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Author
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Topic: Is 'Matter' Contracting As Space Expands?
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Aliet Jacob
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Member # 908
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posted 25. October 2003 08:25
I am investigating the concept of material contraction qua spatial expansion as formulated in the CTMU.
Langan states that he borrowed the idea from Sir Arthur Eddington.
Eddington is said to have remarked playfully that: "if the principle of relativity is to be taken seriously (as it must be) then the theory of the expanding universe might with equal justice be called "the theory of the shrinking atom", insofar as the former merely reflects an anthropocentric view which makes a cosmically-remote process into a variation on a human standard. "
More:
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...an overall-expanding universe in which intervals between galaxies are inflating at an accelerating rate whilst intervals within galaxies remain relatively constant (which is the Hubble picture) is the same as an overall-static universe in which intergalactic intervals are inflating whilst interstellar intervals inside galaxies are contracting at an accelerating rate.
Is this correct?
I am picturing it this way:
Imagine three circles representing the three corners of a triangle.
These circles represent galaxies. Assume that there are observers in those galaxies using 'red-shift machines' (high energy spectrometers).
When the stars in the individual galaxies gravitate towards the center of the galaxies, observers in the other galaxies will observe the other the light from the galaxy to redshift, and infer that the 'other' galaxies are receding and conclude that their 'universe' is expanding.
So, while interstellar distances (seen as galaxies) contract, the intergalactic distances expand.
quote:
But then intervals on the small scale of galaxies are not "actually" contracting, are they? Aren't they? The gravitational distortion of the spacetime metric says that they are, and the sense in which this is relativistically true is exactly reciprocal to the sense in which the expansion of the universe is relativistically true. Just as the galaxies are receding from one another not "through" spacetime but like fixed points on the stretching surface of spacetime, so the individual stars in the "gravitational field" of a galaxy are falling in towards a common centre without moving "through" the space between them.
Thus the expansion is illusory because its cancelled by the contraction and because its not actual in the proper sense.
More:
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The gravitational distortion of the spacetime metric says that the distance between the galaxies is contracting, and the sense in which this is relativistically true is exactly reciprocal to the sense in which the expansion of the universe is relativistically true. Just as the galaxies are receding from one another not "through" spacetime but like fixed points on the stretching surface of spacetime, so the individual stars in the "gravitational field" of a galaxy are falling in towards a common centre without moving "through" the space between them.
Under this argument, the principle of equivalence is applied(by the author) to explain that galaxies do not sprinkle their stars all over space because all those stars accelerate towards the core of the galaxies - wherein lurk massive black holes.
This, I believe would shift the position of dark matter to the cores of galaxies.
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The reason that the stars dont seem not to get to the galactic cores is (in this global view) that gravitational stretching of the curved metric in four dimensions just compensates for the acceleration, cancelling it out over a broad range of stellar velocities to leave a quasi-stable system of stars orbiting in free fall around their common centre of gravitational mass. This cancellation expresses the equivalence of gravitational and inertial mass, according to which a star of small mass "feels a small force" which it resists with a small inertia, whilst a massive star "feels a large force" which it resists with a proportionately large inertia. ...it always works out that, as Galileo showed, any two masses will (all else being equal) move exactly the same in a "gravitational field". It is for this reason that the gloves and screwdrivers released by a butter-fingered astronaut in his orbiting capsule don't have "weight", meaning that they aren't being "pulled" in any direction relative to the local rest frame: The equivalence of gravitational and inertial mass cancels the force (the Ricci curvature).
Source
This of course, means that the universe expands globally and contracts locally (within galaxies).
Aren't Galaxies in an inertial frame of reference?
Doesnt the inflationary universe model assume that they are in a non-inertial frame of reference?
If it does, is that correct? Gravity only exists for us because we are in a non-inertial frame of reference. If we move to an inertial frame, we cease to have weight and cant 'drop' things.
Any ideas?
What is the position majority of scientists take concerning Parcellular mechanics?
[ 25. October 2003, 08:39: Message edited by: Aliet Jacob ]
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gedanken
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posted 26. October 2003 01:06
One aspect worth considering is parsimony. Now chosing a particular scale, as in the units of linear measure, is of course largely unconstrained and human defined.
