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Blogger Mark Wyman wrote on Aug. 1, 2010 @ 21:07 GMT
http://toonstoonstoons.net/category/cartoon/
Scientific researchers, especially younger ones dreaming of glory and fame, are generally averse to setting boundaries and claiming absolute limits. This stems both from a hopefulness that Nature will be kind enough to give us plenty of new secrets to unravel in the future as well as an anxiety about ending up later as the villain in a just-so story about how the “establishment” naively criticized a new theory when it first appeared. In light of this, it’s always notable when researchers find a new way of stating just how limiting the laws we know are. A very fine example of this kind of work appeared recently on the arXiv, in a paper by Gia Dvali and Cesar Gomez, Self-Completeness of Einstein Gravity.

This paper rains on the parade of those who hope against hope that there will be a fundamental theory of gravity with a regime of validity that pierces the Planck length. The Planck length is the smallest length scale presently contemplated in all of Physics: it is the length scale where gravity becomes as strong as the other fundamental forces. General relativity (GR) predicts that any experiment with enough energy to probe the Planck length must necessarily form a black hole in the process, thwarting the ability of the experiment to send out any results describing what happened on shorter length scales. What we’re not sure of is whether GR is right about this.

Dvali and Gomez’s paper is a subtle and powerful argument that GR is correct on this point: they pull together a variety of lines of reasoning to this effect, but the central claim and most powerful claim is that there is, in effect, _no_ _difference_ between the super-high energy physics inside the Planck length and well-known black hole physics. The idea is this: the way gravity works is that it wraps a black hole horizon around any region of space that reaches Planckian energy-densities. This black hole is a kind of buffer that absorbs the huge energy density, converting it into the relatively slower moving physics of black holes, where the energy will leak out later in the form of Hawking radiation. In other words: the Planck length also sets a minimum time scale in nature, a Planck time, faster than which nothing can occur. If an event is set to occur more quickly than this time, it get bounced or reflected by gravity into a black hole that flips that fast moving event into a slower-moving black hole horizon. The bigger the energy, the bigger the resulting black hole, and hence the _longer_ it takes for the energy to escape as Hawking radiation.

If true, this means that the real locus of our hope for novel physics is the Planck length itself. A black hole that just barely has enough energy to form evaporates most quickly. If we could see such a thing happen, we could get a window into the ultimate energy scale of physics. However, such a black hole is far beyond the scope of our most powerful Earth-based accelerators: it is fifteen _orders_ _of_ _magnitude_ smaller than the length scales that the Large Hadron Collider’s record-breaking collisions will probe, for instance. (Ie, to get to the Planck length, you’d need an accelerator 1,000,000,000,000,000 times more powerful than the LHC!). So it remains a big open question as to whether Dvali and Gomez’s ideas will ever be tested. In the meantime, we will have plenty of opportunity to explore whether there are any sneaky ways to get around their arguments; and you can count on it that many researchers are already looking to do just that, if they can!

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John Merryman wrote on Aug. 1, 2010 @ 23:49 GMT
Uh, what does this say about Inflation Theory? Wouldn't the universe collapse back into the singularity and not expand out at many times the speed of light, to a size much larger than the visible universe?

"The idea is this: the way gravity works is that it wraps a black hole horizon around any region of space that reaches Planckian energy-densities."

Surely there must have been "Planckian energy-densities" in that first moment after the singularity popped into existence!

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The Lightbringer replied on Aug. 7, 2010 @ 19:55 GMT
Inflation theory only works because the self represents, forms, and experiences a comprehensive approximation of the totality of experience by combining unconscious and conscious experience. Inflation theory relates, accordingly, to our growth and development, yet it is garbage all the same.

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Lawrence B. Crowell wrote on Aug. 2, 2010 @ 00:21 GMT
I have not read the Dvali Gomez paper yet. However, the UV/IR correspondence does pretty clearly indicate that the Planck scale is an hard cut off with measurable physics.

Chers LC

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T H Ray replied on Aug. 2, 2010 @ 11:54 GMT
I agree, Lawrence. Einstein (classical) gravity and string theory are non-separable in my own model as well, in that the parabolic projections of n-dimension kissing spheres bounding the hyperbolic space of string theory make Einstein's "finite but unbounded" continuous spacetime manifold continuous (via string energy) to higher dimensions. (It would be infinitely continuous, but for my result that the 4 dimension horizon is identical to the 10 dimension limit, which implies measurability.)

