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Author Topic: Is this the cause of cosmological expansion?  (Read 4604 times)

Offline MikeS

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Is this the cause of cosmological expansion?
« on: 08/08/2011 09:49:40 »
We believe the universe to be expanding because of the red shift of distant objects and we believe that expansion to be accelerating.

We do not know what is causing this accelerating expansion.

What if it is something as simple as radiation pressure from photons that is the cause of the universe expanding?  The energy imparted by individual photons is minute but there are an awful lot of them. We know that photons can impart their energy as in a solar sail.
http://en.wikipedia.org/wiki/Solar_sail
Energy is subject to entropy and expansion is a way of accomplishing this.  All stars, past and present are adding to this radiation pressure.  As stars are spread throughout the universe, so the pressure is evenly distributed.  It has no centre from which to expand.
http://en.wikipedia.org/wiki/Radiation_pressure

The universe is in the star burning phase, nuclear fuel is being burnt and energy produced (mass is being converted into energy).  Eventually all of the fuel will be consumed at which point gravity will be free to stop the expansion and cause the universe to contract.

The mass/energy ratio must be slowly changing in this phase of the universe in favor of energy.  To keep the speed of light constant time will be contracting.



 

Offline PhysBang

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Is this the cause of cosmological expansion?
« Reply #1 on: 08/08/2011 19:15:35 »
Well, if we believe in the General Theory of Relativity, we know exactly what is causing the expansion: we live in a universe with a certain sort of geometry.
 

Offline MikeS

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Is this the cause of cosmological expansion?
« Reply #2 on: 09/08/2011 08:19:43 »
Well, if we believe in the General Theory of Relativity, we know exactly what is causing the expansion: we live in a universe with a certain sort of geometry.

But we don't know what that geometry is.  We don't know whether the Universe is finite or infinite.

The universe appears to be expanding because of the Hubble red-shift but we do not know how significant that is. 


The mass/energy ratio must be slowly changing in this phase of the universe in favor of energy.  To keep the speed of light constant time will be contracting.



If time is contracted now, in comparison to the distant past then light from the distant past will be red-shifted relative to us now.

Time contraction could be more significant than the Hubble red-shift.
For example.  If time contracted sufficiently in comparison to the distant past, the universe 'could' be contracting  but the Hubble red-shift would falsely indicate the exact opposite.

If time is still contracting then this would falsely 'appear' from the perspective of Hubble's Law to equate to an acceleration of the expansion.

Relying on Hubble's Law is like putting all of your eggs in one basket.  Time contraction is an alternative solution to explain red-shift but it gives totally different results.
« Last Edit: 09/08/2011 12:38:39 by MikeS »
 

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Offline PhysBang

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Is this the cause of cosmological expansion?
« Reply #3 on: 09/08/2011 16:03:48 »
Shrunk
Relying on Hubble's Law is like putting all of your eggs in one basket.  Time contraction is an alternative solution to explain red-shift but it gives totally different results.
Why is it that the horribly ignorant must assume that all scientists are as ignorant as they are?

Contemporary cosmology does not simply rely on Hubble's Law alone.

MikeS, if you have a theory of some kind of "time contraction", then let's see you compare your theory to some actual results.
 

Offline MikeS

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Is this the cause of cosmological expansion?
« Reply #4 on: 09/08/2011 16:38:30 »
Here is a result:-
"Once upon a time, time was different. Supernova explosions in the early universe appear to age more slowly than today's supernovae, as if time itself was running slower back then, according to a recent series of astronomical observations.""In the new research, an international team of astronomers have gone much further by monitoring 13 supernovae at a range of redshifts, and therefore a range of distances. The earliest and most distant of these slow-mo explosions appeared to age at only about 60% of the normal rate seen in supernovae today."
http://www.newscientist.com/article/dn13792-cosmic-time-warp-revealed-in-slowmotion-supernovae.html

The mainstream explanation of course is expansion of the universe but it could just as easily be that time actually was dilated back then.

Most(All?) of the evidence to support the cosmological red-shift works just as well for time dilation/contraction.

We know that clocks run at different rates depending upon local gravity why does it cause you to become so rude when I suggest that clocks may have run slower in the past.  Apparently I mistakenly mistook this for a new theories forum.

« Last Edit: 11/08/2011 14:41:46 by MikeS »
 

Offline MikeS

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Is this the cause of cosmological expansion?
« Reply #5 on: 10/08/2011 08:22:36 »
"But observations of distant type Ia supernovae place them significantly farther away than would be expected from their redshifts,"
http://www.lbl.gov/supernova/

The standard model attempts to explain this by invoking hypothetical 'dark energy'.  It can be more simply explained by time dilation in the past.

The cosmic microwave background radiation is often quoted as evidence that the universe is expanding but is equally evidence that time was dilated in the past.

As cosmological red-shift and standard candles are two of the main indicators of an expanding universe and we can see that either one or the other is wrong and add this to the CBR which could be interpreted as time dilation/contraction then it does rather make a mockery of our knowledge on the subject.

Is this evidence that the universe is expanding?  Well, it could be but it is equally evidence that time was dilated in the past.  It seems probable to me that the observed cosmological red-shift is a mixture of the Hubble constant and time dilation/contraction.