The problem comes in that the choice, once made, needs to be anchored in some reference. The best reference is one based in parsimony, in which the largest number of other useful or important aspects stay constant. For example we have correspondence principles that under many conditions classical mechanics should provide very accurate results. Any change of reference or basis that in essence varies the relationships of classical mechanics as the universe expands seems to be less useful than a reference in which those relationships stay constantly described with constant numerical factors.
So I would try to figure out if such variation of multiple factors or relationships is inherent in the particular view (actually modification of view in a different meaning of 'view') being proposed. This is much like questions of which reference frame to use. The "mach number" is simply a scale reference change, for example, very useful for calculation and scaling of air flow issues such as airplane design and modeling. But a variable reference with regard to classical mechanics would make mathematical calculations very difficult--thus not parsimonious choice.
Another useful way to look at this is to recognize that "relativity" is misnamed. It should have been called the theory of invariants, flipping the notion on its head. Because the very concept of relativity is that each viewer can calculate what the other viewer would see of the same situation. No particular view is more "right" than any other, but one can be transformed into the other by simple mathematical equation. It is not an anthropomorphic error of some sort to choose a particular viewpoint as the reference of choice, even if that choice happens to be a reference frame in which you yourself are at rest. Rather the choice is simply which makes the calculations easy. You can translate it in the end to any other reference frame, as others request for example, without "viewpoint discrimination" of any sort.
(Of course this is all based on a model of the real world in which all viewers would be able to come to exact mathematical agreement on "events" with such translations between them as the only difference in viewpoint, as to the real world thus being otherwise "invariant".)
You actually use the relativity concept in part of the statement.
[Edited to remove reference to distribution of dark matter. That point did not make sense, or was not relevant to the original.]
quote:
Aren't Galaxies in an inertial frame of reference?
Calculations are based on a reference frame. Parsimonious calculation often demands use of an intertial frame of reference. But no one or object (even galaxy) is "in" some particular reference frame on its own, that is a viewer's descretion issue. The object is always simultaneously in all reference frames of relevance, and it is simply a matter of translating from one reference frame to another when desiring a different view.
[Edit ...]
I think that an "inertial" frame of reference only makes sense when constrained to a region in which Euclidean assumptions can be valid, such as a sufficiently small region.
If there are black holes contained within, that seems difficult to make as a sensable statement.
And of course one could define (in the classical manner) an interial reference frame with "gravity" declared as a force. I don't think that is the type of frame that you were talking about, so the alternative is correctly described in which gravity is equated to an accelerating (and thus non-inertial) reference frame. Except for the "black hole" issue, curvature may be sufficiently small that a center of mass based "iniertial" frame makes sense for galaxy. In that sense, "in" an inertial frame could be taken as meaning that an inertial frame exists with CM of the galaxy at (0,0,0) (or some linearly translated equivalent). But as such, the self attraction must be considered as a 'force', as opposed to considering gravity of the star's interaction as curved space, would it not?
This link tends to support this.
[ 27. October 2003, 01:29: Message edited by: gedanken ]
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Aliet Jacob
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posted 27. October 2003 05:07
There are 4 (or 5 - I have forgotten the last one) ideas which would need to be addressed before we get down to the issue (at least for my benefit):
1. The expansion of the universe is caused by residual energy left over from the big bang - per CMBR.
2. The (accelerating) expansion of the universe is caused by vaccum energy released as space expands (this is the one whose investigations gave a null result?)
3. The expansion of the universe is caused by the repulsive force (Einsteins [non-zero] Cosmological constant) exceeding gravitational attraction.
4. The expansion of the universe is caused by dark matter
5. ?
We must bear in mind the difference between the doppler redshift and the gravitational redshift. Gravitational redshift is what stretches light wavelengths when its at a point where gravitational force is strong and thus slows down time as per the twin paradox.
Gravitational redshift, is the result of expanding space between galaxies as per ERSU (Extended Rubber Sheet Universe). According to GR, the expansion of the universe does not consist of objects actually moving away from each other - rather, the space between these objects stretches. Any light moving through that space will also be stretched, and its wavelength will increase - i.e. be redshifted.
