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Questioning the Foundations Essay Contest (2012)
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Preferred Observers in Quantum Gravity by Tanmay Vachaspati
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Author Tanmay Vachaspati wrote on Aug. 31, 2012 @ 12:06 GMT
Essay AbstractParallels are drawn between questions of after-life and questions in quantum gravity. On the basis of black hole physics and cosmology, it is argued that the classical General Relativity notion that “all observers are equal” must be qualified in a quantum theory. Various lines of reasoning suggest that only classical observers who are not trapped will play a role in the quantum theory of gravity. A possible experimental test of this hypothesis is also discussed.
Author BioTanmay Vachaspati is a theoretical physicist working at the intersections of particle physics, astrophysics, general relativity, and cosmology. He has written extensively on cosmic strings, magnetic monopoles, black holes, and cosmological magnetic fields, and has authored the monograph “Kinks and Domain Walls: an introduction to classical and quantum solitons”. He was a Rosenbaum Fellow at the Isaac Newton Institute in Cambridge, Member of the Institute for Advanced Study, Princeton, and is a Fellow of the American Physical Society. Currently he is Professor of Physics and Director of the Cosmology Initiative at Arizona State University.
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James Lee Hoover wrote on Sep. 1, 2012 @ 17:35 GMT
Tanmay,
If a black star is not a transitional phase between a collapsing star and a singularity, what is it, and how do you know the difference when anticipating the study?
Jim
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Author Tanmay Vachaspati replied on Sep. 1, 2012 @ 18:20 GMT
Jim,
Thanks. To probe a black star, we'll need something that can get up close. That is why I propose looking at mergers of candidate black holes. The gravitational wave and other particle emisson during the merger can inform us of the horizon structure.
Best,
Tanmay
Robert H McEachern wrote on Sep. 2, 2012 @ 04:36 GMT
Tanmay,
In your abstract, you state: 'it is argued that the classical General Relativity notion that "all observers are equal" must be qualified in a quantum theory'
The assumption that "all observers are equal" has been demonstrated to be untrue, even in the classical realm.
The amount of a priori knowledge that an observer has, regarding what is being observed, has a direct,...
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Tanmay,
In your abstract, you state: 'it is argued that the classical General Relativity notion that "all observers are equal" must be qualified in a quantum theory'
The assumption that "all observers are equal" has been demonstrated to be untrue, even in the classical realm.
The amount of a priori knowledge that an observer has, regarding what is being observed, has a direct, quantitative impact on the number of bits of information that the observer can successfully extract from an observation.
Since all observers do not have identical a priori information, they cannot be "equal", in the sense of being capable of extracting equal amounts of information, from an observation. Almost all modern communications systems exploit this phenomenon.
Failing to take this fact about observers into account, is the primary reason for all the supposed "weirdness" having to do with observers of quantum phenomenon.
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Anonymous replied on Sep. 2, 2012 @ 17:02 GMT
Robert,
Thanks for your comment. The observation capacity could indeed be different for different experiments and recording setups (which includes histories and amount of remaining disk space etc.). In General Relativity it is assumed that one can have the same setups located everywhere. Perhaps what you are saying is that one cannot put the same observing or recording capacity at...
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Robert,
Thanks for your comment. The observation capacity could indeed be different for different experiments and recording setups (which includes histories and amount of remaining disk space etc.). In General Relativity it is assumed that one can have the same setups located everywhere. Perhaps what you are saying is that one cannot put the same observing or recording capacity at different points in spacetime. This seems like an interesting idea to pursue!
Best,
Tanmay
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Robert H McEachern replied on Sep. 2, 2012 @ 20:04 GMT
Tanmay,
Actually, I am saying something much more subtle. For example, do you believe that the words "Relativity", "relativity", "RELATIVITY", "rElEtIvItY" are the same word? In other words, am I using the standard 26 letter English alphabet, or am I using a much larger alphabet, in which "R" is not a capital "r", but a completely different letter? If you do not know the answer, a priori,...
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Tanmay,
Actually, I am saying something much more subtle. For example, do you believe that the words "Relativity", "relativity", "RELATIVITY", "rElEtIvItY" are the same word? In other words, am I using the standard 26 letter English alphabet, or am I using a much larger alphabet, in which "R" is not a capital "r", but a completely different letter? If you do not know the answer, a priori, than you may completely misinterpret any observed message written using an "alphabet" that bears some resemblance to another that you are likely to confuse it with.
Now imagine that the letters of the "alphabet" are encoded as short bursts of several simultaneous frequency tones, too closely spaced to be resolved, and that these "symbols" are distorted prior to being received, such that the same symbol never actually is observed to appear the same.
Techniques now exist that enable an entity, with a priori knowledge of the "allowable" symbol structures, the "alphabet", to almost perfectly reconstruct such a "message", in other words, to recover its information content. An observer without such a priori knowledge cannot. Indeed, such an observer may not even recognize the signal as a message at all - it may appear to be nothing but a burst of noise.
Unbeknownst to most physicists, observational limitations, such as the Uncertainty Principle, do not apply to such knowledgable observers. If one delves into the origins of the Uncertainty Principle, deep within Fourier Analysis, one finds that the derivation of the Uncertainty Principle implicitly assumes that observers have no such a priori information to exploit. The principle is not wrong, it is simply irrelevant, for such knowledgeable observers.
While such considerations may be of little impact for astronomical observations, in which an observer has little a priori knowledge of exactly how the signals being observed were created, the same cannot be said of laboratory experiments, in which the experimenter does know a great deal about the experimental set-up. Issues like "entanglement" will almost certainly be completely misinterpreted, by any observers that fail to even appreciate the existence of such observational phenomenon, much less correctly factor it into their interpretations of experimental results.
