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NASA: Evidence Favors Infinitely Expanding Universe
Chris Gondek writes "The Sydney Morning Herald has a story here about how NASA is expected to announce this week that it has proved the existence of "dark energy," a cosmic force that counteracts gravity and will keep the universe expanding forever. The announcement will effectively demolish the theory that life will be wiped out in a "big crunch" when the universe collapses, and should end decades of academic dispute. Scientists ranging from Stephen Hawking, the Cambridge University physicist, to Albert Einstein, have argued that the universe eventually will stop expanding and then implode under the force of gravity, destroying all life. The Chicago Sun Times has also got some info."
Well, I'm no astophysicist, but won't this new theory disprove all previous theories about the Bing Bang as well, and everything we thing of the Universe thus far. If this susbstance will keep the Universe expanding forever, how was it ever possible to have a Big Bang in the first place? It would be inconcievable to think anything created the Universe in the Big Bang theory, because it could never happen, thus our Universe does not go in cycles (expand then contract - repeat).
So, How did the universe get created. Does this mean that there was actually a "beginning of time" as far as we can tell? What was that point? What existed before then? Since matter can't be created nor destroyed, where did it come from? (though that is a question beyond most planes of though, IMO)
I don't believe this story, and I think more research is needed here.
"Time is long and life is short, so begin to live while you still can." -EV
You got it, though "wiped out" isn't really the term I'd use (more like "stretched out"). It lowers the heat death temperature so that it approaches absolute zero, since the space occupied would constantly expand. Also, it's a rather lonely future even before then, as galaxies grow so far apart that you eventually can't see anything but your own big front yard.
I wouldn't get too excited, though. There are virtually no "facts" in cosmology that haven't been overthrown multiple times. This one will be no different.
Why? It's just as good a term as Einstein's cosmological constant. It's just a label.
And the "blackbox" approach is part of figuring out what is going on. We don't know how gravity works. Does that stop us from knowing that it does work, or what effects it has on the universe? This is no different.
If we had to wait until we had a nuts-and-bolts answer for every question we'd never get anywhere.
Boobies never hurt anyone. - Sherry Glaser.
According to the best cosmological theory we have now:
The universe came into being. At first, there was but one force. As the universe grew larger and colder, aspects of that one force that were hidden became apparent - these are the forces we know of now: gravity, electroweak, strong nuclear.
Consider:
Trillions of years from now, the universe is much larger and colder. Aspects of the four forces we know of now become apparent, creating new forces.
Who is to say that in a google of years, there won't be some lifeform that will look back and say (translating to English) "We aren't sure what happened in the first trillion years, but after that, the 27 forces of nature we know of began to manefest themselves..."
Who is to say that there was not some lifeform living at the first 10e-32 second that was looking forward and saying (translating into English) "One day, seconds from now, all life as we know it will cease, and the universe will be far too cold to support life."
www.eFax.com are spammers
Also remember that no one has been looking to see if energy is added or removed from the universe. All of these theories are based on the notion of a closed system. What if that assumption was not true?
"Learning is not compulsory... neither is survival."
--Dr.W.Edwards Deming
Are you talking about how there is no global energy conservation due to time assymetry and Noether's theorem?
I find this an interesting fate because it's also reflected in some religions and philosophies, where everything becomes one at the end of time.
Don't most religions postulating "one" at the end of time actually have something closer to the big-bang / big-crunch? I mean the final conflagration in Heraclitus on up through the Stoics seems to have much more in common with the earlier view of cosmology. The big cruch returns everything to fire = logos that was had at the beginning of the universe. In this view the fire is raw energy and information.
I don't know of anything in traditional philosophies or religions that really corresponds to the heat death of the universe.
Think of it this way, the thing that is slowing down the expansion of the universe is the gravity within the universe pulling inwards. If there's enough gravity to overcome the energy of the big-bang....the big crunch happens. However since gravity decreases as the universe expande (because of the inverse square stuff) if the univers gets too large there's a point where it's graivty is no longer sufficient to turn expansion around. (And yes there's this the theory of the "sweet spot" where the energy and the mass are perectly ballanced and the universe stops expanding but fails to colapse. The rate of expansion IS decreasing, the question is will that be enough to cause the crunsh or not because the rate of decrease (second derivitie of velocity) is decreasing as well.
I think that Buddhist Nirvana sort of does; entities that become enlightened are never returned to the wheel of life, so there's a constant drain of energy "lost" by the world to nothingness. The peace of Nirvana always seemed something like a perfectly uniform universe to me. Eventually everyone on every plane is enlightened and everything is just sort of frozen (which is a way of looking at heat death, complete equilibrium being equivalent to no motion at all).
On the other hand Taoism would propose a universe that expands back into the original version of itself, since everything proceeds through an extreme, into and through its opposite, and back into itself. That's broad enough that you could fit either a big-bang-big-crunch, or a heat death where something about the uniform state causes the return of extreme nonuniformity (which is entirely possible, see below).
One of the things I find provocative about the heat death and "big egg" fates is that they're at some level indistinguishable. Once the universe is uniform, both time and space becomes meaningless, just as they do after a big crunch. So the Taoist view makes sense to me - the universe really does find its opposite (and a rebirth) at the extreme ends of time.
Oh well. I really have things I should be doing today besides discussing cosmology, if I'm to be able to afford to keep converting free energy myself. ;)