Is it correct, based on the above, to note that stretching space slows down the speed of light? (and therefore make the argument YECers make that the speed of light is slowing down?)
Dirac proposed that fundamental constants of physics will change over time (were his ideas debunked?)
Can the cosmological constant remain constant in the face of accelerating expansion?
What is the position of scientists regarding Weinberg's anthropic principle which offers to explain the cosmic constants relative to 'conflicting'/puzzling observations? (this I read in Wikipedia)
Note that its different from the 'fine tuning' anthropic principle propounded by Tipler and Barrow WAP and SAP, which are teleological.
(Moving to the domain of GUTs...)
I have looked partly at the work of Richard Quist (and it seems to be quite different from Arthur Eddington's).
This is his argument:
A. Instead of assuming the universe started from the big bang, assume it existed but was in a condition of unity (as before the big bang).
B. From that point, the velocity of light began to contract relative to the itself and relative to the size of the universe. This is consistent with an expanding universe (as explained above - highlighted)
C. "With this view there would still be an initial actual expansion of the overall size of the Universe accompanying the initial contraction of the size of space within the Universe, but this would eventually cease and the apparent expansion of the Universe that we observe today would be fully the result of a contraction in the size of space within the Universe. This point of view means that time and space within the Universe began as the result of a big shrink."
D. This 'shrinking concept is supported by John Moffat et al's proposal (debunked yet?) that that the speed of light was much faster at the beginning of the Universe.
But I think the main idea rests in B and C above. Anyone able to address them? I got lost at C.
Consequences of this contraction include an alternative explanation of the big bang:
quote:
the contraction of the size of space relative to itself and relative to the overall size of the Universe can be considered to have begun simultaneously with the initial expansion of the Universe at the beginning of time within the Universe. That there is an expansion of the Universe accompanying this contraction at the beginning means that the Universe as we know it can still be considered to have sprung from an initial singularity. There is also another possible characteristic for this initial expansion and contraction. The initial singularity could have begun to expand to a small degree over an extremely short period of time, say on the order of Planck's time, approx. 2(10exp.-43) seconds, and then, the size of space and energy within the singularity, which had expanded with the singularity, would have contracted back to less than it's original size, creating space and less density within the original structure. This process of expansion and contraction would continue, eventually producing the Universe we see now. Of course, it is also possible that the singularity expands to a greater extent before contraction occurs. The exact nature of the expansion will be addressed later. The essential difference with this expansion-contraction approach to describing physical phenomena as compared to the conventional approach is that the fundamental action in reality is an expansion and contraction of space, energy, and matter, with the net result being that matter, energy, and space become contracted relative to both their own past and the overall size of the Universe.
It also explains time acceleration and gravity.
The whole argument is in the link below.
http://www.geocities.com/richardwquist/intro82503.html
STEVEN CARLIP AND SACHINDEO VAIDYA in the Nature Article Cosmology (communication arising): Do black holes constrain varying constants? state that: "Tentative observations of shifted spectral lines in distant quasars have rekindled interest in Dirac's old idea that the fundamental 'constants' of physics may vary over time. Davies et al. have argued that black-hole thermodynamics favours theories in which the speed of light, c, decreases, and does not favour those in which the fundamental electronic charge, e, increases. Here we show, however, that when the entire thermal environment of a black hole is considered, no such conclusion can be drawn. Although black-hole features such as mass quantization may still constrain models with varying 'constants', thermodynamics probably cannot."
Back to Arthur Eddington's 'shrinking atom'.
Ged states that relativity is misnamed and should actually be called the law of invariants "Because the very concept of relativity is that each viewer can calculate what the other viewer would see of the same situation. No particular view is more 'right' than any other, but one can be transformed into the other by simple mathematical equation"
What would be the place of CPT invariants under such circumstances?
About parsimony, I dont see how an inflationary universe in any more parsimonius than a conspansive universe.