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Member Benjamin F. Dribus wrote on Sep. 2, 2012 @ 08:22 GMT
Tanmay,
Interesting essay. Just to be sure I understand, I have a few questions.
1. You are saying that it is trapped horizons, not singularities, that imply preferred observers, correct?
2. I am trying to fit this into general ideas about covariance. In SR, covariance is a symmetry, and in GR, it is a local symmetry. Is the local symmetry still valid in your picture, since...
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Tanmay,
Interesting essay. Just to be sure I understand, I have a few questions.
1. You are saying that it is trapped horizons, not singularities, that imply preferred observers, correct?
2. I am trying to fit this into general ideas about covariance. In SR, covariance is a symmetry, and in GR, it is a local symmetry. Is the local symmetry still valid in your picture, since you are distinguishing only between asymptotic and infalling observers (who are necessarily separated)? Or is there a more radical "quantum covariance-breaking" going on?
The reason I ask is because I am interested in alternative interpretations of covariance, particularly those involving order theory. I discuss this in my essay
On the Foundational Assumptions of Modern PhysicsIn particular, covariance in the elementary setting of Minkowski space determines many of the properties of particles in QFT via representation theory, so it seems that any change in the covariance principle would be interesting in particle physics.
Take care,
Ben dribus
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Tanmay Vachaspati replied on Sep. 2, 2012 @ 17:17 GMT
Ben,
I saw your submission and will read it more carefully. In classical GR trapped surfaces lead to singularities according to the singularity theorems. So if one has an event horizon, there will also be an accompanying singularity. The real issue comes up when we include quantum evaporation because the outside observer only sees evaporation, while the inside observer sees a...
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Ben,
I saw your submission and will read it more carefully. In classical GR trapped surfaces lead to singularities according to the singularity theorems. So if one has an event horizon, there will also be an accompanying singularity. The real issue comes up when we include quantum evaporation because the outside observer only sees evaporation, while the inside observer sees a singularity.
By covariance I assume you mean invariance under coordinate transformations (diffeomorphisms). This will still hold.
Best,
Tanmay
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Saibal Mitra wrote on Sep. 2, 2012 @ 19:04 GMT
Tanmay,
You point out that the asymptotic observer can see the infalling observer frozen just before entering the event horizon for a very long time while everything gradually evaporates. Does this allow the asymptotic observer to collect enough data to (in principle) reconstruct the time evolution from the point of view of the infalling observer?
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Tanmay Vachaspati replied on Sep. 2, 2012 @ 19:25 GMT
Hello Saibal,
It isn't that there is missing data that prevents the asymptotic observer from finding out what happens to the infalling observer. The parallels between after-life and the black hole situation are extremely tight and help to understand that there are some questions that are not meaningful because they cannot be tested.
Best,
Tanmay
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Steve Dufourny replied on Sep. 2, 2012 @ 19:55 GMT
Hello to both of you,
It is relevant.
ps the singularities are all from the singularity.....
Regards
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Steve Dufourny Jedi of the Sphere replied on Sep. 22, 2012 @ 11:36 GMT
Mr Vachaspati,
Are you a buddhist ?
If the spheres of light are on the road of spherization, so it becomes relevant considering the pure optimization in its pure generality.
The death does not really exist in fact, it is logic in fact.We are inside a beautiful physical 3d sphere and its quantic and cosmological spheres. This aether , this infinite light without motion above...
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Mr Vachaspati,
Are you a buddhist ?
If the spheres of light are on the road of spherization, so it becomes relevant considering the pure optimization in its pure generality.
The death does not really exist in fact, it is logic in fact.We are inside a beautiful physical 3d sphere and its quantic and cosmological spheres. This aether , this infinite light without motion above our walls,has created a physical sphere in evolution spherization optimization improvement. So if the optimization is a reality, so....
Fascinating and wonderful are weak words.
Regards
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Sergey G Fedosin wrote on Sep. 10, 2012 @ 16:16 GMT
Dear Tanmay,
What is your opinion about Covariant theory of gravitation, in which black holes are not allowed? If to use the idea of strong gravitation at the level of particles there must be the black holes too. But nucleons are not black holes since their mass do not changed.
Sergey Fedosin
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Dear Tanmay,
What is your opinion about
Covariant theory of gravitation, in which black holes are not allowed? If to use the idea of
strong gravitation at the level of particles there must be the black holes too. But nucleons are not black holes since their mass do not changed.
Sergey Fedosin
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Author Tanmay Vachaspati replied on Sep. 11, 2012 @ 05:07 GMT
Dear Sergey,
Thank you for your comments and especially for suggesting your theory of gravitation. It is interesting that CTG passes all the current experimental constraints such as gravitational lensing, perihelion of Mercury, millisecond pulsar etc..
Yes, I agree with you, nucleons cannot be black holes because they don't evaporate. They could be extreme charged black holes for...
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Dear Sergey,
Thank you for your comments and especially for suggesting your theory of gravitation. It is interesting that CTG passes all the current experimental constraints such as gravitational lensing, perihelion of Mercury, millisecond pulsar etc..
Yes, I agree with you, nucleons cannot be black holes because they don't evaporate. They could be extreme charged black holes for them to not radiate, but that doesn't seem to be the case either.
Tanmay
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Steve Dufourny Jedi replied on Sep. 22, 2012 @ 12:14 GMT
hello thinkers,
the BH are spheres with a very important volume and mass ....it is logic that they are Black in fact. But it is not rational to say that the quantum BH exist.It is not deterministic.
