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View Full Version : Big Bang's final moments



darkdev
2004-Apr-15, 04:00 AM
If the universe is truely expanding (as it cools), what happens at the end of this process?

To me, this implies that at some point in time, the universe and everything in it will reach Zero Kelvin. If so, what then, that doesn't mean it fades from existance, right?

Can massive Black Holes be the answer? Is it possible for a BH to resist something like the "Big Rip (http://www.badastronomy.com/phpBB/viewtopic.php?t=12815&highlight=big%20rip)"?

PhantomWolf
2004-Apr-15, 04:04 AM
The evidences that the universe is acclerating apart seem pretty solid, so if that continues we'll eventually get to the point where the rest of the universe it too far away for the light to be able to get here, resulting in a number of mini universes and so on. I suppose that given long enough it could result in a universe containing only the Milky Way, but rewally I don't see it ever just vanishing, nor reversing and going crunch.

darkdev
2004-Apr-15, 04:08 AM
I suppose that given long enough it could result in a universe containing only the Milky Way, but rewally I don't see it ever just vanishing, nor reversing and going crunch.
Are you saying the Milky Way will last that long. After 100 billion years the Solar System will be long gone, as we know it at least.

What is the fate of our mini universe?

PhantomWolf
2004-Apr-15, 04:20 AM
Well if things really do go that way, who knows, perhaps the gases from the dead stars will reform into new ones and the whole thing will restart. I guess we'll have to wait around for a few billion years to find out. ;)

Mokele Mbembe
2004-Apr-15, 05:36 AM
I'm not entirely sure what will happen, but if you are seriously interested in this topic and have not yet read The Five Ages of the Universe by Fred Adams... do so.

I liked it, at least.

Kaptain K
2004-Apr-15, 12:15 PM
If the "Big Rip" hypothesis is correct, in approximately 30 billion years, the universe will be expanding so fast (and the speed accelerating so much) that it will tear apart not only galaxies, but stars, then planets, and on to atoms, elementary particles and even quarks. At which point, time itself ends!

Dgennero
2004-Apr-15, 02:38 PM
I know that my favorite theory of a cyclic universe (big bang --- expansion --- contraction --- big crunch ---- big bang...) is losing probability in the light of the newest findings, but I stick to it till it is absolutely sure that this cannot happen.
Reason: It explains our existence neatly IMO, because if we have an infinite number of universes, again and again, everything with a probability greater than zero will eventually happen.

But it might also be possible that our universe is just a tiny bubble within a bigger structure, spawned off by some insignificant event 8)

George
2004-Apr-15, 02:48 PM
M-brane theory is intriguing to me. There is a chance our accelerated expansion is due to an approaching brane.

Normandy6644
2004-Apr-15, 02:54 PM
I know that my favorite theory of a cyclic universe (big bang --- expansion --- contraction --- big crunch ---- big bang...) is losing probability in the light of the newest findings, but I stick to it till it is absolutely sure that this cannot happen.
Reason: It explains our existence neatly IMO, because if we have an infinite number of universes, again and again, everything with a probability greater than zero will eventually happen.

But it might also be possible that our universe is just a tiny bubble within a bigger structure, spawned off by some insignificant event 8)

I go with that as well. it just seems so cool that you have to like it, even if you don't quite buy it yet.

Jerry
2004-Apr-15, 03:02 PM
Not even close. (please post theory) - How do I vote on this? It is tough being billboard challenged.

Theory? When I dug into the supernovae data and realized everything I thought I knew about the universe was wrong, I felt like a kid who had just discovered there is no Santa.
http://arxiv.org/abs/astro-ph/0404207

iFire
2004-Apr-15, 03:26 PM
Theres no Santa? :o :P

I think that its just going to like... stop... :roll:

darkdev
2004-Apr-15, 05:06 PM
Theory? When I dug into the supernovae data and realized everything I thought I knew about the universe was wrong, I felt like a kid who had just discovered there is no Santa.
Theory, in essence, means no-one knows. The way I like to look at it is that at best, you can have a good "feel" for things. In the short time I've spent participating in conversations on this board I have definately been corrected and some thoughts clarified, I feel somewhat smarter 8-[ , but have also been reminded that everything I think I know is just that... what I think I know.

So far I like:
If the "Big Rip" hypothesis is correct, in approximately 30 billion years, the universe will be expanding so fast (and the speed accelerating so much) that it will tear apart not only galaxies, but stars, then planets, and on to atoms, elementary particles and even quarks. At which point, time itself ends!
...but with a slightly different conclusion. It has been said that forces between quarks increase over distance, so if quarks are ripped apart, a tremendous amount of energy will be created "in the force plane", and may infact generate another (or many) big bangs. With this in mind, maybe our big bang is only one of many continually generated as previous bangs expand into oblivion.

"Time can't end, it never started." ???

Also intriguing:
Reason: It explains our existence neatly IMO, because if we have an infinite number of universes, again and again, everything with a probability greater than zero will eventually happen.
I like it, but the major problem I see is our calculation of probability, which is likely to be oh-so-flawed. I saw this on a cool PBS special about string theory (http://www.pbs.org/wgbh/nova/elegant/program.html) (it's a little long winded and slow, but cool none the less):

The problem with algebra:

X=YZ, seems okay, Y can be any number.

now, apply some mathematical transformation....

Z=X/Y, well, now Y can't be Zero!

We went from Y can be anything to Y can't be 0 just by shifting the perspective.