I think that at this point we should clear up some terms and theories that are being consistantly misused.
1: Dimentions: a Dimention in NOT a paralell universe I can't remember how many times I have heard this term misused. A dimention is a sort of discription of an objects possible movemnet. In our univerese we know we have (at least) 3 spatial dimetions ( the "forward backward" dimention, the "up and down dimention", and the "side to side" dimention) and 1 time dimention (and it appears we can only move forward through it).
2: Paralell universe: Possible paralell universes may have the same or a different number of dimentions. This actualy adresses what this thread was supposed to be talking about.
Lee Smolin has a theory that what preceeded the big bang may have been a black hole in a paralell universe. When a black hole is created there is a breif period where it sucks in space and creates a second distinct and seprate universe (so the theory goes) this seprate universe has it's own laws of physics that may, or may not, be slightly or grossly different from those of it's parent universe. The more likely a new universe is to produce black holes the more "daughter universes" it creates. So that universes can "evolve" in the same way organisms do. This is all very speculative I might add.
3: The "Crash-Bang" theory: Modern cosmology does NOT predict that the universe will recolapse. Instead we were suprised to learn that the univerese is accclerating it's expansion. The "Big Crunch theory" is well on it's way out.
4: The "two branes" theory: There IS a proposed theory for a cyclical universe that proposes that our universe and a nearby parallell universe are connected by "strings" and are locked in a cycle of collitions, each time the universes collide a big bang is produced. This theory is consistant with inflationary cosmology witch predicts a much more rapid expantion of space moments after the big bang than was previously predicted (this is a hot topic right now (and by this I mean infaltionary cosmology)).
So there you go hopefully this can both clean up our terminology and advance the discussion of what came "before" the big bang.
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