Regards
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Yuri Danoyan wrote on Sep. 12, 2012 @ 01:29 GMT
Dear Tammay
In my essay http://fqxi.org/community/forum/topic/1413
i used mass of Hawking black holes as a contra to nuclons.
This is just a hypothesis.
What is your opinion?
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Author Tanmay Vachaspati replied on Sep. 12, 2012 @ 02:41 GMT
Dear Yuri,
It is really interesting that you predict black holes of mass 10^{16} gms. These are the ones that are evaporating just about now and producing a gamma ray background. Do you know the recent constraints on black hole masses? I believe the constraint might be right around 10^{16} gms but it would depend on their number density as well.
Best,
Tanmay
Yuri Danoyan wrote on Sep. 12, 2012 @ 03:07 GMT
Tammay
As you see mass of nuclon 10^40 lesser than black hole mass
it is close to
Dirac large numbers hypothesis
http://en.wikipedia.org/wiki/Dirac_large_numbers_h
ypothesis
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Member George F. R. Ellis wrote on Sep. 16, 2012 @ 15:56 GMT
Dear Tanmay
I agree with you that there are preferred observers in realistic solutions of the Einstein Field Equations. It is a significant effect.
I make the same point in a different context in a paper on the nature of time
here .
George Ellis
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Member George F. R. Ellis wrote on Sep. 16, 2012 @ 16:00 GMT
Oops:
here Hope that works
George
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Author Tanmay Vachaspati replied on Sep. 16, 2012 @ 22:46 GMT
Dear George,
Very nice to hear from you and thanks for pointing me to your article. I have taken a quick look at the paper but have to understand the EBU better. I find it very fascinating that the preferred observer hypothesis also comes up in your work in the context of the nature of time.
Best,
Tanmay
Peter Jackson wrote on Sep. 17, 2012 @ 12:00 GMT
Tanmay,
A fast moving and free thinking essay. I also found it moving, now and then, in my own direction. Have you yet considered cyclic black holes? And the re-ionization problem?possibly resolved via the 'hot bath of destructive quantum fluctuations' at the core of an em toroid AGN (SMBH) before re-ejection (astrophysical jetting).
As an astronomer I'm an observational cosmologist,...
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Tanmay,
A fast moving and free thinking essay. I also found it moving, now and then, in my own direction. Have you yet considered cyclic black holes? And the re-ionization problem?possibly resolved via the 'hot bath of destructive quantum fluctuations' at the core of an em toroid AGN (SMBH) before re-ejection (astrophysical jetting).
As an astronomer I'm an observational cosmologist, and have found much that could be interpreted in the terms you suggest, but in an eternal cycle of new iterations, at both galactic and universe scale. There is significant consistent observational evidence for such a model. Reincarnation inevitably emerges!
My own essay deals mainly with the physical mechanisms of unification, from which the cosmological model naturally emerges. I hope you can read it and comment of the logical kinetic ontology. But see also the end notes, my last years essay, and here http://vixra.org/abs/1007.0022 for work more directly relevant to yours.
Well done, and I look forward to further discussion.
Peter
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Author Tanmay Vachaspati replied on Sep. 17, 2012 @ 18:27 GMT
Dear Peter,
It's very interesting that you mention reincarnation in relation to cyclic black holes. This parallel also occurs in the literature in other contexts. For example, observers fall into black holes, go through a wormhole, and emerge in a different universe. I didn't mention this parallel in my essay because the other parallels illustrate the point I wanted to make quite well. The...
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Dear Peter,
It's very interesting that you mention reincarnation in relation to cyclic black holes. This parallel also occurs in the literature in other contexts. For example, observers fall into black holes, go through a wormhole, and emerge in a different universe. I didn't mention this parallel in my essay because the other parallels illustrate the point I wanted to make quite well. The key question of course is how do you test any of these hypotheses.
I will certainly look at your essay.
Best,
Tanmay
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Peter Jackson replied on Sep. 17, 2012 @ 18:46 GMT
Tanmay,
A strength of astronomy is that we can study the past first hand. It's then quite easy to test hypothesis and observe experiments. i.e. If we measure the accretion rates into an AGN and estimate the outflow of re-ionized matter in the (quasar) jets, we have a pretty solid experimental result when we find they match.
Then we scale up the morphology and match it to the CMBR...
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Tanmay,
A strength of astronomy is that we can study the past first hand. It's then quite easy to test hypothesis and observe experiments. i.e. If we measure the accretion rates into an AGN and estimate the outflow of re-ionized matter in the (quasar) jets, we have a pretty solid experimental result when we find they match.
Then we scale up the morphology and match it to the CMBR anisotropies, and close correlation shows scale invariance. Now we just need to live a little longer to watch the evolution of the systems. Hmmm. That's better than diving into the black hole! Any volunteers?
best wishes
Peter
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Thomas Howard Ray wrote on Sep. 17, 2012 @ 17:09 GMT
Tanmay,
Am I correct that preferred observers are not equivalent to privileged inertial frames? After all, if " ... A precise formulation of the first law should define spacetimes that are fully 'networked', i.e. they allow for a network of observers who can mutually communicate ..." a simply connected space demands only that the wave function does not collapse, and thus that it avoids the...
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Tanmay,
Am I correct that preferred observers are not equivalent to privileged inertial frames? After all, if " ... A precise formulation of the first law should define spacetimes that are fully 'networked', i.e. they allow for a network of observers who can mutually communicate ..." a simply connected space demands only that the wave function does not collapse, and thus that it avoids the singularity.
