The Expanding Universe

Michael and I have begun watching Stephen Hawking's Universe, and I found myself dreaming about universes in the shapes of balloons and brains last night, after our conversation about the universe expanding last night.

I had a hard time not viewing the universe as finite, if it's continually expanding. Michael explained it as though we're fish swimming in an ox-bow of a river. We simply can't see how close one point of the river is to the continuing main stream of the river where it's close, and all the fish sees is that the distant point is far away. Michael thinks it's not all linear, due to gravity, and that it sort of bends back and twists upon itself.

He brought up the concept of the wormhole, and he suggested the analogy of the river developing a direct opening to the straight-away of the river, eliminating the ox-bow portion. I'm still trying to wrap my brain around it, but he suggested there would be a point of a huge release of energy, when the river finally fully burst forth to it's straight-away connection.
Anyhow, it made me wonder if that might be a causation of the Big Bang. Maybe our 'universe' really is a discreet entity that we can't see out of, and the explosion sort of is our universe's 'beginning', as it wiped out all else before it? Was the Big Bang an exploding wormhole from another universe?

Don't listen to me! I know nothing about all this stuff, and I've never felt quite so amazed as when I took a physical chemistry class and was introduced to quantum physics. My brain could simply not completely understand the concepts, but I would struggle and get a partial understanding that meant re-defining my concept of reality. My glimpse into quantum mechanics left me amazed and humble.

I am not beyond believing that there are other dimensions, other realities, that share the same finite space within which we exist. Perhaps they exist in the 'dark matter' that we can't see or detect except for the fact that we can measure its indirect influence in ways. We can only see a limited range of wavelengths...how many more possibilities are there?

I believe we have a few more shows in the series, so I may wax on about this subject for a while!