Ged states 'A distributed object must be described in terms of its distribution.' I believe this is putting the cart before the horse because that is exactly what we are trying to explain. I see no instance of 'choosing' a viewpoint that I have comitted, so I am unable to answer ged's question 'What is the basis of choosing?'. The redshifting is supposed to be global - ie in all viewpoints.
In response to my question concerning galaxies being in an inertial frame, ged states: "Calculations are based on a reference frame. Parsimonious calculation often demands use of an intertial frame of reference. But no one or object (even galaxy) is "in" some particular reference frame on its own, that is a viewer's descretion issue."
Ged, do I take this to mean you disagree with the idea that there are inertial and non-inertial frames of reference?
Newton's second law states that an object in an inertial frame of reference must not be accelerated. Are you stating that galaxies are in a non-inertial frame of reference - except for convenience in calculations?
We only account for gravity of objects on earth because we are in a non-inertial frame of reference.
Lpetrich asks: "The problem with this expanding/contracting is expansion/contraction relative to what? To their previous states?"
Yes. The fundamental constants will vary relative to their previous values. It has been argued that lightspeed is dimentionful constant and therefore doesnt change.
There is the argument that: "Now suppose that the speed of light is changing. It can be meaningful only if it can be detected by measurements. To perform measurements we need units. Units do not exist in nature and are invented by people to express quantitative relations in nature which exist. Units to measure length, time, speed, etc. are always expressed in terms of some combination of fundamental constants. Performing measurements means comparing the measured value to a particular combination of fundamental constants. Measuring a fundamental constant means comparing fundamental constants between themselves. Physical laws must not depend on the particular choice of units. Below we illustrate that whatever units are used to measure the speed of light, the claim that the speed of light is changing leads to nonsense."
By V.A. Dzuba http://www.phys.unsw.edu.au/~dzuba/varyc.html
Lpetrich states: 'Also, in Langan's scenario, more than atoms have to shrink. Distances between between objects in orbits maintained by gravity also have to shrink. This can happen as a result of changing the gravitational constant, but this change has to be significantly slower than the rate of orbiting to avoid disrupting the orbit dynamics. Cosmological times are about 10 billion years, and orbit times in clusters of galaxies approach that value.'
I agree. I would rather we focus on Eddington's ideas. Eddington was not serious about 'shrinking atom'. He used it more as a metaphor (Langan does state that Eddington made the comments facetiously) and Langan takes and 'retools' it.
I am more keen on the ideas of galaxies contracting and how we would interpret the redshift. I believe galaxies represent matter and inter-galactic intervals represent space so "material contraction qua spatial contraction" can be examined in that 'sober' light. Langan states that Eddington "was skirting the edges of an important duality principle."
Important:
Langan states that cosmic expansion is inconsistent with the reality concept with states that reality is analytically self-contained. So the expansion (an ectomorphism) raises the question: "Where is it expanding (in) to?"
So there is a paradox because ectomorphism is inconsistent with self-containment (I know I sound like Chaitin ![[Smile]](smile.gif) )
He resolves the paradox by positing endomorphism "whereby things are mapped, generated or replicated within themselves. Through conspansive endomorphism, syntactic objects are injectively mapped into their own hological interiors from their own syntactic boundaries."
He adds: "As a result, new states are formed within the images of previous states. Nothing moves or expands “through” space; space is state, and each relocation of an object is just a move from one level of perfect stasis to another. This ties conventional motion, in which worldlines are constructively created by additions of state in Minkowski diagrams, to differential endomorphism, in which the internal descriptive potentials of attributes are cumulatively restricted."
If you agree with the idea that reality is self-contained, you will need to explain where the universe is expanding to. Thats the basis of his argument.
There are other arguments about requantization and the extended superposition principle etc
Another important argument
"Conspansive duality, the role of which in the CTMU is somewhat analogous to that of the Principle of Equivalence in General Relativity, is the only escape from an infinite ectomorphic “tower of turtles”. Were the perceptual geometry of reality to lack a conspansive dual representation, motion of any kind would require a fixed spatial array or ectomorphic “background space” requiring an explanation of its own, and so on down the tower. Conspansion permits the universe to self-configure through temporal feedback."
