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Author Topic: Is the Universe expanding faster than the speed of light?  (Read 5372 times)

Offline MikeS

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The universe is supposedly expanding and that expansion is increasing to the point where the expansion is faster than the speed of light.  As there are no preferential frames of reference, we must be travelling at the speed of light.

This is obviously wrong, so could it be seen as evidence that the universe is not expanding at that speed and some of the red-shift that is attributed to the Hubble red-shift is actually due to time dilation in the past or time contraction now?
« Last Edit: 24/08/2011 12:29:41 by MikeS »


 

Offline MikeS

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Is the Universe expanding faster than the speed of light?
« Reply #1 on: 24/09/2011 12:16:38 »
From the reference frame of a distant observer, time stands still at both the event horizon of a black hole and an object traveling at the speed of light.
From a distant reference frame, the faster the velocity of an object, the slower the passage of time.

The Universe is supposedly expanding and that expansion is accelerating (possibly at or beyond the speed of light).  This is how it appears to us.  However, from a distant reference frame, the faster the velocity of an object, the slower the passage of time.  If the velocity of the expansion of space is increasing then time is continually dilating in which case the passage of time was faster in the past and is continually slowing (dilating).  This time dilation creates a red-shift that looks identical to the cosmological red-shift.  It looks the same because it is the same.  However, time dilation is not considered when trying to explain the observed cosmological red-shift.

The Universe may well be not expanding anywhere near as fast as we think it is.  In which case we didn't need to invent dark energy.  Why not stick to what we know in preference to inventing things to justify a popular belief?
« Last Edit: 24/09/2011 12:43:48 by MikeS »
 

Offline yamo

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Is the Universe expanding faster than the speed of light?
« Reply #2 on: 24/09/2011 13:39:29 »
The universe is expanding not because the galaxies are moving but because the space between them is increasing...?
 

Offline MikeS

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Is the Universe expanding faster than the speed of light?
« Reply #3 on: 24/09/2011 14:19:42 »
Yes, the mainline view is that galaxies are growing further and further apart because space is being created between them, whatever that means.  I believe that the mainline view that is almost wholly based upon the observed cosmological red-shift being interpreted as being due to the Hubble law is probably wrong.  There are other ways of interpreting the observed cosmological red-shift that don't require the invention of dark energy (to create the expansion) or creation of space to overcome the apparent breaking of the cosmological speed limit (c).
« Last Edit: 24/09/2011 14:33:44 by MikeS »
 

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Offline PhysBang

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Is the Universe expanding faster than the speed of light?
« Reply #4 on: 24/09/2011 14:59:20 »
Shrunk
You have again and again decided to ignore the entire field of cosmology and focus instead on a cartoonish description of cosmological redshift. Why should anyone care at all that you have yet another inane argument about cosmology?

Quote
The universe is supposedly expanding and that expansion is increasing to the point where the expansion is faster than the speed of light.  As there are no preferential frames of reference, we must be travelling at the speed of light.

This is obviously wrong...
You have given us no reason to suppose that it is obviously wrong that we are traveling at the speed of light, none whatsoever.

If you can give us a reason, then please do so.
 

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Offline JP

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Is the Universe expanding faster than the speed of light?
« Reply #5 on: 24/09/2011 21:00:30 »
Shrunk
Speaking as a moderator here:
Physbang, please refrain from using insulting terms such as inane to describe theories.  It falls just short of a personal attack and is definitely not in keeping with site policy to "keep it friendly."
 

Offline MikeS

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Is the Universe expanding faster than the speed of light?
« Reply #6 on: 25/09/2011 08:19:05 »
You have again and again decided to ignore the entire field of cosmology and focus instead on a cartoonish description of cosmological redshift. Why should anyone care at all that you have yet another inane argument about cosmology?

Quote
The universe is supposedly expanding and that expansion is increasing to the point where the expansion is faster than the speed of light.  As there are no preferential frames of reference, we must be travelling at the speed of light.

