ReKleSS wrote:The Coop wrote:Many years back, I took to heart the idea that our blob of matter, stars and galaxies is the known universe, which is surrounded by the unknown universe. There may or may not be anything outside the edges of our "blob of stuff", but it's expanding into something. And that something, is also part of the universe.
I suspect this idea is not correct. I don't think it's possible to really comprehend the concept that there's nothing outside it... compare it with time and the big bang (i.e. nothing before t=0). Also, there are theories that the universe is toroidal (think Asteroids), which might make it easier...
A few years ago, people thought the space between the stars was empty except for some dust or gas. Now we have dark matter theories flying about. I don't think it's that hard to comprehend that everything created by our Big Bang (assuming you believe in it in the first place) is expanding into something that we haven't discovered yet (or have we without knowing it?).
By nature, the Big Bang theory suggests that there was a time when all we've seen and discovered thus far wasn't here. Our present definition of time began at that moment, and our current concepts of matter did as well. And even within the confines of the Big Bang, there are speeds, temperatures and events so violent, that people may have a hard time comprehending them... yet they're handily accepted. Science can't explain just what happens inside a black hole, because all our current math and physics breaks down at the singularity (collapse of space-time geometry as some call it)... but we know an event does indeed happen. As such, it shouldn't be tough to envision that there's something outside of all our "stuff", which is being encroached upon. I simply can not accept that if you were to somehow reach the edge of everything expanding from our Big Bang, that you'd simply hit an impenetrable wall (for that lack of a better phrasing) that can not be moved past.
I know people like to say that nothing was here before the Big Bang, but something caused it. And whatever caused it was surrounded by something (and created by something for that matter). Whatever that something was, is quite possibly still residing outside of our known universe (which would be the "unknown universe" that I referred to before).
Again, these are just my thoughts on all this, even if I don't have the mathematics, physics, or in-depth science background to back it up.
Edit: Minor clean up.
google video is great if you want to watch full-length cosmology lectures on the subject 
