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* It has begun like a "Big Bang," a huge explosion. It has had an inflationary phase, one of rapid expansion, before the apparition of gravity, and, possibly before the apparition of the strong nuclear force. It is still expanding at a fairly constant rate that makes close to the limit of a closed universe or an open one. If it is the former, it can contract and involute or even rebound again. If it is the latter, it can be flat, its only way to keep its matter together. Furthermore, there might be parrallel universes, but till now the evidence makes it one.