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Larspeart
7th March 2003, 09:38 AM
Anyone care to explain this theory, and whether it holds much weight?

http://www.space.com/scienceastronomy/big_rip_030306.html
SFB
7th March 2003, 11:08 AM
Originally posted by Larspeart
Anyone care to explain this theory, and whether it holds much weight?

http://www.space.com/scienceastronomy/big_rip_030306.html

I certainly don't have the background to lend weight to the article but this sentence annoyed me:

"Scientifically it is just about the most repulsive notion ever conceived."
7th March 2003, 11:21 AM
"out-of-control phantom energy"


LOL.

That about covers it.

:)
fishbob
7th March 2003, 11:53 AM
It is not theory yet. It appears to be a hypothesis based on the output of computer models.
DanishDynamite
7th March 2003, 12:18 PM
Interesting article, Larspeart.

While I'm no expert, it seems to be a straight forward consequence of tinkering with the cosmological constant. If it grows with time, the acceleration of space expanding will itself accelerate. Obviously, if an epansionary force (previously only significant at intergalactic scales) keeps growing, it will at some point start ripping up local stuff as well.

At the moment, however, it is just speculative tinkering, as far as I understand the article. Of course, as with any scientific hypothisis, it makes predictions which can then be tested.
rwald
7th March 2003, 02:32 PM
Interesting article. I wonder how an accelerating acceleration would allow for stable wormholes? (Since time travel is a direct consequence of stable wormholes, I won't bother asking about it.) Maybe something to do with negative energy...
Larspeart
11th March 2003, 10:05 AM
Hmm, good points. I guess it 'could' happen. Interesting appraoch to the idea of expansion in the cosmos.

Anyway, there was a small update/addition to the original article on this.

http://www.space.com/astronotes/astronotes.html


It seems that a LOT of scienctists are puzzled and/or curious about this theory/hypo. Hell, even the responder at Space.com is at a loss for detailed answers to give on it.

What do you all think? Agree? Disagree? Curious? Skeptical?
DanishDynamite
11th March 2003, 01:08 PM
Larspeart:What do you all think? Agree? Disagree? Curious? Skeptical? Well, offhand I'm skeptical because this tinkering isn't a solution to any known problem. It is just fiddling with a "constant" and extrapolating.

It would be a bit like me postulating that the gravitational constant grows by one part in a trillion, every trillion years. Could that be true? Yes. Is there any reason to think so? No. Is there any evidence for or against? No.