My own essay ("The Perfect First Question") agrees -- with every continuous measurement function nondegenerate near the singularity -- and also makes use of the horizon condition, as well as the asymptotic effect on measurement.
Nice essay! Best wishes in the contest.
Tom
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Author Tanmay Vachaspati replied on Sep. 17, 2012 @ 18:49 GMT
Hi Tom,
Yes, something more seems to be required from a theory of quantum gravity.
I've downloaded your essay and will give it a read. Thanks for writing.
Best,
Tanmay
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Thomas Howard Ray replied on Sep. 22, 2012 @ 10:55 GMT
I like this compact synopsis you gave in a reply to Roger Granet, "The simplest speculation is that infalling observers never fall in and stay at the horizon where they evaporate. This speculation is entirely consistent with the view of the external observer."
I think it can be made rigorous that the horizon condition at every scale plays a key role in what information we can extract from...
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I like this compact synopsis you gave in a reply to Roger Granet, "The simplest speculation is that infalling observers never fall in and stay at the horizon where they evaporate. This speculation is entirely consistent with the view of the external observer."
I think it can be made rigorous that the horizon condition at every scale plays a key role in what information we can extract from any physical phenomenon.
Tom
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John Merryman wrote on Sep. 18, 2012 @ 03:20 GMT
Tanmay,
That is an interesting conceptual connection between final stage gravitational effects and biological death. If I may riff off that somewhat, I draw similar relationships, but use a different conceptual frame.
In my entry, I make the observation that we perceive time as a sequence of events from past to future and physics re-enforces this view by treating it as a...
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Tanmay,
That is an interesting conceptual connection between final stage gravitational effects and biological death. If I may riff off that somewhat, I draw similar relationships, but use a different conceptual frame.
In my
entry, I make the observation that we perceive time as a sequence of events from past to future and physics re-enforces this view by treating it as a measurement issue, but the underlaying physical process is the changing configuration of what exists, turns future potential to present actual, then past residual. Not the earth traveling a narrative dimension from yesterday to tomorrow, but tomorrow becoming yesterday because the earth rotates. Duration then is not a dimension transcending the present, but is the state of the present between events.
So in this view, while the present goes from past to future, alternatively, events go future to past. Now think how this applies to life; The unit of time that is the individual life starts in the future, exists in the present and then dying, fades into the past. Meanwhile the species has moved onto the next generation, like the hands of the clock move onto the next unit of time.
Consider this in terms of a factory: The product moves from start to finish, while the production process points the other direction; Consuming raw materials and expelling finished product.
Our minds work like that as well. Consuming information and creating thought, which then are replaced by the next and fade into the past.
Our bodies as well are processes of generations of cells that form, go about their functions and then are shed, as the body lives.
In very basic terms we have energy manifesting information and information defining energy. In fact our bodies consist of two integrated systems to deal with both side of this coin. The central nervous system and the senses process information, while the circulatory, digestive and respiratory systems process energy. both integrated to manipulate our limbs and actions to gather more energy and information.
Yet energy is ultimately conserved. It is the state of the present, that which the energy is activating. So in order to create new information, old information is erased. You really can't have your cake and eat it too. Time then emerges from this creation and dissolution of energy.
So how does this tie in with your relating gravity to death? The past is that which is ordered, while the future is where the energy goes. Once structure has reached its apex of structural potential, the only path left is decline. Entropy only applies to such closed sets. Yet as structure looses energy, the remaining structure becomes ever more dense. As heat and light radiates away, what is left is crunched down to ever more solid structure.
Meanwhile that light and radiation expands out to create, expand and grow new structure. So the radiant energy is the arrow of time that points from past to future, as the gravitational density of mass is what coalesces out of future possibility and becomes residually harder. Until it too falls into that final gravitational vortex and is shot out as jets of cosmic rays, for billions of lightyears. So the cycle starts over again.
I do see math as simply modeling reality, rather than the basis for it. (It's information.) So black holes and singularities are not real, but models of this infalling process. So what is gravity? When mass turns to radiation, it creates pressure. Just think of the shock wave of an atomic bomb. So what happens when energy fuses into mass? Wouldn't it create a vacuum? Since nature is not fond of vacuums and fills them in, the result is gravity. Consider they haven't found dark matter, but there is lots of unexplained cosmic rays throughout the galaxy. Could they, in the near absolute zero of interstellar space, be coalescing into gases? Which then continue to coalesce into mass, which then is getting ever more dense, thus constantly creating more vacuum? It would explain why no gravity waves have been detected, because it is all around us, as the radiation being created by fusion.
Since the absolute is basis, not apex, a spiritual absolute would be the essence from which we rise and return, not an ideal from which we fell and seek to climb back up. That essence simply pushes the reset button fairly regularly and the cycle of gathering information and structure starts over again.
I could continue, but I was just trying to connect gravity, the past and death.
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John Merryman replied on Sep. 18, 2012 @ 03:27 GMT
Corrections:
Time then emerges from this creation and dissolution of information.
as the gravitational density of mass is what coalesces out of future possibility and becomes residually harder.(Being the arrow of time that points from future to past.)
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Author Tanmay Vachaspati replied on Sep. 18, 2012 @ 06:18 GMT
Hi John,
Thanks for the note. I enjoyed your poetic phrases (arc of time) and the example of the blurring photograph with greater information.
Best,
Tanmay
John Merryman replied on Sep. 18, 2012 @ 10:28 GMT
Tanmay,
Thank you.
Obviously it's just a seed of an idea, but I think and as this contest is evidence, physics has peaked out with where the current model can logically go. It's doubtful future generations of physicists will simply worship at the alter of a model that leaves little more to test, now that the search for the Higgs has proven to be a climb up a lonely mountain and not...
