The "Big Bang theory" is a theory on how the world was created. This model describes how the universe expanded from a very high density and high temperature state (and is continually expanding). Scientists are still not sure where the big bang began, and do not know how to even describe it at times. After the expansion, the universe cooled enough to allow the formation of sub-atoms. In 1927, Georges Lemaitre stated that the universe can be traced to a central point, and today scientists are trying to find that point. There is however, still not enough evidence and information on the big bang, and since it still cannot be proven adequately enough, it is still considered a theory, and not a law.
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