Comments on: Shaw Prize for the Accelerating Universe http://blogs.discovermagazine.com/cosmicvariance/2006/06/26/shaw-prize-for-the-accelerating-universe/ Random samplings from a universe of ideas. Mon, 09 Nov 2009 05:18:11 -0600 http://wordpress.org/?v=2.8.4 hourly 1 By: YAPWTMTIOMH http://blogs.discovermagazine.com/cosmicvariance/2006/06/26/shaw-prize-for-the-accelerating-universe/comment-page-1/#comment-18086 YAPWTMTIOMH Wed, 23 Aug 2006 18:34:32 +0000 http://blogs.discovermagazine.com/cosmicvariance/2006/06/26/shaw-prize-for-the-accelerating-universe/#comment-18086 Okay, Yet Another Programmer With Too Much Time on My Hands. Does it not follow that if the farther away an object is, the faster it appears to move...that, as an object gets farther away, it appears to move faster? In effect, there is an apparent accelaration due to distance? Even my limited calculus derives that for an observer on the circumference of a simple circle with an expanding radius. I'm not sure of where the variables fit in such a simple model, for if the expanding radius were "time-like", and the expanding circumference was "space-like" we would have an explanation for the passage of time that we all observe. If the "world line" a particle follows was defined by something equally simple like perhaps a spiral, it would also account for time dliation. Just curious... Okay, Yet Another Programmer With Too Much Time on My Hands.

Does it not follow that if the farther away an object is, the faster it appears to move…that, as an object gets farther away, it appears to move faster?

In effect, there is an apparent accelaration due to distance? Even my limited calculus derives that for an observer on the circumference of a simple circle with an expanding radius. I’m not sure of where the variables fit in such a simple model, for if the expanding radius were “time-like”, and the expanding circumference was “space-like” we would have an explanation for the passage of time that we all observe. If the “world line” a particle follows was defined by something equally simple like perhaps a spiral, it would also account for time dliation.

Just curious…

]]> By: Plato http://blogs.discovermagazine.com/cosmicvariance/2006/06/26/shaw-prize-for-the-accelerating-universe/comment-page-1/#comment-18080 Plato Thu, 29 Jun 2006 14:57:09 +0000 http://blogs.discovermagazine.com/cosmicvariance/2006/06/26/shaw-prize-for-the-accelerating-universe/#comment-18080 Well of all things I came to ressurect, and it had already been done with the point of GRB's. :) More on name. I am rushed this morning so I had to do this quickly. Layman thoughts forming. WMAP distribution? Can it cause some problems in regards to the "information from measure" that are being recieved in regards to how we think of the universe's shape? Well of all things I came to ressurect, and it had already been done with the point of GRB’s. :)

More on name. I am rushed this morning so I had to do this quickly. Layman thoughts forming.

WMAP distribution? Can it cause some problems in regards to the “information from measure” that are being recieved in regards to how we think of the universe’s shape?

]]> By: Sean http://blogs.discovermagazine.com/cosmicvariance/2006/06/26/shaw-prize-for-the-accelerating-universe/comment-page-1/#comment-18079 Sean Thu, 29 Jun 2006 14:46:53 +0000 http://blogs.discovermagazine.com/cosmicvariance/2006/06/26/shaw-prize-for-the-accelerating-universe/#comment-18079 Stephen, yes, we talked about it here: http://blogs.discovermagazine.com/cosmicvariance/2006/01/11/evolving-dark-energy/ GRB's are very bright, but much harder to "standardize" than are Type Ia supernovae. Stephen, yes, we talked about it here:

http://blogs.discovermagazine.com/cosmicvariance/2006/01/11/evolving-dark-energy/

GRB’s are very bright, but much harder to “standardize” than are Type Ia supernovae.

]]> By: Stephen Uitti http://blogs.discovermagazine.com/cosmicvariance/2006/06/26/shaw-prize-for-the-accelerating-universe/comment-page-1/#comment-18078 Stephen Uitti Thu, 29 Jun 2006 14:12:05 +0000 http://blogs.discovermagazine.com/cosmicvariance/2006/06/26/shaw-prize-for-the-accelerating-universe/#comment-18078 Isn't there a paper out using Gamma Ray Bursts (GRBs) instead of SNs to do the same sort of thing? The GRB data is public, even if there aren't alot of them, more data comes in more or less daily. GRBs are more energetic, so if this kind of data can come from them, then a deeper look back into time and space can be achieved. Isn’t there a paper out using Gamma Ray Bursts (GRBs) instead of SNs to do the same sort of thing? The GRB data is public, even if there aren’t alot of them, more data comes in more or less daily. GRBs are more energetic, so if this kind of data can come from them, then a deeper look back into time and space can be achieved.

