How will the Universe end?

Mar22-03, 11:05 AM

What do you think will happen to the Universe? How long will it be until it ends? or will it go on expanding for ever?

**marcus** · Mar22-03, 01:14 PM

hello parsons, this year the big news about the fate of the universe seems to be the MAP (microwave anisotropy probe) results and there seems to be a convergence of opinion
around things like

flat
runaway expansion
hubbleparameter 71 in the usual units
darkenergy comprising some 73 percent of density (!)
darkmatter and ordinary matter some 27 percent

a good place to find out is at Ned Wright's cosmology tutorial site that also has an interesting cosmology FAQ
on the introductory page he has "news of the universe"
with a lot of the latest results, like MAP, which came out
in february of this year (!)

MAP is an incredibly elegant observer based at the L2 point
a million miles out from the earth along the sun-earth line.
that way the earth shields MAP from the light of the sun

this kind of thing together with HST and keck are just totally revolutionizing cosmology. when you say "Flat Model" do you mean flat with vacuum contributing 73 percent or zero percent? it seems to make a considerable difference.

Mar22-03, 09:27 PM

I chose the Big Crunch. I have read reports of a "Great Attractor" that is causing galaxies to gather into one spot. I heard this from a 5 hour long Discovery Channel documentary on cosmic inflation.
And also, the static universe thing should kick in sometime![:D]

**Zefram** · Mar22-03, 10:33 PM

I'm going to go out on a limb and say Big Rip; c'mon dark energy!

Mar22-03, 10:39 PM

Originally posted by Sensei
Why assume it will end? even in a big crunch... there may be repeat cyclings to the big bang again > big crunch > big bang > big crunch sequence.

If we lived long enough to witness the big crunch (if it happened) i wonder if we could survive by hiding temporarily in a fourth or fifth dimension...

hmm... too many questions, such little technology.

Yes, I have considered the cycle it will create. But you have to admit that there are several versions of cycles in this universe. Furthermore, the fifth demension+ will be effected too. After all, such a demension is a "curled" demension. As Stephen Hawking puts it: if you look at a single hair, it appears to be only 1D. But, when you magnify it, the single hair is composed of 3D molecules. It has demension, and the demension is viewed through a variable magnification.

Mar22-03, 10:40 PM

Originally posted by Zefram
I'm going to go out on a limb and say Big Rip; c'mon dark energy!

Isn't the big rip the same as the big crunch?

**Zefram** · Mar22-03, 10:43 PM

No, the Big Rip is the result of the expansion of the universe continuing to accelerate until eventually everything in the universe is literally ripped apart. The exact opposite of the crunch.

Mar22-03, 10:46 PM

SH says we'd need a particle accelerator(i think it was, if not, it must be an electronmicroscope) the size of this solar system in order to view these demensions. Do you think that's even feasible? could that be accomplised, the building of such an instrument?

Mar22-03, 10:47 PM

Originally posted by Zefram
No, the Big Rip is the result of the expansion of the universe continuing to accelerate until eventually everything in the universe is literally ripped apart. The exact opposite of the crunch.

That doesn't make sense to me. Why do you believe it is tenable?

**Zefram** · Mar22-03, 10:49 PM

the dimensions, unlike the hair, may be subject to different laws than we are aware of at the moment.

Then the possibility exists that it might be very unhealthy to flee in them, don't you think?

**Zefram** · Mar22-03, 10:51 PM

Originally posted by MajinVegeta
That doesn't make sense to me. Why do you believe it is tenable?

Suppose the acceleration never ceases? I'm not saying it's necessarily the most likely end of it all but it's an interesting possibility.

Mar22-03, 10:54 PM

But what will it tear ? I believe it is taking the space-time fabric anology too literally. I find it evidently untenable. Does the theory implie an open universe?

**Zefram** · Mar22-03, 10:57 PM

Enjoy, Majin: space.com.

Mar22-03, 11:09 PM

I enjoyed the article. But it didn't make me change my mind about the big rip.

The first explosion

Caldwell's study had humble beginnings. He and his colleagues, Marc Kamionkowski and Nevin Weinberg at Caltech, were considering how a sphere of matter collapses under its own weight to form a galaxy. In computer models, they tweaked with the dark energy factor and found that too much of it would actually prevent the sphere from collapsing. In extreme cases, the sphere exploded.

This sounds a lot like the Big Crunch to me.

Secondly, what rips the matter apart? The dark matter or the phantom energy (is the phantom energy, since the article related it with the cosmological constant)?

**Turtle** · Mar23-03, 10:00 AM

There really is no "end". The universe is in an continual cycle.

Mar23-03, 02:16 PM

Yes, Turtle. The Big Crunch is in obvious favor of that.