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Author Topic: Can Minkowski diagrams show us the fate of the universe?  (Read 1322 times)

Offline jeffreyH

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I would think that using minkowski diagrams with the hubble data and then plotting this forward so it represents an instantaneous picture of the current positions of galaxies could show us the expected fate of the universe. Would this indicate that some galaxies have already crossed the hubble sphere and are outside the observable universe?


 

Offline PmbPhy

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Re: Can Minkowski diagrams show us the fate of the universe?
« Reply #1 on: 02/07/2014 11:44:02 »
I would think that using minkowski diagrams with the hubble data and then plotting this forward so it represents an instantaneous picture of the current positions of galaxies could show us the expected fate of the universe. Would this indicate that some galaxies have already crossed the hubble sphere and are outside the observable universe?
Hard to say. We can take guesses though. Look at what happened during the last decade when it became known that the universe is expanding at an accelerating rate. Right now we don't know the densities of the various forms of matter to enough precision to determine the result in he distant future.
 

Offline jccc

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Re: Can Minkowski diagrams show us the fate of the universe?
« Reply #2 on: 02/07/2014 22:39:14 »
Our detecting power is so so, how do we know what's out side of what we already know?

If part of the universe is expending >= C away from us, we should never find it. But it could be there.
 

Offline jeffreyH

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Re: Can Minkowski diagrams show us the fate of the universe?
« Reply #3 on: 02/07/2014 23:22:45 »
I would think that using minkowski diagrams with the hubble data and then plotting this forward so it represents an instantaneous picture of the current positions of galaxies could show us the expected fate of the universe. Would this indicate that some galaxies have already crossed the hubble sphere and are outside the observable universe?
Hard to say. We can take guesses though. Look at what happened during the last decade when it became known that the universe is expanding at an accelerating rate. Right now we don't know the densities of the various forms of matter to enough precision to determine the result in he distant future.

Minkowski space-time would be inaccurate as it would not cope easily with gravitational effects anyway.
 

Offline jeffreyH

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Re: Can Minkowski diagrams show us the fate of the universe?
« Reply #4 on: 02/07/2014 23:42:48 »
There is also an amount of light that is lost from the observable universe by falling into black holes. This should also be happening at the horizon of the hubble sphere. Photons are considered as massless but have energy. Therefore the total energy content within the bounds of the observable universe must be decreasing by a particular factor over time. Due to e=mc^2 we can also deduce that this will also be equivalent to a mass loss. Therefore can we ever determine a mass density in such a dynamically changing system?. The light crossing the hubble sphere cannot exceed c as far as our view of physics tells us. This indicates that the light cone outside this sphere operates in a different way. This may be related in some way to the reversal of the light cone inside the event horizon of black holes.
I would hazard a guess that mathematically the hubble horizon would be indistinguishable from the horizon of a white hole.
« Last Edit: 02/07/2014 23:49:03 by jeffreyH »
 

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Re: Can Minkowski diagrams show us the fate of the universe?
« Reply #4 on: 02/07/2014 23:42:48 »

 

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