This is obviously wrong...
You have given us no reason to suppose that it is obviously wrong that we are traveling at the speed of light, none whatsoever.

If you can give us a reason, then please do so.
[/color]

Cosmological red-shift is attributed wholly to the Hubble law.
The Hubble red-shift and type 1a supernova seem to be the only real means of estimating long distance.
Type 1a supernova are a better fit to time contraction in the past than to the Hubble red-shift.
Part of the cosmological red-shift can easily be attributed to time contraction in the past.  This is in full accordance with what we observe.  It does not require anything to be added, no dark energy and no creation of space.


I have given a reason but I will repeat it.  If you believe in Relativity than nothing can exceed the speed of light.  The 'creation of space' is a patch dreamt up to try and cover this glaring problem.

From a distant reference frame, the faster the velocity of an object, the slower the passage of time.
If the velocity of the expansion of space is increasing then time is continually dilating in which case the passage of time was faster in the past and is continually slowing (dilating).  This time dilation creates a red-shift that looks identical to the cosmological red-shift.  This is a prediction of Relativity.


Using the Hubble Law alone as interpretation of the cosmological red-shift must be wrong as the relativistic velocity of the expansion automatically introduces a time dilation factor which should be taken into account.
« Last Edit: 25/09/2011 15:41:13 by MikeS »
 

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Offline MikeS

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Is the Universe expanding faster than the speed of light?
« Reply #7 on: 25/09/2011 08:20:28 »
Shrunk
JP
Thank you.
 

Offline simplified

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Is the Universe expanding faster than the speed of light?
« Reply #8 on: 25/09/2011 16:55:36 »
Would you like to show quantity of redshift of photons from farthest stars please?
 

Offline MikeS

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Is the Universe expanding faster than the speed of light?
« Reply #9 on: 26/09/2011 07:35:00 »
Would you like to show quantity of redshift of photons from farthest stars please?

If you are asking what is the red-shift of the furthest object so far observed then it is about 10.

If you are asking what fraction of the total cosmological red-shift time dilation plays, I have no idea but I believe it to be significant.  Significant enough to ensure the universe is not expanding as fast as the speed of light.
« Last Edit: 26/09/2011 07:45:06 by MikeS »
 

Offline MikeS

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Is the Universe expanding faster than the speed of light?
« Reply #10 on: 26/09/2011 11:27:22 »
If the Universe is expanding at a significant fraction of the speed of light then we are moving at a significant fraction of the speed of light. If so then what we call rest mass is actually relativistic mass and is subject to change depending upon speed?
 

Offline simplified

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Is the Universe expanding faster than the speed of light?
« Reply #11 on: 26/09/2011 15:52:55 »
Would you like to show quantity of redshift of photons from farthest stars please?

If you are asking what is the red-shift of the furthest object so far observed then it is about 10.

If you are asking what fraction of the total cosmological red-shift time dilation plays, I have no idea but I believe it to be significant.  Significant enough to ensure the universe is not expanding as fast as the speed of light.
The photons have lost 9/10 energy :oThen speed of the furthest object=297958848 m/s
 

Offline Phractality

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Is the Universe expanding faster than the speed of light?
« Reply #12 on: 28/09/2011 13:50:54 »
If the Universe is expanding at a significant fraction of the speed of light then we are moving at a significant fraction of the speed of light. If so then what we call rest mass is actually relativistic mass and is subject to change depending upon speed?
Rest mass is the mass of the object in a reference frame which is stationary relative to the object. Comoving coordinates are stationary relative to all objects that are comoving with the origin. So, in comoving coordinates galaxies 10 Gly apart may be stationary relative to each other, even though the distance between them is increasing at a significant fraction of the speed of light. The increasing distance is considered to be an "apparent velocity", and not subject to relativity. So the galaxies are not length contracted or time dilated in each other's comoving coordinates.

You could define a non-comoving coordinate system in which the changeing distance is considered to be a real velocity. In such a coordinate system, each distant galaxy would be length contracted and time dilated in the other's reference frame. The expansion of space would be like a gravity hill, centered on the origin, wherever you chose to place the origin.