Tom

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Jason Wolfe wrote on Aug. 2, 2010 @ 04:25 GMT
John,

You do raise an interesting point. In the first few microseconds of the Big Bang, why didn't the universe just become a Black Hole?

The W and Z particles of the weak force are a hundred times more massive than the neutron that emits it. Of course, the W particle doesn't last very long, about 10^-25 seconds. This puts energy conservation on shaky grounds. In contrast, I guess the Big Bang is thought to occur when a singularity pops into existence, once in a ridiculously long time.

Events like these really do undermine conservation of energy.

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Lawrence B. Crowell wrote on Aug. 2, 2010 @ 15:50 GMT
One point of using sphere packing to look at these problems is these structures are quantum error correction codes. The set of transformations are modular, or given by modular functions. This means quantum gravity might modular, quantum information is conserved by the n-folding of modular functions. For the E_8 group and the higher Leech lattice system, which has a triality on 3 copies of E_8, the underlying functions are Jacobi θ-functions of the form. These functions are solutions of the heat equation, or constitute the heat kernel. These functions exist on the (z,t) space and for t - -> it are of the form

Θ(z, t) = 1 + 2sum_{n=1}^∞ e^{-πin^2t}cos(2πnz)

which solve the equation

∂θ/∂t = (1/4πi)∂^2θ/∂z^2.

This is the heat equation for t, where ∂^2θ/∂z^2 forms the Laplacian of the heat kernel. For t - -> it is a form of the Schrodinger equation. So there is an underlying unitarity to the modular system. This is a unitarity on the string world sheet of two dimensions z parameterized by t, which is in complex variables the Riemann sphere. The parameterization of string world sheets is a cylinder, and if we include two caps to close the end, each cap is contractible to a point. The string world sheet is stereographically mapped to the Riemann sphere, and this is a parameterization of Riemann sheets.

If this is returned to a heat equation form, the Laplacian on the complex plane, with z = (z1,z2) has the form

Δ = ∂^2/∂z^2 = ∂^2/∂z1^2 - ∂^2/∂z2^2

and the time variable plays the role of a conformal factor which maps the two dimensional Riemannian space (Riemann sphere) from one to another with a different radius. So this is a Ricci flow on the string world sheet. The Laplacian describes string dynamics with the Lagrangian

L = ½ sum_k(∂X/∂z_k)(∂X/∂z_k) + . . .

and the Ricci flow determines the domain of the scale length for the string. This parameter then extends from the Planck length, the cut off, to the horizon length, or sqrt(horizon area). That horizon could be the horizon of a black hole the string is interacting with or the entire spacetime cosmology. So these are the UV and IR cutoffs in the scaling of the system, which are the “caps” mentioned above. These caps are balls, in the space of possible string world sheets they are 3-balls, with 2-sphere boundaries. These spheres then contain information about scaling bounds.

Cheers LC

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John Merryman replied on Aug. 3, 2010 @ 00:01 GMT
Lawrence,

With all the extra dimensions and complex math, wouldn't it be far easier to diagram a process by which what is falling into black holes emerges as quantum fluctuation across space? This would be a far simpler explanation for redshift and cosmic background radiation, that that Big Bang/Inflation monstrosity.

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Lawrence B. Crowell replied on Aug. 3, 2010 @ 01:31 GMT
L. Susskind has done these cosmology lectures, and I can only suggest you watch these. Big bang and inflationary cosmology is pretty well established. The basic big bang cosmology is benchmarked by a range of observations. Inflation does not explain everything at this point, It does solve a range of problems, in particular inflation solves the flatness problem. Aspects of that prediction have been born out with the WMAP data on CMB anisotropy. Inflation is an approximatio to something else, for it has to be narrowly constrained to within 63 e-folds and the nature of the scalar field has to be "crafted," and so forth. It is a bit like the same situation with the standard EW model in particle physics.

Cheers LC

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John Merryman replied on Aug. 3, 2010 @ 02:22 GMT
Lawrence,

I'm sure block time and many worlds are equally well established.

