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Author Topic: Split from Does Dark Energy explain the accelerating expansion of the universe?  (Read 2046 times)

Offline MikeS

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Johann - there are regions of the universe that we can never communicate and can never communicate with us.  Both gravity and light are limited in speed - and thus areas of the universe are cut off from us for ever.  The universe is not gravitationally bound - even the observable universe is not bound and is in fact heading for a cold boring heat death where everything has separated from everything else

That's not necessarily true.  At this present stage of the universe it appears to be expanding fast but there is nothing to say whatever is driving the expansion may not cease and gravity will ultimately stop the expansion and cause the universe to contract.
Nobody knows what is causing the expansion but perhaps it is simply mass being turned into energy (the star burning phase) and energy is causing the expansion (energy expands, the second law of thermodynamics)  This is not a mainstream view.

It could be argued that as gravity has no mass and travels at the speed of light which has been experimentally proven then like a photon it does not experience time (although it carries times arrow) and can therefore from its 'point of view' be everywhere in the universe instantaneously.


 

Offline PhysBang

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That's not just "not a mainstream view", that's a whole pile of wrong.
 

Offline MikeS

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That's not just "not a mainstream view", that's a whole pile of wrong.

It may not be a mainstream view but that in itself does not make it wrong.
The universe may or may not be expanding.  As I understand it there is no definitive evidence that it is.  It's little more than a long established assumption based almost wholly on the red-shift.
See http://www.thenakedscientists.com/forum/index.php?topic=40531.msg364677#msg364677
If you know of other evidence for the expansion of the universe please quote references.

I know you don't agree with the following but what is actually wrong with it?
It could be argued that as gravity has no mass and travels at the speed of light which has been experimentally proven then like a photon it does not experience time (although it carries times arrow) and can therefore from its 'point of view' be everywhere in the universe instantaneously.


 

Offline MikeS

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Dark energy and its many alternatives were dreamt up as a patch to explain problems brought about by the presumed acceleration of the cosmological expansion of space as explained by the interpretation of the Hubble red-shift.

If we were to accept that the observed red-shift is partly due to continued time contraction over most of the life of the universe then the original problem just goes away.  This interpretation does not require anything new.
 

Offline MikeS

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"An object in free-fall is in actuality inertial, but as it approaches the planetary object the time scale stretches at an accelerated rate, giving the appearance that it is accelerating towards the planetary object when, in fact, the falling body really isn't accelerating at all. This is why an accelerometer in free-fall doesn't register any acceleration; there isn't any."
http://en.wikipedia.org/wiki/Equivalence_principle

If we accept the above statement as being true.  We are accepting that acceleration can be an illusion caused by time  not being constant.  That being the case why can we not accept that some of the observed cosmological red-shift and apparent acceleration could be due to a continuous time contraction over most of the life of the universe? 
 

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