Who Here Believes In An Alternate Universe? Why? What Do You Think Would Occur In Such A Place?

The idea of parallel universes makes a lot of sense. Unfortunately it's the type of idea that is very difficult to test. The History (or Discovery) channel had a decent program talking about it about 6 months ago. I have an "feeling" based on what I've read that it is plausible that there are infinite universes with new ones 'budding' at every quantum variation possible.

How can such a thing be tested though?

The concept of alternate universes is quite a novel one, however I don't believe they could exist.  The physical universe is bound by specific laws such that if you were to repeat the exact same scenario twice you could reasonably expect to see the exact same result which seems to suggest that there is a specific path our universe is headed down.

I don't know about alternate/parallel universes, but I do believe in multiple universes. Everything that we can observe and perceive, from the infinitesimal to the  colossal, behave in grouping patterns that make up part of a bigger whole. Planets and galaxies behave much in the same way that subatomic particles do, albeit for different reasons. I could see it being very plausible that the universe we live in makes up something much, much larger as well. It's kind of like Horton Hears a Who.