Flat Closed or open universe whats your thoughts?

Question

OK so lets say the universe is expanding forever. It reaches a point where everything that exists is really really small particals of mater that no longer come into contact with each other physicaly. Would these objects keep on spreading farther apart or would for some reason unknown to me start to come back together? If they keep expanding away from each other is it possible that they would reach a point where they would become unstable and break apart/explode like the big bang only smaller then the one before it?

Answer 1

Before dark energy was "discovered" the most popular theory was that the universe was flat, so it would stop expanding in infinite time. Since dark energy all bets are off - there are theories that the universe will tear itself apart in a "big rip"

Answer 2

The universe is finite but expanding. Recent studies show that the expansion of the universe may be speeding up. If so we will eventually reach a state called heat death where everything has the same temperature.

Answer 3

the universe has only been expanding since the big bang, before that it was all coming together into a big black hole.
eventually the black hole will win and collect all the stuff and explode again.
then we have to start all over, so save your notes.

Answer 4

big bang, galaxies are spreading out and expanding, until gravity's pull forces them to contract and come together again (Big Crunch)---explode another Big Bang and outward expansion ad infinitum

Answer 5

the universe does expand forever, according to hubble.
we know this to be true because of the redshifts that stars emit

Answer 6

Wherever you are, there you are and you can always move just a bit further so I'm all for the ever expandingness of emptyness.

Answer 7

oh i don't know, if someone figures it out, that's awesome, but I don't care that much