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Tanmay,
Thank you.
Obviously it's just a seed of an idea, but I think and as this contest is evidence, physics has peaked out with where the current model can logically go. It's doubtful future generations of physicists will simply worship at the alter of a model that leaves little more to test, now that the search for the Higgs has proven to be a climb up a lonely mountain and not a stairway to heaven of ever more exotic particles, strings, dimensions, etc.
So long as the structure can absorb new energy, the future is a continuation of the past, but when it can no longer grow, then the future becomes a reaction to the past.
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Author Tanmay Vachaspati replied on Sep. 18, 2012 @ 13:49 GMT
Hi John,
Wouldn't you agree it is too early to say if the LHC is/is not a "stairway to heaven"?
Tanmay
John Merryman replied on Sep. 18, 2012 @ 16:04 GMT
Tanmay,
I don't qualify as a particle physicist, so I tend to go by what I read. Which on that subject tends to be Peter Woit's Not Even Wrong blog.
I do think some of the deeper conceptual foundations became set in stone before they really had could be investigated thoroughly.
Here is an interesting interview with Carver Mead.
There are various entries in this...
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Tanmay,
I don't qualify as a particle physicist, so I tend to go by what I read. Which on that subject tends to be Peter Woit's Not Even Wrong blog.
I do think some of the deeper conceptual foundations became set in stone before they really had could be investigated thoroughly.
Here is an interesting interview with
Carver Mead.
There are various entries in this contest which make some interesting observations about the evolution of the current model. I think
Robert McEachern makes an interesting argument about how modern information theory has evolved differently than the foundational math on which theoretical physics is based. It provides an argument for the difference between theory and application in information, that Carver Mead makes for the physical side of the equation.
As example of my own skepticism is a recent discussion I was having with
Daryl Janzen, over universal expansion. To quote relevant comments from both issues;
"Daryl,
What is the source of that "rate of propagation through space as a constant value," if it isn't space? The most basic measure of cosmic distances is how far light travels in a year. So you say "space expands." Therefore it's not that expanding space. What determines how you move that marker down that elastic band, that defines constant? If it is "constant," then it must mean it's stable. What is that stable frame????"
"Daryl,
" Every galaxy stays at the same coordinates while the space between them all expands."
Galaxies are not inert point particles. Relativity specifically makes the argument that gravity contracts space, such that galaxies amount to space wells. So, yes, the space between galaxies is expanding, but then it would seem to be balanced by the effect of falling into galaxies. As an analogy, think of walking up the down escalator. It only seems the floors keep moving apart as you walk from one to the other, but the space of the steps is falling into the floor from which you started and keeps increasing in front of you. The resulting balance between the overall expansion and contraction results in overall flat space, as measurements from COBE and WMAP seem to show."
I have to say I didn't set out, 35 years ago, to question physics, but the more I looked into it, the more it seemed beset by mortal humans, doing what they do best, improvising in the face of the unknown, then canonizing these early efforts in order to continue. Sometimes we have to consider current efforts are coming to naught and it might be best to reset and examine the foundations. While I certainly don't expect those who have devoted their careers to the current situation to take those outside the field seriously, I'm one of those who see the emperor as naked, fat and unhealthy.
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Hoang cao Hai wrote on Sep. 19, 2012 @ 13:45 GMT
Dear
Very interesting to see your essay.
Perhaps all of us are convinced that: the choice of yourself is right!That of course is reasonable.
So may be we should work together to let's the consider clearly defined for the basis foundations theoretical as the most challenging with intellectual of all of us.
Why we do not try to start with a real challenge is very close...
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Dear
Very interesting to see your essay.
Perhaps all of us are convinced that: the choice of yourself is right!That of course is reasonable.
So may be we should work together to let's the consider clearly defined for the basis foundations theoretical as the most challenging with intellectual of all of us.
Why we do not try to start with a real challenge is very close and are the focus of interest of the human science: it is a matter of mass and grain Higg boson of the standard model.
Knowledge and belief reasoning of you will to express an opinion on this matter:
You have think that: the Mass is the expression of the impact force to material - so no impact force, we do not feel the Higg boson - similar to the case of no weight outside the Earth's atmosphere.
Does there need to be a particle with mass for everything have volume? If so, then why the mass of everything change when moving from the Earth to the Moon? Higg boson is lighter by the Moon's gravity is weaker than of Earth?
The LHC particle accelerator used to "Smashed" until "Ejected" Higg boson, but why only when the "Smashed" can see it,and when off then not see it ?
Can be "locked" Higg particles? so when "released" if we do not force to it by any the Force, how to know that it is "out" or not?
You are should be boldly to give a definition of weight that you think is right for us to enjoy, or oppose my opinion.
Because in the process of research, the value of "failure" or "success" is the similar with science. The purpose of a correct theory be must is without any a wrong point ?
Glad to see from you comments soon,because still have too many of the same problems.
Regard !
Hải.Caohoàng of THE INCORRECT ASSUMPTIONS AND A CORRECT THEORY
August 23, 2012 - 11:51 GMT on this essay contest.
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Author Tanmay Vachaspati replied on Sep. 20, 2012 @ 01:35 GMT
Thanks for your comments, Hoang.
The Higgs, as you well know, is "seen" indirectly due to its decays into photons and other particles. The basic interactions involve left- and right-handed particles which only makes sense if the particles are fundamentally massless. That is why the Higgs is necessary to give them a mass.