Mainstream science uses comoving coordinates almost exclusively when dealing with distances more than a few million light years.
 

Offline yor_on

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Is the Universe expanding faster than the speed of light?
« Reply #13 on: 04/10/2011 18:39:20 »
You know, reading you Phractality I get a feeling that this might be the answer to my question on how to differ between uniform motion and a expansion. But then we come to a dilemma, all as I see it. In relativity there is no 'absolute frame' of reference, same over all the universe. But this description of expansion seems to claim one?

If the difference as seen by a observer in the case of a uniform motion, would present him with relativistic effects by the subjects, but in a expansion (between those objects) instead would be seen (By the far observer) as having no relativistic effects on neither, then we have introduced a 'absolute frame of reference', as it seems to me?

Let's reason around it. In a uniform motion there also has to be relativistic effects. That means that the 'far observer', at rest relative what he observes should find a time dilation and a length contraction for the objects, as well as the objects should see it on the opposite ship. But from a 'black room scenario' inside any of those uniformly moving ships it shouldn't be distinguishable, if I'm thinking right here that means that neither of those ships will be able to differ uniform motion from being 'still'.

If a expansion creates more 'space' then the objects on each side of that 'expansion' should present a 'motion' to each other, relative that constantly growing new 'space' and the distant stars, if I'm thinking right there that is, but still not showing any relativistic effects for our far observer?

The only way that would be possible, to me, seems to be to redefine 'relative uniform motion' into a absolute 'frame of reference', am I right there? That means that all uniform motion must be absolute motion, not relative. Also that you can't freely define one of two objects having a uniform motion as being arbitrarily 'still'.

=
To me it also have to do with the idea of 'energy expended'. In a uniform motion there should be no 'energy expended', but in a acceleration there is always energy expended. Still, as both is expected to give relativistic effects, as I see it, that means that you will have to look outside the 'local reality' at how different 'frames of reference' present themselves to you, relative their 'relative motion' and mass/energy.

But if a expansion doesn't follow those criteria, then I will need to redefine what 'uniform motion' is? As we now introduced something that I can't see how I would be able to differ from 'uniform motion/being still' in a black box scenario? And neither from looking out over the expansion. To define it as there can be no relativistic effects makes it into something else to me.
=

Do we really have proof for no relativistic effects being created by an expansion? alternatively a 'expansion' is poorly defined, and not in line with relativity, again as seen by me.

If all motion is 'absolute' then we should have a universal frame of reference, not a relative, and then there is no way we can define uniform motion as being 'at rest'. Against that are those 'black room scenarios' that clearly state that you can't differ one uniform motion from another, and that all experiments you do inside a uniformly moving ship should turn out the same, no matter your 'speed' relative some other frame of reference.

This one is tricky to me. If I understood you right and 'uniform motion' is differentiable from a expansion, then it seems to me that it also should place the effect at the ships, not in the comparison between 'frames of reference'? To make the last point a little clearer. In relativity the effect of a length contraction, although real for the far observer, will, for the traveler inside that ship, be impossible to measure.

You can see that two ways, either the far observer definition is the true one and the ship has shrunk the traveler inside it included, making it impossible for him to measure it. Or you can see it as I do, as a true statement but from the far observers frame of reference, meaning that the travelers frame of reference will give him a another universe where all distances will be contracted relative him, but also one where his ship never has 'contracted'. So in my world those effects are between frames of reference, and both true. But if we go by the definition of there being two types of 'motion', one represented by a expansion, the other by uniform motion, then it seems I also must stop thinking in frames of reference and relative motion? I need to think about this one, a lot :)
==

The other way would be to define relativistic effects only to accelerations and mass/gravity.
==

There is naturally a third way too, to define all contractions as optical illusions, but that one doesn't play, as far as I can see. Also, what would we then make of a time dilation?
« Last Edit: 04/10/2011 23:36:49 by yor_on »
 

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Is the Universe expanding faster than the speed of light?
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