One of those range of observations they missed by a mile was the rate of expansion(minor point), so now we are supposed to accept dark energy.

Inflation was a prior fudge factor. That's why it has to be constrained, "crafted," and so forth. Why did it bother to slow down to the rate of expansion which presumably exists now? There surely isn't enough gravitational drag to do it, especially in light of all the "dark energy" presumably still pushing things apart.

While the effect assigned to dark energy was completely out of the blue for Big Bang theory, it apparently is a close match for the Cosmological Constant, which Einstein originally inserted to balance the effect of gravity and maintain a stable universe. So what prevents any discussion of the remote possibility that that is exactly what it does?

Inflation might solve the flatness problem, but at the expense of creating far more problems. For most people, the obvious solution is to go back to the start and figure out what is the underlaying problem, but obviously cosmologists are much smarter than other people, so they could never be wrong in the first place and this would just be a waste of time.

The cosmological background radiation is extremely smooth and since the universe began with an enormous explosion, it must have been some initial shock wave which caused this smoothness. What if it's just vacuum fluctuation and there is a transition level above which it isn't stable and collapses back into the vacuum? Essentially the vacuum expands and collapses. On top of explaining the redshift and CMBR, it also explains gravity.

Oh. no! I just don't understand. I'm to uneducated in the finer points of cosmology. Fact is Lawrence, you don't understand dark energy, or Inflation either, because no one else does. They are fudge factors that no one has effectively constrained or "crafted."

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Lawrence B. Crowell wrote on Aug. 3, 2010 @ 14:35 GMT
This approach with Jacobi θ-functions segues into sphere packing. The symmetries of the θ-functions derive a finite element subset of the Heisenberg group. The Hesenberg group emerges from the stabilizer of lightlike geodesics in E^n (Einstein spacetime). The construction of light cones is then possible from the identification with poles on S^n. The null condition on light rays is defined by a projective geometry or equivalently by a stabilizer of O(2,n) (elements g such that gx = x) that is

R\times SL(2,R) x O(n-2)|X Heis(2n-3) ( |X = semidirect product)

where Heis(2n-3) is the Heisenberg group of 2n – 3 dimensions. In AdS_{n+1} with two timelike directions the projective geometry is then “mod 2-planes = P,” just as regular projective space is R^n/(x ~ λx) and the lightcones or null directions are defined by O(2,n)/P. Now if we include the positive and negative sequences on S^n, this is related to the space PT^+ and PT^- in twistor theory.

The discrete structure of E_8 and the Leech lattice Λ_{24} have Jacobi θ-function realizations, which are discussed at length in Conway & Sloane. The Jacobi θ-functions also obey a heat equation, and the heat kernel is a Fredholm alternative. This then should lead to a gauge-theoretic like system for gravity within a geometric quantization.

Cheers LC

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Don Limuti (www.zenophysics.com) wrote on Aug. 4, 2010 @ 02:50 GMT
John M. I like your concept: "Essentially the vacuum expands and collapses. On top of explaining the redshift and CMBR, it also explains gravity."

Lawrence C. likes to quote from the math Bible, which has many adherents. I personally like math (and Lawrence) but always keep in mind a mathematician's allegiance is to logic that follows from axioms. This may or may not correspond to physical reality but in either case the logic is perfect.

Dvali and Gomez's ideas about the Planck Length have merit. They should also show that the Planck Mass is the limiting mass at the Planck Length.

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Steve Dufourny wrote on Aug. 4, 2010 @ 11:26 GMT
Dear Don ,interesting could you develop please,why that explains gravity???

Essentially the vacuum expands and collapses. On top of explaining the redshift and CMBR, it also explains gravity."

For the maths.....I think it's a problem of cocktals of consfusions.

That implies problems about our foundamentals.Because the main parameter of these researchs is totally different than a ^pure rational universality.

People even when it's false continues for jobs, I can understand,indeed we all need to eat.But that becomes so ironic, that I am going to begin to analyze in details these stupidities.We can't teach that at universities.It's not possible.Our laws are our laws.

We can't play and laugh with our physicality, objective and realistic.

The pub and the business never must cause problems about our inetrnational language and its series of equations.

I am here to develop my theory,not for being in an ocean of business.

