Reverse process of Universe?

Question

In a closed universe, the universe collapses and heats up - sort of the big bang in reverse. Describe what happens to atoms as the temperature heats up.

My answer

I think that the atoms would move fast constant till they die?

Answer 1

First of all, the universe is expanding at an accelerating rate; your question makes no sense. Secondly, at the higher energies, atoms would decompose.