Originally Posted by horatio
Like to the "if God is the prime mover who caused God?" question there is no answer to this matryoshka question.
Of course we imagine the universe like a ballon that is blown up but our imagination fails here. There is nothing outside of the universe so it is not expanding into anything. Our primate brains have not evolved to imagine this kind of stuff, that's why it will always be totally abstract.
It's like when theoretical physicists say that they cannot get their head around quantum mechanics. They might understand their model but not the phenomenon in and of itself. For us the very tiny and the very large break down into mathematical abstractions and are not really perceivable.
Exactly. The universe expands and what lies outside, what it is expanding into is completely beyond our comprehension. It's a question of existence. Existence is the universe and it is expanding and our 3 spatial dimensional minds perceive it is expanding into something but outside the universe there is not even anything, not even a void. There is no existence outside the perceivable universe.
A great and crazy question, Omega. Also Saq, some wonderful stuff you posted there.
To me, the whole question kinda reminds me of the end of the TNG episode 'Remember Me' where Crusher has been caught in a shrinking universe and everyone she knows is disappearing. At the end of the episode the known universe is collapsing in on the Enterprise and hull breaches are starting. You think of it as this bubble that's closing in on the ship and eventually will close in 'til there's nothing left, but when Crusher asks the ship computer the cause of the hull breaches, the computer responds that it's caused by flaws in the ship's design. It doesn't conceive of the ship that was there before the shrinking universe began to 'erase' portions of the ship from existence so it perceives the ship is built wrong. To me that touches on Omega's question. Outside the known universe there is not even a void or even 'nothing'. But some of the multiverse theories and quantum foam theories Saquist mentioned take a different angle on it.
It's crazy mind-boggling stuff. I'm still trying to get past that the behavior and state of matter on a subatomic level is defined by our perception of it. That's crazy, but true.