Regards

Steve

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Tissa Perera wrote on Aug. 4, 2010 @ 12:51 GMT
Can a black hole explode?

Is not the singularity within the black hole far less than

Plank length?

/Tissa

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Lawrence B. Crowell replied on Aug. 4, 2010 @ 12:55 GMT
A black hole quantum mechanically radiates in a thermal or blackbody spectra. As it radiates mass away the temperature increases which in turn means it radiates mass-energy out faster. Consequently towards the end ot this process the black hole does violently emit radiation in what might be called an explosion.

Cheers LC

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Steve Dufourny replied on Aug. 4, 2010 @ 16:36 GMT
Hi dear Tessa, Of course never,it's not possible.Because all Spheres(here the BH or the B body if you prefer)have a pure rule of complementarity, theses super mass have a rule, they aren't dedicated to explode,that has no sense.

The equilibrium is logic between mass.They help for the building, all rotates around a center and these spherical BH turn around a center also.....thus why an explosion, we can't confound a star and a BH ...ALL HAS A RULE.

Best Regards

Steve

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Don Limuti (www.zenophysics.com) wrote on Aug. 4, 2010 @ 20:56 GMT
Steve,

I was just quoting John Merryman. He was going back and froth with Lawrence about cosmological inflation. I think John has an interesting model that builds on gravity (it does not explain it) and it helps explain inflation.

The phrase "the vacuum expands and collapses" brought to mind the sheet of rubber that is used to "give a feel" to how general relativity works. The curvature of space-time is represented by the dimples that masses make in the sheet of stretched rubber. The gravity the mass produces is the curvature it causes in the rubber. I think of this rubber universe as being on top of a circular drum.

If the circumference of this drum were to expand stretching all the rubber at once we have something that looks like inflation. The universe is bigger and yet all the masses are in their same relative places on the rubber sheet. A neat visualization of inflation.

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John Merryman replied on Aug. 5, 2010 @ 03:11 GMT
Don,

interesting point about the rubber sheet analogy: Within those gravitational dimples, space is falling inward, but from what? Does the rubber sheet represent flat space? Could it be the sheet is expanding outward between the gravity wells? Such that the two elements balance. This would be far more relativistically coherent. The concept of flat,Euclidian space is that expansion and contraction are balanced. So the "hills" balance out the wells.

My argument is the expansion of space is elemental to space, ie.a form of positive quantum fluctuation. This would explain why it appear, under rigorous scientific examination, to equate with a cosmological constant, not a Big Bang singularity.

This then is only stable up to the level of 3.7k, which explains the smoothness of background radiation,without resorting to Inflation.

It then collapses in causal chain reactions, creating the stringy plasma of interstellar and intergalactic connections, as well as the spatial collapse of gravity.



Not that the pros are buying it,but then epi-cycles lasted for fifteen hundred years, as everyone knew the earth was the center of the universe, just as everyone now knows the only possible explanation for redshift is recessional velocity.

my replies to this discussion will be limited for a week, as I'm writing this on a borrowed iPad,in a hotel room in Lexington Ky., in the bathroom, after everyone else has gone to bed.

Pony Finals and the daughter is the boss at the moment.

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Steve Dufourny replied on Aug. 6, 2010 @ 19:53 GMT
Thank you dear Don for this beautiful explanation.It's interesting this kind of explaination.

Inflation is correlated in my humble opinion to evolution.

I would insist on the spherical system of our Universe.It's logic it's the base of my Theory, an Universal Sphere and its cosmological spheres and its intrinsic quantum spheres......they build these sall spheres....

It is indeed very important, even essential to identify all these spheres and their rotations.The rotation is a proportionality for the mass.

The masses are became more complexs in proportion to their densities and volumes.

Rotations and the inflations are correlated of course.

The universe can't be flat, and therefore it spherize itself, it carries its dynamic into a specific harmonic series.

If this sheet of rubber, with a center spherize, itself is taken in first consideration.It is easy to identify an evolution of rotations and centres.

These spheres undergo specific dynamics and coded, according to an universal oscillation.

At a specific volume and density , this Universal sphere will be towards the perfect equilibrium between mass.

We see our past dear Don we see our past, and we shall see better with these rotating spheres.....the topology is essential for all improvements of our technology.We turn and it's essential.The sphere evolves and complexificates itself.If we don't insert the rotations around a center inside a sphere, never we shall understand where we are .......