He makes good arguments: (1) If you agree that there is an infinite ectomorphic tower of turtles that poses a paradox relative to our definitions of reality and 'universe' (2) If you agree with how he resolves the paradox.
Ideas please.
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Aliet Jacob
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posted 27. October 2003 05:20
Ged, from your link, I find the above statement:
"An extragalactic reference frame is assumed to approximate an inertial reference frame through Mach's Principle, and through the distance to the galaxies and quasars, making their transverse motions insensible to proper motion measurement."
I believe interplanetary reference frames are inertial to a large degree. Intergalactic would be even more inertial no?
Ged states: "And of course one could define (in the classical manner) an interial reference frame with "gravity" declared as a force. I don't think that is the type of frame that you were talking about, so the alternative is correctly described in which gravity is equated to an accelerating (and thus non-inertial) reference frame."
I wasnt talking about gravity as the curvature in space-time. I believe when we are talking about reference frames, we are discussing SR principles.
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The Pixie
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posted 27. October 2003 07:30
A couple of points about conspansion that I cannot understand:
My understanding is that at the big bang the universe had zero (internal) size. Would that not cause a problem if it has to be stretched into a volume of finite size?
Why is it that interstellar and interatomic distances are shrinking, but intergalactic distances are not? I believe that the accelerating expansion of the universe is a prediction that CTMU and is a consequence of conspansion, but I have never heard of a satisfactory explanation of how it works.
The Pixie
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gedanken
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posted 27. October 2003 09:48
quote:
Ged states 'A distributed object must be described in terms of its distribution.'
Yes, I went back and deleted this earlier, but you must have already been composing your reply. It was not a coherent thought, as I had misunderstood the original point.
quote:
I wasnt talking about gravity as the curvature in space-time. I believe when we are talking about reference frames, we are discussing SR principles.
Yes, I agree. But to be "Special Relativity" relevant, we must take a sufficiently small region of space that Euclidean approximation is reasonably accurate for geometry. If so, then it is meaningful. But I do not know the degree of error that can be tolerated with respect to a given question, but I suspect it may be sufficient for reasonable approximation.
If so, then we get back to the reference frame questions, and I am fairly comfortable with my SR knowledge. So let me go back to figure out the original question (I may edit more).
But I would be careful on jumping from interplanetary to intergalactic levels, as the jump in size introduces greater curvature away from Euclidean approximations being valid for questions. I cannot answer the question at the level of how much curvature is acceptable.
But one must also be careful in what one means when one says an object is "in" an inertial frame. Once again, the center of mass, considered (0,0,0) of a particular frame, and also choosing that frame appropriate with regard to rotation, then such a frame would be reasonably described as "inertial". But the galaxy is generally (slowly) rotating about its CM, so one must find a non-rotating ref frame of relvance. I don't know if this affects your point, however, just minor details.
From OP:
quote:
Thus the expansion is illusory because its cancelled by the contraction and because its not actual in the proper sense.
This is at least where one must be careful with regard to distance measure per se. I would say that distance measure must first be given a reference by correspondence principle to classical mechanics in our space, such as conditions show it to apply. The local galaxy's expansion/contraciton is measured relative to that measurement system. It does not provide a new reference system scale parsimoniously with all the other observations (such as classical mechanics in our local world). So one does not (even in SR) get to change scale using the (presumed) galaxy contraction as a scale factor--thus I am questioning the longer argument of the OP.
[ 27. October 2003, 10:27: Message edited by: gedanken ]
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chimp
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posted 27. October 2003 13:49
quote:
Pixie:
A couple of points about conspansion that I cannot understand:
My understanding is that at the big bang the universe had zero (internal) size. Would that not cause a problem if it has to be stretched into a volume of finite size?
Why is it that interstellar and interatomic distances are shrinking, but intergalactic distances are not? I believe that the accelerating expansion of the universe is a prediction that CTMU and is a consequence of conspansion, but I have never heard of a satisfactory explanation of how it works.