]]> By: island http://blogs.discovermagazine.com/cosmicvariance/2006/06/26/shaw-prize-for-the-accelerating-universe/comment-page-1/#comment-18062 island Tue, 27 Jun 2006 19:27:22 +0000 http://blogs.discovermagazine.com/cosmicvariance/2006/06/26/shaw-prize-for-the-accelerating-universe/#comment-18062 http://www.lns.cornell.edu/spr/2005-06/msg0069818.html http://www.lns.cornell.edu/spr/2005-06/msg0069818.html

]]> By: Riofrio http://blogs.discovermagazine.com/cosmicvariance/2006/06/26/shaw-prize-for-the-accelerating-universe/comment-page-1/#comment-18085 Riofrio Tue, 27 Jun 2006 15:46:02 +0000 http://blogs.discovermagazine.com/cosmicvariance/2006/06/26/shaw-prize-for-the-accelerating-universe/#comment-18085 Interesting ideas. If c changes but the quantity hc remains constant, then h is increasing and GR-QM are linked. The nice stripes on the graph do seem to rely on many assumptions. If Earth is "defined" as the centre of the Universe, you can always make a choice of reference frames so that this remains so. Just as anyone can observe retrograde motion of planets, the CMB indicates that the Universe expanded faster than the present value of c. One must infer a repulsive inflaton field (Epicycle #1). Supernova and other data indicate that relationship v/c is accelerating, so one must infer another repulsive dark energy (Epicycle #2). We would be fortunate to live in the centre of these forces. Varying c indeed changes observations of galaxies at z=0.5, it affects their luminosity and redshift so that they fit the curve precisely. If a prediction fits the graph of many data points without inferred energies, what does it mean? We would still need corroborating evidence for a "c change." More coming soon. Interesting ideas. If c changes but the quantity hc remains constant, then h is increasing and GR-QM are linked. The nice stripes on the graph do seem to rely on many assumptions.
If Earth is “defined” as the centre of the Universe, you can always make a choice of reference frames so that this remains so.
Just as anyone can observe retrograde motion of planets, the CMB indicates that the Universe expanded faster than the present value of c. One must infer a repulsive inflaton field (Epicycle #1). Supernova and other data indicate that relationship v/c is accelerating, so one must infer another repulsive dark energy (Epicycle #2). We would be fortunate to live in the centre of these forces.
Varying c indeed changes observations of galaxies at z=0.5, it affects their luminosity and redshift so that they fit the curve precisely. If a prediction fits the graph of many data points without inferred energies, what does it mean?
We would still need corroborating evidence for a “c change.” More coming soon.

]]> By: Plato http://blogs.discovermagazine.com/cosmicvariance/2006/06/26/shaw-prize-for-the-accelerating-universe/comment-page-1/#comment-18084 Plato Tue, 27 Jun 2006 14:27:04 +0000 http://blogs.discovermagazine.com/cosmicvariance/2006/06/26/shaw-prize-for-the-accelerating-universe/#comment-18084 It is nice to be able to see how GR works on such a cosmological scale. :) "Energy density" then of course throws in some questions for me, about the dynamical nature of our universe. Are the "quantum perceptions" ready then, to accept the dynamical nature QM and GR in our cosmos as having now shown themself together? It is nice to be able to see how GR works on such a cosmological scale. :)

“Energy density” then of course throws in some questions for me, about the dynamical nature of our universe.

Are the “quantum perceptions” ready then, to accept the dynamical nature QM and GR in our cosmos as having now shown themself together?

]]> By: MindShaper http://blogs.discovermagazine.com/cosmicvariance/2006/06/26/shaw-prize-for-the-accelerating-universe/comment-page-1/#comment-18083 MindShaper Tue, 27 Jun 2006 13:23:19 +0000 http://blogs.discovermagazine.com/cosmicvariance/2006/06/26/shaw-prize-for-the-accelerating-universe/#comment-18083 Rob Knop - <I>Anther way is to just use "rest mass" for mass, and say that the momentum equation is nonlinear (momentum starts to go up faster than the linear relationship once v is an appreciable fraction of c).</I> Thank you. This explanation is clearer (and more complete) than I've read elsewhere, and makes my admittedly amateur understanding of the subject much better. That is, it makes sense. Having worked with radar, laser ring gyros, and instrumentation in aircraft, "nonlinear" is definitely a relationship that I comprehend. Rob Knop -
Anther way is to just use “rest mass” for mass, and say that the momentum equation is nonlinear (momentum starts to go up faster than the linear relationship once v is an appreciable fraction of c).