Best Regards

Steve

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Don Limuti (www.zenophysics.com) wrote on Aug. 5, 2010 @ 07:52 GMT
John,

I like it! I will get carried away and make a physical model of it.

1. Start with the rubber sheet stretched over the drum.

2. Only this time the drum is full of water and the rubber is floating on the rubber.

3. The circumference of the drum where the rubber attaches can float up and down.

4. When a mass is placed on the rubber sheet it dimples downward and displaces some water.

5. This displaced water pushes the rest of the water in the drum upward. Just like pushing a beach-ball into a bathtub.

6. The average level of the water in the tub stays the same. And the average level of the rubber sheet stays the same.

7. The analogy being that the average curvature of the universe is flat no matter how much or little mass there is in it.

Does that fit with you model?

Good luck with the Pony.

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John Merryman replied on Aug. 5, 2010 @ 12:22 GMT
Don,

Exactly!

I first started to question physics after learning expansion and gravitational contraction are balanced. it seemed for more likely to be a complementary relationship,than the coincidence Big Bang proposes. Modern cosmology really does seem to be a convoluted mess of complex theories, tied together with some rather outrageous fudge factors. It really does seem to be a modern form of epicycles, with some very basic misunderstanding leading to increasingly wild speculations, but those in the field view every Escher Scetch of a mathematical theory as more real than any logical observation. The assumption physics is Counterintuitive has been perverted to mean it is illogical.

Not a big fan of iPad, but it is useful. Thanks for the consideration.....

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T H Ray replied on Aug. 5, 2010 @ 13:09 GMT
"Counterintuitive" means that the logic of naive realism is violated.

Tom

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John Merryman replied on Aug. 6, 2010 @ 00:19 GMT
Tom,

I'm not sure I see your point. There are lots of things which are counterintuitive,but not illogical. The issue of whether the sun moves across the sky, versus the earth rotating would be a significant historical and scientific example. My point is that physics is going to extremes with this.

The idea of block time would be a good example of a mathematical model predicting a fallacy. As a four dimensional geometry can be devised, using the sequence and duration of events as an additional dimension to three coordinates of space, many physicists will argue with all conviction that this dimension of time is physically real and the point of the present is as subjective as any point in space.

Well, the old naive saying that you can't have your cake and eat it too is a more accurate physical description than block time.

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Lawrence B. Crowell wrote on Aug. 6, 2010 @ 17:08 GMT
Tom,

To be fair it might be said that proper time is fundamentally real in relativity. So we might think of the classical mechanical universe as consisting of world lines with their own proper times. Such a world is utterly without any unity, until we include null rays with zero proper time. This provides a way to transform between these various frames with their unique proper times. This is what constructs the “field” called spacetime which permits a transformation between local frames.

Cheers LC

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T H Ray replied on Aug. 6, 2010 @ 17:22 GMT
Of course. It's still a geometric transform, however. That the boundary is zero gives us a fixed point. I can't see at all how this relates to John's rhetoric about "correlation" and "equivalence" between time and distance. The time coordinate is still a simple parameter of reversible trajectory in classical mechanics. Continuous function geometry.

Tom

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Lawrence B. Crowell wrote on Aug. 6, 2010 @ 22:47 GMT
Tom,

Sure, much of what John is referring to is "mysterious." :-) I think John is referring to some popularizations which can end up makiing statements about time eqivalent to space. I think this refers to how the speed of light is a conversion factor between spatial coordinate distance and time.

Cheers LC

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John Merryman replied on Aug. 7, 2010 @ 02:45 GMT
Lawrence,, Tom,

I realize it's geometry, but that makes it a modeling device for defining reality, not a fundamental proerty of it.

Why is it that time is described as one dimension? One dimension of space is a line. Two is area and three is volume. This all seems a rather reductionistic description and modeling is reductionism. it is very useful, but it is also necessary to understand the limits,or it becomes counterproductive, because it distorts further understanding.

