosmic scales where there are no forces to overcome the expansion as there is in matter, and are known as dark energy – creating more matter causes that matter’s repelling gravity to bring about accelerating expansion).
Look at a picture of a Mobius (thanks to the repeating scales of fractal geometry, the apparently empty interior and exterior of the Mobius universe would actually be the same as the visible loop). Imagine the space/ordinary matter to be situated immediately counterclockwise (perhaps on the bottom of the loop) to the hyperspace segment and the time/dark matter portion to be immediately counterclockwise to the space/ordinary matter (time/dark matter would, moving clockwise, be next to the hyperspace segment).
The hyperspace transmissions flow directly into space/matter (all motion - “flow” and “transmissions” – are actually comparable to individual frames in a movie but are spoken of in everyday terms of motion for convenience, like saying the sun rises and sets) and are responsible for the large and unimpeded 72% increase, since the CMB was emitted, of dark energy. This flow rate of 72% also enters the time/dark matter section adjacent to hyperspace … but the loop’s twist seems to be in the time section. If we were to cut the loop lengthwise with scissors, previously varying the number of half-twists results in things such as two rings linked together or a knotted ring. So we get barriers to motion and blockages. Returning to the normal loop and twist, matters are less drastic and motion is merely slowed, resulting in a 23% flow rate.
If we lived in a non-unified universe of materialism, this is how things would remain (dark matter would have increased so today’s content would be a low 23%). On p. 179 of “The Grand Design” by Stephen Hawking and Leonard Mlodinow (Bantam Press, 2010) it’s stated “One requirement any law of nature must satisfy is that it dictates that the energy of an isolated body surrounded by empty space is positive …”
The only problem with that sentence, in an “everything is everywhere and everywhen” universe, is the word isolated. There can be no such thing as isolated in our cosmic-quantum unification. Page 179 also says “… if the energy of an isolated body were negative … there would be no reason that bodies could not appear anywhere and everywhere.” Does this mean you and I (plus all things in time and space) are a union of both positive and negative energy, able to display both separateness/solidity (isolation) as well as the potential to appear anywhere and everywhere? Dark matter, not being entirely positive, would be anywhere and everywhere as well as having decreased so today’s content would be a low 23% (which is what WMAP says is the case).
If everything is a union of positive and negative energy, every matter particle and force-carrying particle would be too. And the strings the Large Hadron Collider might detect (being the parts of particles’ Mobius loops it could see since those parts would be space/ordinary matter) might come in both positive and negative varieties. In 1928 English physicist Paul Dirac (1902-84) proposed that all negative energy states are already occupied by (then hypothetical) antiparticles (particles of antimatter). Building on this results in proposal of strings and antistrings.
My essay tells you how to travel into the future, how to return home, and how to take a trip into our past. Regarding travel beyond our start and into the past ... it can’t be denied that these paragraphs imply the possibility of humans from the distant future time-travelling to the distant past and using electronics to create this particular subuniverse's computer-generated Big Bang. An accomplishment such as this would be the supreme example of “backward causality” (effects influencing causes) promoted by Yakir Aharonov, John Cramer and others. However, realising that we live in a cosmic-quantum unification with zero-separation and recalling Isaac Newton’s inverse-square law and what it says about the force between two particles being infinite (does infinite mean 10 ^ 500, the HUGE number of universes proposed by some versions of string theory?) if the distance of separation goes to zero means there's still room for God (another bit of scientifically objectionable science fiction?) because God would be a pantheistic union of the megauniverse's material and mental parts, forming a union with humans in a cosmic unification.
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Rodney Bartlett wrote on Feb. 7, 2011 @ 02:58 GMT
According to the Community Ratings, my essay in the 2011 Essay Contest is sliding further down the ratings each day. But I'm having more luck with a science journal called General Science Journal - comments of mine inspired by the essay (which are nearly 20,000 words long and include comments about "The Nature of Time" as well as "Is Reality Digital or Analog?") were published in the Journal on Feb. 6 and may be viewed at http://gsjournal.net/ntham/bartlett.pdf
C allen wrote on Oct. 27, 2011 @ 13:53 GMT
Carlo, I was so relieved to read the truth about Time. For a long while I have understood that time is just a measurement.
Archaic thought - a bit like all the ' sun ' language.
The sun is going behind a cloud, the sun is rising etc -
Somehow we are in danger of losing common sense.
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