The Pixie
The conventional model of an expanding spacetime is sometimes depicted by an inflating balloon, where galxies[matter] and forces are represented as constants and spacetime expands with radius R. If my interpretation is correct, the inverse of the expansion of spacetime is a relative perspective effect, such, that a shrinking object gives the illusion of receding motion. Distance and time scales shrink in such a way as to give distance/time = c , for a photon of light.
I found this interesting conspansion article while doing a web search:
http://www.iomas.com/gina/ultrahiq/Mega-Society/NoesisMay/SupernovaCL.asp
quote:
The idea behind the CTMU is to use advanced logic, algebra and computation theory to give spacetime a stratified computational or cognitive structure that lets ERSU be “inverted” and ERSU paradoxes resolved. To glimpse how this is done, just look at the ERSU balloon from the inside instead of the outside. Now imagine that its size remains constant as thin, transparent layers of parallel distributed computation grow inward, and that as objects are carried towards the center by each newly-created layer, they are proportionately resized. Instead of the universe expanding relative to objects whose sizes remain constant, the size of the universe remains constant and objects do the shrinking…along with any time scale expressed in terms of basic physical processes defined on those objects. Now imagine that as objects and time scales remain in their shrunken state, layers become infinitesimally thin and recede outward, with newer levels of space becoming “denser” relative to older ones and older levels becoming “stretched” relative to newer ones. In the older layers, light – which propagates in the form of a distributed parallel computation – “retroactively” slows down as it is forced to travel through more densely-quantized overlying layers.
To let ourselves keep easy track of the distinction, we will give the ERSU and inverted-ERSU models opposite spellings. I.e., inverted-ERSU will become USRE. This turns out to be meaningful as well as convenient, for there happens to be an apt descriptive phrase for which USRE is acronymic: the Universe as a Self-Representational Entity. This phrase is consistent with the idea that the universe is a self-creative, internally-iterated computational endomorphism.
[...]
E.g., if at any point it takes n time units for light to cross the diameter of a proton, it must take the same number of units at any later juncture. If the proton contracts in the interval, the time scale must contract accordingly, and the speed and wavelength of newly-emitted light must diminish relative to former values to maintain the proper distribution of frequencies. But meanwhile, light already in transit slows down due to the distributed “stretching” of its deeper layer of space, i.e., the superimposition of more densely-quantized layers. Since its wavelength is fixed with respect to its own comoving scale (and that of the universe as a whole), wavelength rises and frequency falls relative to newer, denser scales.
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Aliet Jacob
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posted 28. October 2003 02:06
The Pixie,
quote:
Why is it that interstellar and interatomic distances are shrinking, but intergalactic distances are not? I believe that the accelerating expansion of the universe is a prediction that CTMU and is a consequence of conspansion, but I have never heard of a satisfactory explanation of how it works.
Interstellar distances would be shrinking because gravitational attraction pulls the stars towards each other - which ultimately lead to black holes.
"Interatomic" is not part of the argument - except perhaps as a metaphor.
The accelerating universe is not a CTMU prediction. Indeed, CTMU argues for a relatively 'static' universe because every apparent 'expansion' is cancelled by a corresponding contraction.
I think the explanation, per Sir. Arthur Eddington is logical.
The only questions that remain are:
1. Why is space stretching? (this will influence below) is it because of:
(a) Anti-gravity
(b) Residual heat from the big bang per CMBR
(c) Repulsive cosmological constant
(d) Dark matter 'stretching' it
(e) Is our 'universe stable' because of where we occupy (anthropic principle) hence influencing what we observe - constant speed of light?
(f) Galaxies are contracting hence increasing intergalactic space
(g) Other
2. Why can't we say that the stretching of space as caused by the movement of stars in other galaxies towards the center of those galaxies, expecially considering that galaxies are in an inertial frame of reference? I use 'inertial frame of reference' to mean that galaxies are not in (surrounded by) a gravitational field.
Responses to these questions will dictate whether we need spend any more time on conspansion.