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T H Ray replied on Aug. 7, 2010 @ 11:40 GMT
Time _isn't_ "described as one dimension" in general relativity, John. Time is continuous with the geometry of space, as an additional coordinate in a spacetime metric. You cannot seem to grasp that time is an illusion in the classical theory -- that it is a record-keeping device, a way for an observer to correctly determine her position and velocity in spacetime by accounting for the effects of motion relative to other observers.

The proper time limit allows access to boundary conditions that inform us that the universe had a beginning in classical theory. Sure, there may "really" be no such boundary, but that's what quantum gravity is out to explain -- how do nonlocality and uncertainty join with classical mechanics?

It is not contemporary physical theory that limits understanding. One limits one's understanding by starting with false premises.

Tom

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John Merryan replied on Aug. 7, 2010 @ 12:43 GMT
Tom,

The only "fixed point" in time is the present. The projection of past and future are "record keeping devices." Time is not an "illusion." It is an effect of the changing configuration of that which is present. Beginnings and endings are a function of the effect of information of this changing configuration, because the end of one configuration is due to losing it's constituent energy and this energy goes on to other configurations. The process of time goes from past units of configuration to future ones. These units of configuration go from being in the future to being in the past. Beginning and end only apply to the units, not the process. even with Big Bang theory, they now put in the context of multiple universes. So even in this theoretical model, the universe becomes a unit in a larger process.

Looks like I'm stuck here for the entire show, till a week from tomorrow. That means I will always be present, but these days will go from being in the future to eventually being in the past.

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Don Limuti (www.zenophysics.com) wrote on Aug. 9, 2010 @ 22:37 GMT
John,

I continue to like this conversation thanks to you Tom and Lawrence. Let me nit pick the statement: "The only "fixed point" in time is the present". This could mean a lot of things, but I believe that it is intended to convey the thought that at we can have a pure space without time in the present moment. I believe that this is the conviction of many but that it is flawed because space and time in physics always go together. Here is my model:

I have a camera that has a shutter speed duration that is 100 times shorter than any light wavelength that enters the camera. When I take a picture of a garden landscape the image is "black". There is no landscape to see at the present moment and it follows that there is no space at the present monent. In my opinion at the present moment neither space or time exists.

Once we allow reasonable shutter times we start getting reasonable pictures and a world view that has space and time linked. Does the world of physics have reasonable shutter times?

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T H Ray replied on Aug. 9, 2010 @ 22:58 GMT
Don,

We do have " ... pure space without time in the present moment ..." but there's no matter in it. The particles of a quantum non-relativistic universe are entangled to infinity, though.

The reasonable shutter time in physics is called Planck's Constant.

Tom

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Georgina Parry replied on Aug. 9, 2010 @ 23:06 GMT
Don,

is it that it does not exist or only that it can not be observed with a very short shutter time, that does not allow information to be transferred and interpreted? It has to be observed to be experienced, so the experience does not exist, I agree. There is no subjective reality that can be formed from such a short interval.

However there must be a reality that exists that can allow the information to be generated. So that it can be received and interpreted after a longer interval. Can there be unseen reality that is real. Yes. I accept that there is a real rabbit in the magician's hat prior to its extraction. Even if the rabbit climbed in itself and no one say it do so. I accept that the elephant behind the mirror, that no one can see, is still a real material entity. It is not necessary to see it to accept that it is real. Observed reality can not spring fully formed from nothing but time,imo. I do not believe in magic.

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John Merryman replied on Aug. 10, 2010 @ 02:21 GMT
Don,

I agree that a dimensionless point of time would be a complete absence of motion or information, but my arguemnt is that the very concept of time is an effect of motion, much like temperature is an effect of motion. Now if you completely froze motion, like zero shutter speed, nothing would effectively exist. It would be a temperature of absolute zero.

Now ask yourself; How...

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Don Limuti (www.zenophysics.com) wrote on Aug. 10, 2010 @ 23:55 GMT
I appreciate the responses,

Ray, Thanks, of course, the Planck scale! This is what this blog is about. I am suspicious of space without matter and think they rely on each other for existence.

Georgina, Yes, I believe there was a rabbit in the hat before the extraction, but is there a rabbit in the hat right now? I do believe in an "out there in the real world" that consists of space and matter. However I also believe, the matter always brings along a clock.