Best,
Tanmay
Sridattadev wrote on Sep. 19, 2012 @ 18:32 GMT
Dear Tanmay,
I hope you will find the essay on true nature of our self (singularity) resonate with your ideas. Infact we will all have to go through a black hole (death of the ego) to attain the singularity of our true self (immortality or nirvana or enlightenment).
Conscience is the cosmological constant.
Love,
Sridattadev.
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Dear Tanmay,
I hope you will find the essay on true nature of our self (singularity) resonate with your ideas. Infact we will all have to go through a black hole (death of the ego) to attain the singularity of our true self (immortality or nirvana or enlightenment).
Conscience is the cosmological constant.Love,
Sridattadev.
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Author Tanmay Vachaspati replied on Sep. 20, 2012 @ 01:36 GMT
Dear Sridattadev,
Thank you for your kind words.
Tanmay
Avtar Singh wrote on Sep. 19, 2012 @ 22:57 GMT
Dear Tanmay:
I enjoyed reading your well-written and intuitive essay describing the observer paradox in GR and QM as it relates to black holes.
Then, you state that – “…For the purposes of a physical theory, it is sufficient to describe gravitational collapse from the external point of view, just as we are able to describe our physical world regardless of Heaven or Hell. The...
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Dear Tanmay:
I enjoyed reading your well-written and intuitive essay describing the observer paradox in GR and QM as it relates to black holes.
Then, you state that – “…For the purposes of a physical theory, it is sufficient to describe gravitational collapse from the external point of view, just as we are able to describe our physical world regardless of Heaven or Hell. The infalling observer’s description is irrelevant for a physical theory; the asymptotic observer is a preferred observer.“
My paper -“
From Absurd to Elegant Universe” provides answers to the questions you raise and forwards a mathematical model of the universe that resolves many of the QM and GR related paradoxes – dark energy, dark matter, black hole and cosmic horizons, observer paradox, bubble or baby universes, fundamental particles/strings etc. These are shown to be mere artifacts of the missing physics (from the current theories QM and GR ) of spontaneous particle decay or evaporation that also simulates the black hole evaporation. It also demonstrates that the observed classical, quantum, and universe behavior can be explained via physical theory independent of the observer’s description.
The holistic model also successfully predicts the observed data at all scales from below Planck scale to beyond cosmological scales. The holistic model also explains the inner workings of QM and eliminates its paradoxes and inconsistencies with relativity. It also vindicates that time is not a fundamental entity since the observed universe and galactic expansion can be predicted without any explicit consideration of a cosmic time.
I would greatly appreciate your comments on my paper. You can contact me at avsingh@alum.mit.edu.
Best Regards
Avtar Singh
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Author Tanmay Vachaspati replied on Sep. 20, 2012 @ 01:40 GMT
Dear Avtar,
I look forward to reading your essay.
Best,
Tanmay
Roger Granet wrote on Sep. 21, 2012 @ 04:44 GMT
Dr. Vachaspati,
Hi. I think your essay was good because it considered how different observers would view the same thing, a point that I don't see discussed much. Since I'm not a physicist, I can't say I totally understood your essay, but my two comments are:
1. If I understood it correctly, it sounded like you're saying that in developing our theories, we should view things...
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Dr. Vachaspati,
Hi. I think your essay was good because it considered how different observers would view the same thing, a point that I don't see discussed much. Since I'm not a physicist, I can't say I totally understood your essay, but my two comments are:
1. If I understood it correctly, it sounded like you're saying that in developing our theories, we should view things from a particular, preferred, observer's reference frame, like the asymptotic observer in the black hole example. While this sounds reasonable, it would also seem worthwhile to try and develop a theory of how the non-preferred observer (e.g., the infalling observer in the black hole example) would see phenomena. The reason for this being that while the non-preferred, infalling, observer's theory may not be useful to us in describing a particular phenomena like a black hole, maybe we are the non-preferred observers in other situations and may find the infalling observer's view of things relevant to the new situation?
2. In the last FQXi essay, I tried to point out how two different observers might view an infinite set of identical balls expanding out in all directions. An observer with the same size scale as the balls and that is inside the set (probably the preferred observer) would see it as a discrete space made of finite sized units. A hypothetical, infinitely-sized observer (probably the non-preferred observer) outside the set would not be able to see the edges of the balls and would see the set as containing a continuous space. By thinking how each observer might view the set, we can apply these different views to other situations where we may not be the preferred observer.
More on this is at:
https://sites.google.com/site/ralphthewebsite/filecabinet
/infinite-sets-ii
Anyways, nice essay! Thanks.
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Author Tanmay Vachaspati replied on Sep. 21, 2012 @ 14:56 GMT
Dear Roger,
Thank you for raising a very important point. A physical theory needs to be self-consistent (no self-contradictions) and to have closure (not influenced by agencies that lie outside the system). This is true of the theory as described from the outside point of view. We are free to speculate on what the infalling observer will see -- any description is as good as any other --...
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Dear Roger,
Thank you for raising a very important point. A physical theory needs to be self-consistent (no self-contradictions) and to have closure (not influenced by agencies that lie outside the system). This is true of the theory as described from the outside point of view. We are free to speculate on what the infalling observer will see -- any description is as good as any other -- because there is no way to test the speculation. The simplest speculation is that infalling observers never fall in and stay at the horizon where they evaporate. This speculation is entirely consistent with the view of the external observer.
It would be fun to tie your view with that of preferred observers. It might also be fun to try and draw a picture of what the view would look like.
Thanks again for writing.