To sum up:-
The cosmological red-shift
Type 1a supernova discrepancy as standard candles
The CBR
These can all be explained by clocks running slower in the past and (the discrepancy) of type 1a supernova as standard candles is evidence that clocks actually were running slower in the past. 

« Last Edit: 24/08/2011 08:48:30 by MikeS »
 

Offline MikeS

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Is this the cause of cosmological expansion?
« Reply #6 on: 17/08/2011 08:07:47 »
Olbers' Paradox
http://en.wikipedia.org/wiki/Olbers'_paradox

Olbers' Paradox is sometimes quoted as evidence of the universe expanding but this explanation has been disproved by Edward Robert Harrison.
http://en.wikipedia.org/wiki/Edward_Robert_Harrison
« Last Edit: 17/08/2011 08:11:34 by MikeS »
 

Offline MikeS

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Is this the cause of cosmological expansion?
« Reply #7 on: 27/08/2011 10:10:27 »
Question: Is it at all possible for red shift to be caused by something other than expansion? And if so, how would this act as a barrier to hide the far reaches of the Universe, or the edge?
http://www.thenakedscientists.com/forum/index.php?topic=39703.msg365885#msg365885

Red-shift caused by time dilation in the past or time contraction now would appear the same as red-shift by expansion.  The reasons are listed below.

1)   Time dilation by gravity is a known and proven fact.  (in as much as physics can allow facts)
2)   There is no reason to suspect that cosmological time is and always has been a constant.
3)   Gravity dilates time therefore; if gravity was stronger in the past cosmological time would have been dilated.
4)   When the universe was young, after the formation of hydrogen and helium but before stars formed, it was dominated by matter.  Therefore, gravity would have been stronger and time dilated.
5)   Since stars ignited, there has been a continuous conversion of matter (mass) into energy.  Matter within the Universe is decreasing therefore gravity is becoming weaker.  It follows that time must be contracting.
6)   The contraction of time whilst the universe is in the fuel burning stage is continuous.  Therefore, time contraction is progressive and continuous.
7)   Continuous time contraction looks the same as cosmological expansion and it would give the illusion that expansion is accelerating. “It would act as a barrier to hide the far reaches of the universe” in exactly the same way that cosmological expansion does.

Quite obviously the universe has expanded in the past.  Whether it is still expanding and whether that expansion is increasing is another matter. 
« Last Edit: 27/08/2011 10:24:53 by MikeS »
 

Offline Robro

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Is this the cause of cosmological expansion?
« Reply #8 on: 29/08/2011 15:11:08 »
@ Mike S

Wow! This is an interesting concept and requires thought in many directions. But I'm not sure if the time dilation principle works for the universe as a whole as it seems it would be a localized effect around gravity fields. Perhaps there is the overall effect of time-entropy. Time running faster as entropy increases. As black holes evaporate, they would release their hold on time as their entropy increases. As the Universe gets older, time runs faster as the overall entropy of the Universe would have increased. Very interesting, I need more "Time" to fully wrap my head around this one. :)
 

Offline MikeS

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Is this the cause of cosmological expansion?
« Reply #9 on: 31/08/2011 07:28:50 »
Rob

To answer the first part of your query.

Everywhere in the Universe, there is gravity so there must be a universal average gravitational field and that average equates to a particular time dilation.  Mass causes gravity and dilates time.  If the mass of the Universe is being converted into energy, which it is in stars then the average gravitational field in the universe, must be weakening and time contracting.  There is no reason to assume that cosmological time is and always has been constant.

I will get back to you on the part about entropy.
« Last Edit: 31/08/2011 10:26:07 by MikeS »
 

Offline MikeS

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Is this the cause of cosmological expansion?
« Reply #10 on: 31/08/2011 10:07:17 »
Rob

Entropy

Whilst the Universe is in the star burning phase mass is being converted into energy so its relative mass is decreasing.  Time is contracting.  This says little about entropy as energy is being produced.  One may be balancing the other.  This energy (photon pressure) may be the repulsive ‘force’ causing the Universe to expand.  Ultimately, the stars will die as they run out of fuel.  Entropy will increase.   So overall, time has run faster as entropy increases but it may be that entropy does not increase (in the universe as a whole) until the production of energy ceases.  As you mentioned “time runs faster as entropy increases” and time runs faster as the overall entropy of the Universe would have increased”.  This is true only up to the point where the Universe is at its maximum size, which is also its maximum energy/mass ratio

If the universe is ‘open’ then it will continue to expand forever and entropy will increase towards infinity.

If the universe is (gravitationally) closed then we might expect entropy to reverse but this would be wrong as black holes absorb both mass and energy (all space-time geodesics end in a singularity).  The energy/mass ratio reverses and time dilates.  As black hole devours black hole time continues to dilate.  Entropy is increasing but time is running slower.
The changing energy/mass ratio or time dilating/contracting are not in themselves arrows of time.


Tying it all together, we get-

Gravity is the deformation of space-time by mass in trying to:-
1)   reach the highest gravitational potential
2)   reach the lowest energy level
3)   reach the highest entropy level
4)   reduce the universe to its minimum size 
5)   reduce the passage of time to a minimum

There are two main arrows of time, gravity and entropy.

As I like to think of it.  The arrow of time is pointing towards the black hole at the end of the universe.
« Last Edit: 31/08/2011 10:33:53 by MikeS »
 

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Is this the cause of cosmological expansion?
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