Go check out Through the Wormhole... Its a TV documentary series. Perhaps check out Season 2, Episode 2 - Is there an edge to the universe?

Doesn't really answer the question on what's beyond the universe or even whether there is an edge to the universe or is it perpetual, for lack of a better work . It's probably better if you watch it yourself. I am by no means an expert on this matter but I hope this little bit helps.

PS. good luck with your reserch!

Couldn't the universe also be shaped like a donut? mean if you folded a piece of paper into like a roll, and the join both ends of the roll, you'll get something shaped like a donut. It would fit the principles of expansion and a donut shaped universe would be perceived as infinite by it's in habitants. You'd just travel round and round... Then again, 46.6 billion light years is as far as we can see right now, so till science gets past that hurdle, I guess all we can do is imagine...

Sorry, what I meant was if you travel in a straight line, you'd in fact be going in circles... eg, draw a line on a piece of paper and then roll it up. An ant travelling on that line would think it's moving in a straight line. But in fact, the poor ant is just going around the rolled up peice of paper. Hence, giving it the illusion of an endless infinite space...

Bro, you an astrophysicist or what? Lol. Exactly what I was trying to say... Gotta admit you said it much better though. Finite but unbound, exactly. I was also trying to point out that the universe need not be in only the shape of a sphere to be finite but unbound. The donut a.k.a. hypersphere is merely another example of suach a shape...