Thank you. This explanation is clearer (and more complete) than I’ve read elsewhere, and makes my admittedly amateur understanding of the subject much better. That is, it makes sense.
Having worked with radar, laser ring gyros, and instrumentation in aircraft, “nonlinear” is definitely a relationship that I comprehend.

]]> By: Thomas Dent http://blogs.discovermagazine.com/cosmicvariance/2006/06/26/shaw-prize-for-the-accelerating-universe/comment-page-1/#comment-18082 Thomas Dent Tue, 27 Jun 2006 10:46:09 +0000 http://blogs.discovermagazine.com/cosmicvariance/2006/06/26/shaw-prize-for-the-accelerating-universe/#comment-18082 Obligatory addendum: from a particle physicist's viewpoint, the dark energy is very ugly, because it happens on an energy scale which is much, much smaller than all effects that produce vacuum energy in particle physics models that seem to have something to do with reality. Enormous amounts of time and energy have been wasted so far in attempting to put together models which produce anything like the right answer. Also: These nice stripes on the graph rely on a number of assumptions, some of which are currently not well testable - for example the nature of the dark matter that makes up Omega_M, where most standard assumptions do not work very well for small scale structures. Or an assumption that the local Universe is sufficiently homogeneous to extrapolate out to large distances. What if the acceleration is only happening in our cosmic back yard, as it were, due to a local blip in the distribution of matter - in which case it doesn't tell us about the underlying background evolution. The current picture looks self-consistent, but that doesn't mean there are no serious discrepancies left in cosmology. There is a chance that it could be self-consistently wrong, and each of the assumptions has to be further tested. Oh, and 'varying speed of light'? Don't get me started. The speed of light in SI units is *defined* to be a constant number, and you can always make a choice of units so that this remains so. (Relativity looks best in units where c=1.) There is no physical content in 'varying' speed of light, only in dimensionless constants like the fine structure constant. Obligatory addendum: from a particle physicist’s viewpoint, the dark energy is very ugly, because it happens on an energy scale which is much, much smaller than all effects that produce vacuum energy in particle physics models that seem to have something to do with reality. Enormous amounts of time and energy have been wasted so far in attempting to put together models which produce anything like the right answer.

Also: These nice stripes on the graph rely on a number of assumptions, some of which are currently not well testable – for example the nature of the dark matter that makes up Omega_M, where most standard assumptions do not work very well for small scale structures. Or an assumption that the local Universe is sufficiently homogeneous to extrapolate out to large distances. What if the acceleration is only happening in our cosmic back yard, as it were, due to a local blip in the distribution of matter – in which case it doesn’t tell us about the underlying background evolution.

The current picture looks self-consistent, but that doesn’t mean there are no serious discrepancies left in cosmology. There is a chance that it could be self-consistently wrong, and each of the assumptions has to be further tested.

Oh, and ‘varying speed of light’? Don’t get me started. The speed of light in SI units is *defined* to be a constant number, and you can always make a choice of units so that this remains so. (Relativity looks best in units where c=1.) There is no physical content in ‘varying’ speed of light, only in dimensionless constants like the fine structure constant.

]]> By: Jack http://blogs.discovermagazine.com/cosmicvariance/2006/06/26/shaw-prize-for-the-accelerating-universe/comment-page-1/#comment-18081 Jack Tue, 27 Jun 2006 04:05:52 +0000 http://blogs.discovermagazine.com/cosmicvariance/2006/06/26/shaw-prize-for-the-accelerating-universe/#comment-18081 "The one most fundamental thing I've learned from academia is that "anybody not working on what I am working on is wasting their time on an unimportant and uninteresting subject."" The one most fundamental thing *I've* learned is that a great many people have massive inferiority complexes, and that this can express itself in a variety of grotesque ways which have one thing in common: they make the sufferer appear very much stupider than he [probably] really is. See eg Phil Anderson's amazingly dim-witted comments on how cosmology would work if he had been present at the Creation, or R. Laughlin's astounding book, which takes vicarious embarrassment to levels hitherto undreamed-of. “The one most fundamental thing I’ve learned from academia is that “anybody not working on what I am working on is wasting their time on an unimportant and uninteresting subject.”"

The one most fundamental thing *I’ve* learned is that a great many people have massive inferiority complexes, and that this can express itself in a variety of grotesque ways which have one thing in common: they make the sufferer appear very much stupider than he [probably] really is. See eg Phil Anderson’s amazingly dim-witted comments on how cosmology would work if he had been present at the Creation, or R. Laughlin’s astounding book, which takes vicarious embarrassment to levels hitherto undreamed-of.

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