[ 28. October 2003, 02:14: Message edited by: Aliet Jacob ]
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The Pixie
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posted 28. October 2003 04:25
Aliet
I have just reread your OP and I realise we have very different understandings of "conspansion". It is my understanding that everything in reality is shrinking, but that, as reality maintains the same (extrinsic) size, to the internal oberser reality is expanding. Fom the web site Russell linked to:
quote:
Accordingly, the universe as a whole must be treated as a static domain whose self and contents cannot “expand”, but only seem to expand because they are undergoing internal rescaling as a function of SCSPL grammar. The universe is not actually expanding in any absolute, externally-measurable sense; rather, its contents are shrinking relative to it, and to maintain local geometric and dynamical consistency, it appears to expand relative to them.
The idea is that if reality was to be rescaled so that it, and everything in it, was half the size, no one would notice. That would involve making interatomic distances half the size, interstellar distances half the size and (one would imagine) intergalactic distances half the size. Eddington's idea is not a metaphor, it is what the CTMU claims is actually happening. And really this is just a point of view change, so I would not argue it was wrong as such.
Except for some reason it is not happening for intergalactic distances. The web page is specifically about how conventional theories are unable to account for the accelerated expansion of the universe, but that CTMU predicts exactly that. I presume this is because intergalactic distances maintain the extrinsic metric, rather than conspanding. I was unable to find anything on that web page that actually went through the logic of why this should be so, despite this being the specific claim on the page (but maybe I just missed it).
Russell
quote:
The conventional model of an expanding spacetime is sometimes depicted by an inflating balloon, where galxies[matter] and forces are represented as constants and spacetime expands with radius R.
This model makes sense at t=0, when R=0. How does the CTMU cope at t=0 with R(obs) = 0. If reality has a constant, non-zero size then we have an infinite scaling factor, or does CTMU not have R(obs) = 0 at t=0?
Pixie
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chimp
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posted 28. October 2003 06:10
quote:
This model makes sense at t=0, when R=0. How does the CTMU cope at t=0 with R(obs) = 0. If reality has a constant, non-zero size then we have an infinite scaling factor, or does CTMU not have R(obs) = 0 at t=0?
Pixie
The universe is externally undefined with respect to size and duration.
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Aliet Jacob
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posted 28. October 2003 08:30
quote:
It is my understanding that everything in reality is shrinking, but that, as reality maintains the same (extrinsic) size, to the internal oberser reality is expanding.
Thats fine so long as you can provide supporting evidence. I too can claim that everything in reality is turning to liquid.
Whats important is the evidence.
quote:
The idea is that if reality was to be rescaled so that it, and everything in it, was half the size, no one would notice.
I do not agree.
The speed of light has not changed. If things shrink, our brains would have to be smaller, we would notice the days are shorter, our circuits would overheat, the density of things will increase...
Where would the energy/force required to effect this contraction come from? And how exactly will it be made to cause the shrinking?
quote:
Eddington's idea is not a metaphor
Eddington was joking and Langan states as much.
This is both on the web and in the CTMU paper. Feel free to disprove this.
Eddington does not argue that reality has been (uniformly) scaled. Those would be Langan's ideas.
quote:
The web page is specifically about how conventional theories are unable to account for the accelerated expansion of the universe, but that CTMU predicts exactly that
CTMU does no such thing.
Please provide some evidence that CTMU does predict accelerated expansion.
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chimp
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posted 29. October 2003 01:29
quote:
CTMU does no such thing.
Please provide some evidence that CTMU does predict accelerated expansion.
Incorrect Aliet Jacob.
If distance and time scales are uniformly shrinking, such, that local Lorentz invariance is preserved, then the process is accelerated, which would appear to be an accelerated cosmic expansion to local observers.
http://www.iomas.com/gina/ultrahiq/Mega-Society/NoesisMay/SupernovaCL.asp
quote:
Because self-configurative spacetime grammar is conspansive by necessity, the universe is necessarily subject to a requantizative “accelerative force” that causes its apparent expansion. The force in question, which Einstein symbolized by the cosmological constant lambda, is all but inexplicable in any nonconspansive model; that no such model can cogently explain it is why he later relented and described lambda as “the greatest blunder of his career”. By contrast, the CTMU requires it as a necessary mechanism of SCSPL grammar. Thus, recent experimental evidence – in particular, recently-acquired data on high-redshift Type Ia supernovae that seem to imply the existence of such a force – may be regarded as powerful (if still tentative) empirical confirmation of the CTMU.
