Curious about the age of the Universe...

Drakkith

We have no idea if there are other dimensions. The only evidence we have is for 1 universe so far, so we definitely can't say that there are "probably" other dimensions. The age of the universe is approximately 13.6 billion years old.

Time travel isn't really believed to be possible by most professional scientists. And since we haven't observed it happening we can't say when we can do it and when we can't. Furthermore time travel is not allowed to be discussed per PF rules, as it very quickly gets out of hand since there are practically no rules regarding it. (Because it is an unobserved highly speculative subject that pretty much makes no sense)

Kraflyn

Hi.

There exist solutions for wormholes in general theory of relativity, theoretically only, of course, and those are unstable, at very tiny length scales, evaporate too quickly, require exotic matter and exotic effects, such as Casimir effect, to operate, and are not quite well established theoretically yet. There is a brief introduction to this subject on Wikipedia, of course, aimed at broader audience: http://en.wikipedia.org/wiki/Einstein-Rosen_Bridge. So, there isn't much to say, because of lack of full theoretical support, plus, we are very very far away from observing a wormhole experimentally.

Cheers.