Best,
Tanmay
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Pentcho Valev wrote on Sep. 21, 2012 @ 06:50 GMT
Dear Dr. Vachaspati,
Let me call your attention, very politely (so that you could be so kind as not to delete my comment), to an observer who measures VARIABLE speed of the light waves:
Professor Carl Mungan: "Consider the case where the observer moves toward the source. In this case, the observer is rushing head-long into the wavefronts, so that we expect v'>v. In fact, the wave...
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Dear Dr. Vachaspati,
Let me call your attention, very politely (so that you could be so kind as not to delete my comment), to an observer who measures VARIABLE speed of the light waves:
Professor Carl Mungan: "Consider the case where the observer moves toward the source. In this case, the observer is rushing head-long into the wavefronts, so that we expect v'>v. In fact, the wave speed is simply increased by the observer speed, as we can see by jumping into the observer's frame of reference. Thus, v'=v+v_o=v(1+v_o/v). Finally, the frequency must increase by exactly the same factor as the wave speed increased, in order to ensure that L'=L -> v'/f'=v/f. Putting everything together, we thus have: OBSERVER MOVING TOWARD SOURCE: L'=L; f'=f(1+v_o/v); v'=v+v_o."
Professor Sidney Redner: "The Doppler effect is the shift in frequency of a wave that occurs when the wave source, or the detector of the wave, is moving. Applications of the Doppler effect range from medical tests using ultrasound to radar detectors and astronomy (with electromagnetic waves). (...) We will focus on sound waves in describing the Doppler effect, but it works for other waves too. (...) Let's say you, the observer, now move toward the source with velocity vO. You encounter more waves per unit time than you did before. Relative to you, the waves travel at a higher speed: v'=v+vO. The frequency of the waves you detect is higher, and is given by: f'=v'/(lambda)=(v+vO)/(lambda)."
Does the observer moving towards the source deserve special mention, dear Dr. Vachaspati? Is special relativity in danger?
Sincerely yours, Pentcho Valev
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Author Tanmay Vachaspati replied on Sep. 21, 2012 @ 14:58 GMT
Hi Pentcho,
I don't see why special relativity should be in danger. It seems to work very well in accelerators where particles move very close to the speed of light.
Bye,
Tanmay
Pentcho Valev replied on Sep. 22, 2012 @ 09:28 GMT
The fact that the moving observer measures VARIABLE speed of light obviously deserves no mention at all. Thank you, dear Dr. Vachaspati.
Pentcho Valev
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Sergey G Fedosin wrote on Oct. 2, 2012 @ 08:27 GMT
After studying about 250 essays in this contest, I realize now, how can I assess the level of each submitted work. Accordingly, I rated some essays, including yours.
Cood luck.
Sergey Fedosin
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Author Tanmay Vachaspati replied on Oct. 2, 2012 @ 14:35 GMT
It is a lot of hard work. I am still going through the list. Thanks for reading and rating my essay.
Best,
Tanmay
Georgina Parry wrote on Oct. 3, 2012 @ 23:32 GMT
Dear Tanmay Vachaspati,
your essay is written very clearly in accessible language. I really appreciate that. I am a little surprised that you have chosen this particular subject. Especially having looked at the broad scope of your biography. The heaven and hell analogy was a little strange for me. Though I do understand that you are talking about personal experience that can not be corroborated by any other. Observer experience of speculated after life and/or black hole experience seem too "other worldly/abstract" to be -basic- physical assumptions. Having said that , of the "technical" essays in the contest, yours is more readable than many others. It is therefore enjoyable,interesting, and thought provoking rather than a difficult unpleasant chore. Well done, Good luck Georgina : )
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Author Tanmay Vachaspati replied on Oct. 4, 2012 @ 00:41 GMT
Dear Georgina,
I am glad you enjoyed my essay. The heaven-hell analogy is exactly as you said -- personal experiences that cannot be corroborated by any other.
Best of luck to you too!
Tanmay
Sergey G Fedosin wrote on Oct. 4, 2012 @ 05:38 GMT
If you do not understand why your rating dropped down. As I found ratings in the contest are calculated in the next way. Suppose your rating is
and
was the quantity of people which gave you ratings. Then you have
of points. After it anyone give you
of points so you have
of points and
is the common quantity of the people which gave you ratings. At the same time you will have
of points. From here, if you want to be R2 > R1 there must be:
or
or
In other words if you want to increase rating of anyone you must give him more points
then the participant`s rating
was at the moment you rated him. From here it is seen that in the contest are special rules for ratings. And from here there are misunderstanding of some participants what is happened with their ratings. Moreover since community ratings are hided some participants do not sure how increase ratings of others and gives them maximum 10 points. But in the case the scale from 1 to 10 of points do not work, and some essays are overestimated and some essays are drop down. In my opinion it is a bad problem with this Contest rating process. I hope the FQXI community will change the rating process.
Sergey Fedosin
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Daryl Janzen wrote on Oct. 4, 2012 @ 22:14 GMT
Dear Tanmay:
Thank you for your essay. I'm sorry that I missed it before, but I'm really glad now that I've read it. I agree with you about black stars, and I think that taking accurate and consistent account of descriptions according to preferred observers will provide the correct path to a quantum theory of gravity. As such, I particularly liked and agreed with your paragraph that begins...