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The Pixie
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posted 29. October 2003 03:51
Aleit
Before proceeding, I better point out that I do not believe in conspansion or the CTMU, and many of the difficulties you point out are, as far as I am concerned, perfectly valid. For example,I asked on a CTMU forum about what happens to force and energy as the universe shrinks (without getting any reply). I think the theory goes that time also conspands, so while the speed of light is constant so is the observed time it takes to travel between two conspanding points. Thus there is no apparent change to us.
Eddington's idea was offered as a joke originally, I think everyone agrees with that, but CTMU extends the joke to reality, not to a metaphor.
The web page Russell linked to is specifically about the problem modern physics faces with the accelerated expansion of the universe. And it further claims that the CTMU explains exactly why this is so. Now, I do agree that the web page does not in any way justify that claim, but the claim is definitely made.
Perhaps Russell could comment on whether conspansion is a uniform shrinking of all distances across reality or whether it is a non-uniform gravity-induced contraction.
The Pixie
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Aliet Jacob
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posted 29. October 2003 04:01
This belongs here:
Just to conclude on conspansion:
There is no paradox to be resolved:
Langan's question concerning ectomorphism "Where is the universe expanding into if the universe is the power set of space and time?" is a wrong question.
quote:
This question is based on the ever popular misconception that the Universe is some curved object embedded in a higher dimensional space, and that the Universe is expanding into this space. This misconception is probably fostered by the balloon analogy which shows a 2-D spherical model of the Universe expanding in a 3-D space. While it is possible to think of the Universe this way, it is not necessary, and there is nothing whatsoever that we have measured or can measure that will show us anything about the larger space. Everything that we measure is within the Universe, and we see no edge or boundary or center of expansion. Thus the Universe is not expanding into anything that we can see, and this is not a profitable thing to think about. Just as Dali's Corpus Hypercubicus is just a 2-D picture of a 3-D object that represents the surface of a 4-D cube, remember that the balloon analogy is just a 2-D picture of a 3-D situation that is supposed to help you think about a curved 3-D space, but it does not mean that there is really a 4-D space that the Universe is expanding into.
QED.
A metal bar that expands and contracts does not earn the expression "self-inclusive" by that virtue alone. Like I said, understand the difference between hology, conspansion, closure, endomorphism, homogenity and holography (Pribrams) and all will be clear.
I respect the fact that Langan is guessing. As Dembski says, Science starts with conjectures which are taken through trial and error.
If galaxies were contracting at the hubble constant Ho = v/d, (where v is the galaxy's radial outward velocity in other words, motion along our line-of-sight, d is the galaxy's distance from earth, and Ho is the current value of the Hubble Constant) things wouldnt be the same.
Unless he wants to appeal to the cosmological anthropic principle (which he would again 'retool' in an ad-hoc manner and extend arbitrarily [to get the Telic Principle] the way he 'extends' the superposition principle, the equivalence principle and the copernican principle)
Langan has to account for the observation that Galaxies that are further away seem to be moving much faster than those that are close.
He has to provide the causal mechanism for this contraction and expansion, where the energy to effect it comes from, what happens to the energy netween the expansion and expansion etc.
Russel, Langan's speculations do not amount to any evidence of CTMU making predictions.
In fact, Langan has admitted that TOEs, by definition, do not make any immediate predictions.
If CTMU made predictions and was falsifiable, it would be a scientific theory!
That would be in conflict with the idea that its supertautological, metamathematical, metascientific and metalogical.
Your eisegesis of the CTMU is going overboard.
Pixie asks good questions. Your response to them and mine might lend a lot of credibility to this invisible contraction you speak of.
[ 29. October 2003, 04:53: Message edited by: Aliet Jacob ]
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Aliet Jacob
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posted 29. October 2003 04:38
Langan's formulation of the MAP reveals the fact that he pictures the universe as a(n expanding) baloon: ie, when he writes "closed", he means "sealed".
Which is incorrect.
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