John, You say time is an effect of motion, I agree with that as far as it goes. But I would go on to say that motion is an integral and continuous part of the world, and therefore we are stuck with time. Of course we can try to hide this nasty thing "time" by limiting our vocabulary to just the terms "distance" and "velocity", kinda like hiding an elephant behind a tree. You go on to say that "every motion is effectively its own clock, so there is no universal flow" This does not make much sense to me. I interpret it as saying something like "If every human carries a clock then time is useless".

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Lawrence B. Crowell replied on Aug. 11, 2010 @ 01:51 GMT
Don,

Even a particle at rest can be thought of as moving at speed c along the direction x_0 = ct. If you observe another particle moving in space with a velocity v there is then a transformation principle --- Lorentz boosts. The result is that time is a local property, or the invariant is proper time, and the proper time for all world lines or geodesics are connected by the symmetries of spacetime.

Cheers LC

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Georgina Parry replied on Aug. 11, 2010 @ 01:59 GMT
Don,

thank you. Re your question, you should ask the rabbit. It knows whether it is in the hat or not. It does not need an outside observer to tell it where it is or when, it just is - really is, somewhere. I don't know if the rabbit has a clock with him though.. I am now picturing the white rabbit from Alice in wonderland!

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John Merryman replied on Aug. 11, 2010 @ 02:43 GMT
Don,

I didn't say time doesn't exist. I'm saying it is an emergent effect of motion, rather than a dimensional basis for it. It is more like temperature, than space. As I see it, the absolute would be the vacuum/space. From its apparent instability arises fluctuation. Time and temperature are effects of this fluctuation. One being the changing configuration and the other being the degree of activity.

It is safe to say that human beings are many orders of emergence beyond that of time and temperature, so if you were to consider them to be illusions based on their being an effect of motion and not the basis for it, what does that make us?

I think that while the rational, linear, left side of the brain is a form of clock, the emotional, non-linear, right side of the brain is a form of thermometer, in that it registers the multitude of energies and influences that we cannot rationally process.

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Don Limuti (www.zenophysics.com) wrote on Aug. 11, 2010 @ 08:07 GMT
Hi all,

Lawrence, I suspect that there is no such thing as a particle at rest. This is a minority position I have taken.

Georgina, My favorite rabbit is Elmer Fudd's nemesis Bugs Bunny. "Where is that pesky rabbit?"

John, I too feel that motion or how particles move is the key to time space and physics. Just because children are an emergent phenomena of their parents I do not call them illusions (at least not all the time).

I just read a most interesting book "Human" by Gazzaniga (left brain/right brain originator) in which the current work of Jeff Hawkin's is outlined. Recommended.

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Lawrence B. Crowell wrote on Aug. 11, 2010 @ 12:58 GMT
Don,

This depends upon what you mean by being at rest. A particle with a significant Compton wavelength λ = ħ/mc (or small mass) interacts with the vacuum so that if one were to perform a sequence of measurements in a Zeno type of process it would be measured to exhibit a Langevin or Brownian type of motion.

Cheers LC

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John Merryman replied on Aug. 12, 2010 @ 21:17 GMT
Don,

That's " waskally wabbit."

It's not simply how they move, but that there is motion to the degree any form of contrast is created, such that one configuration becomes another. Yes, there can be any number of further emergent effects, such as entropy, or even our conscious perception of this process, but change is time.

E. O. Wilson described the insect mind as a thermostat, but it's been shown that ants can count their steps and that's a form of clock/sequence.

Kids start as parents dreams and parents end as kids memories, so maybe we are all illusions.

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Georgina Parry replied on Aug. 12, 2010 @ 22:08 GMT
John,

very poetic- but dreams and memories also require biochemistry. The parent has an ever changing biochemical structure as does the created child. That is the underlying objective material reality separate from experience. There are Continual, ongoing physical /chemical processes (that involve spatial change of position of matter and/or sub atomic particles) whereby all that happens occurs and all that is experienced is generated.

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John Merryman replied on Aug. 13, 2010 @ 02:48 GMT
Georgina,

Trying to peel apart all the levels of emergence is a Sisyphean task, given the degree to which they are bound together. Then again, the desire to take on such tasks is one more layer of the process.

Don't loose sight of the forest for the trees and don't loose sight of the trees for the forest.



If you peel away the poetry, though, the next step is a long way down.

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