If the Universe is expanding, what is it expanding into? And what did the Big Bang expand into before the Universe was there?
Puck: Surely, they must both be expanding into the same whateveritis?
Sniffy: Yes, but what is it?
The Thoughts & Ramblings of a Growing Man
If the Universe is expanding, what is it expanding into? And what did the Big Bang expand into before the Universe was there?