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Author Topic: Universe: To be or not to be infinity?  (Read 13437 times)

Offline qpan

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Re: Universe: To be or not to be infinity?
« Reply #25 on: 31/03/2004 23:21:57 »
If the universe is infinite in size, the universe will reach maximum entropy (equilibrium) when time = infinity. It is not possible to have finite entropy in an infinite universe. Maximum entropy occurs when the whole universe is filled up with an equal density of matter, but if the universe is infinite, matter needs to expand forever to reach equilibrium.
However, if the universe ends in a big crunch, then the maximum achievable entropy will be at the end of the big crunch when the universe is just 1 superheavy black hole/singularity (as black holes have very high values of entropy).

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Offline tweener

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Re: Universe: To be or not to be infinity?
« Reply #26 on: 01/04/2004 02:48:49 »
If you believe M-theory, it appears that black holes are actually massless. [?][?][?]

So, I guess that means that if the big crunch comes, then the universe will be one 3-brane wrapped around a massless singularity in a very small 11-dimensional universe. Then what?

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Offline qpan

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Re: Universe: To be or not to be infinity?
« Reply #27 on: 01/04/2004 13:50:35 »
quote:
Originally posted by tweener


So, I guess that means that if the big crunch comes, then the universe will be one 3-brane wrapped around a massless singularity in a very small 11-dimensional universe. Then what?

----
John - The Eternal Pessimist.



Then maybe the big bang will occur again! (or maybe that will be the end of "everything," at least in our space-time)

And yep- black holes do appear to be massless in some forms of M-theory...Very strange if you ask me!

"I have great faith in fools; self-confidence my friends call it."
-Edgar Allan Poe
 

Offline tweener

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Re: Universe: To be or not to be infinity?
« Reply #28 on: 01/04/2004 16:09:30 »
Or, maybe our universe is a singularity that is wrapped by some p-brane inside another universe?  That means the "big bang" was the spatial tear that made the singularity and the big crunch is the "repair" of the singularity that string theory predicts will happen.  Then what?

----
John - The Eternal Pessimist.
 

Offline qpan

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Re: Universe: To be or not to be infinity?
« Reply #29 on: 31/03/2004 23:21:57 »
If the universe is infinite in size, the universe will reach maximum entropy (equilibrium) when time = infinity. It is not possible to have finite entropy in an infinite universe. Maximum entropy occurs when the whole universe is filled up with an equal density of matter, but if the universe is infinite, matter needs to expand forever to reach equilibrium.
However, if the universe ends in a big crunch, then the maximum achievable entropy will be at the end of the big crunch when the universe is just 1 superheavy black hole/singularity (as black holes have very high values of entropy).

"I have great faith in fools; self-confidence my friends call it."
-Edgar Allan Poe
 

Offline tweener

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Re: Universe: To be or not to be infinity?
« Reply #30 on: 01/04/2004 02:48:49 »
If you believe M-theory, it appears that black holes are actually massless. [?][?][?]

So, I guess that means that if the big crunch comes, then the universe will be one 3-brane wrapped around a massless singularity in a very small 11-dimensional universe. Then what?

----
John - The Eternal Pessimist.
 

Offline qpan

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Re: Universe: To be or not to be infinity?
« Reply #31 on: 01/04/2004 13:50:35 »
quote:
Originally posted by tweener


So, I guess that means that if the big crunch comes, then the universe will be one 3-brane wrapped around a massless singularity in a very small 11-dimensional universe. Then what?

----
John - The Eternal Pessimist.



Then maybe the big bang will occur again! (or maybe that will be the end of "everything," at least in our space-time)

And yep- black holes do appear to be massless in some forms of M-theory...Very strange if you ask me!

"I have great faith in fools; self-confidence my friends call it."
-Edgar Allan Poe
 

Offline tweener

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Re: Universe: To be or not to be infinity?
« Reply #32 on: 01/04/2004 16:09:30 »
Or, maybe our universe is a singularity that is wrapped by some p-brane inside another universe?  That means the "big bang" was the spatial tear that made the singularity and the big crunch is the "repair" of the singularity that string theory predicts will happen.  Then what?

----
John - The Eternal Pessimist.
 

Offline neilep

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Re: Universe: To be or not to be infinity?
« Reply #33 on: 19/04/2004 18:08:42 »
Phew !!!..I'm exhausetd after reading and attempting to digest all this info...but I can't help but be completely mesmerised by it all, it's absolutely fascinating stuff !!........I'm sure if there is an edge to the Universe then somewhere on the other side there is probably a Macky Dees doing quite well !!:D They seem to pop up everywhere don't they ?

Sorry for lowering the tone !![:o)]

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Re: Universe: To be or not to be infinity?
« Reply #33 on: 19/04/2004 18:08:42 »

 

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