If the universe is expanding, then where is it expanding to? A previous void?

Answer 1

It's just expanding. The question of "where" it is expanding to cannot be answered because no one knows what is beyond the universe, and indeed, no one can know. The leading edge of the expanding universe would have to be the expanding light wave which is moving at the speed of light. Nothing can move faster than that so in order to move past it you would need to move faster than light to first catch up to it and then to move past it. This, says Einstein, is impossible, therefore no one can get access to information that is beyond the edge of the universe. The question is unanswerable.

Answer 2

outside of the universe, there is nothing, its very hard to imagine, but yes, it is expanding into a void. I dont think you should think that there is anything "outside" the universe, the edges of the universe are the ultimate boundary, but one cannot go to the "edge" of the universe, simply because it does not exist. My physics teacher put this down in a really nice way,
Take a balloon, draw two Xs, one representing you and the other a galaxy(or another object), blow up the balloon, you will see the galaxy moving away, but you are also on the outside of the sphere, therefore there is no edge to the universe, we must think in 4D, not 3D, as the fourth dimension we live in is time.

Answer 3

If you've seen Dr Who, it's a bit like if they interior of the TARDIS was getting bigger, but the outside stays the same size. The universe is only expanding into 'itself' if that makes sense. Space is something within the universe, the universe isn't in space.

Answer 4

every thing is void ,space and more space . The size of the universe is beyond any thing we can imagine. Thaveling for millions of light years and still no end.