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Dear Tanmay:
Thank you for your essay. I'm sorry that I missed it before, but I'm really glad now that I've read it. I agree with you about black stars, and I think that taking accurate and consistent account of descriptions according to preferred observers will provide the correct path to a quantum theory of gravity. As such, I particularly liked and agreed with your paragraph that begins ``Just as Newton's first law defines inertial frames...''. I think the analogy to Newton's first and second laws is appropriate. Special relativity theory does retain the special status of *all* inertial observers that was given in Newton's theory, which, together with the light postulate, leads to such effects as the relativity of simultaneity and block space-time. In contrast, I think that for reasons of causal coherence, similar to the ``networking'' you've described in your essay, the right ``first law'' for quantum gravity should distinguish a particular set of inertial observers as preferred, whose clocks all measure a Cosmic time. In
my essay, I've described how special relativity would need to be re-interpreted within this context, but the interpretation of the theory that I've drawn there should extend to general solutions in a way that is, I think, entirely relevant to your argument here. I sincerely hope you'll read my essay, because there's so much that I'd like to discuss with you.
In hopes that you do, I'll add two paragraphs to briefly describe my thoughts. Given a three-dimensional universe that endures with absolute cosmic time (as relativity theory can be interpreted to describe in many solutions), a black hole cannot be said to be created through gravitational collapse through the Schwarzschild (coordinate) singularity, r_Sch, in finite cosmic time. In the Schwarzschild solution, an observer at r=infty should measure cosmic time there, and for that reason I think it's already wrong to conclude that particles can cross r_Sch in finite cosmic time. Now, while I think slices of constant Schwarzschild t should not be constant cosmic time slices, but that t should only describe cosmic time at r=infty (my reason should hopefully become clear below), thinking of them as such proves quite illustrative. Please consider an Eddington-Finkelstein diagram, interpreted so that slices of constant *Schwarzschild* t describe the universe outside a spherical star at values of constant cosmic time. This means that an event at r_1>r_Sch is said to occur ``simultaneously'' with an event at r_2>r_Sch if they both lie on the slice t=const.---and this, even though they are not ``synchronous'' in Eddington-Finkelstein coordinates; i.e., they don't occur at the same value of the timelike coordinate in this frame. Commonly, one used to interpret the infall of a body in this frame in the following way: one observer leaves another at some r_O>r_Sch and heads towards the black hole while the other remains fixed at r_O. At some finite time the infalling observer crosses r_Sch, and eventually reaches the singularity at r=0, while the outside observer remains forever at r_O. This description assumes that in this frame everything ``happens'' along the horizontal ``synchronous'' slices in the diagram. But if Schwarzschild t is interpreted as the absolute cosmic time everywhere, the description is very different: as the infalling observer approaches r_Sch, both he and his friend evolve coherently along slices of Schwarzschild t, so that eventually, when he reaches r_Sch, his friend is not ``beside'' him, at the same value of Eddington-Finkelstein time, but is himself at t=infty. Whatever happens after that, happens after the end of t.
I think there is an analogous consideration to be made in the case of de Sitter space. Please consider the two figures I've attached below, which illustrate statical coordinates of de Sitter space, from r=-r_h to r=+r_h (where r_h is the horizon radius; the radial coordinate r is actually imaginary beyond r_h), on a two-dimensional slice of de Sitter space in 3D Minkowski space. Slices of constant t are drawn in black and worldlines of constant r are drawn in red (please excuse my re-use of coordinates r and t in the statical line-element of de Sitter space). There are many different cosmological coordinations of de Sitter space that one may choose from, such as the line-element of the Steady State theory or the three-sphere that contracts to a finite radius and then expands, as I've mentioned in my essay---but the statical coordinates do not describe a cosmological model. Even so, a clock at the geodesic at r=0 in these coordinates does measure cosmic time. So let's consider the universe (the enduring three-sphere) that's described by the coherent bundle of similar geodesics around the hyperboloid: from the perspective of the observer at r=0 who uses statical de Sitter coordinates (r and t) to describe local space-time, other comoving cosmological geodesics *enter* the patch described by those coordinates at some *finite negative cosmic time* (i.e., finite negative T in the line-element given in Eq. (3) in my essay) at t=-infty. These geodesics move inwards along r until T=0, and then move outwards, eventually crossing the null line t=+infty at *finite positive cosmic time*. When this happens, they cross a causal horizon, and will never again be able to communicate with the observer at r=0. Even so, there is a very important point:---no timelike worldline that intersects r less than r_h at any t can ever cross the coordinate singularity r=r_h which lies at the intersection of two null lines connected to the central observer at T=-infty and T=+infty. It's inconsistent to interpret particles that cross the cosmological event horizon in this solution as crossing r=r_h, and moving out along r faster than the speed of light. In fact, the coordinate r loses all meaning at r=r_h, where it becomes imaginary.
For similar reasons, I think it's got to be wrong to describe the r-coordinate in Schwarzschild's solution as continuously real across the coordinate singularity, r_Sch, and thus describe that as an event horizon. Analogous to the statical de Sitter line-element, Schwarzschild's solution is given with respect to the asymptotic observer, who measures cosmic time, and who can never see anything that exists beyond r=r_Sch. And just as in the case of de Sitter space, I think it's wrong to say that any timelike observer can move in the r direction and actually reach r_Sch.
By the way, someone went through the top-rated essays while I was writing this and gave us all scores of 1. I've just given your essay a deserving rating in hopes of combatting that. I hope you'll consider rating my essay too, if you manage to read it in time. I haven't discussed its content here, but something of a consequence of the description of time I've argued for in the third section.
Best of luck,
Daryl
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Daryl Janzen replied on Oct. 4, 2012 @ 22:55 GMT
Sorry. Here are the figures I meant to attach.
attachments:
dS_statical1.pdf,
dS_statical2.pdf
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Author Tanmay Vachaspati replied on Oct. 5, 2012 @ 03:44 GMT
Dear Daryl,
Thanks a lot for your post. At first read it looks like we agree but I'll go over your arguments and especially your essay more carefully.
Best,
Tanmay
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