IUPAC definition. polymerization: The process of converting a monomer or a mixture of monomers into a polymer. An example of alkene polymerization, in which each styrene monomer's double bond reforms as a single bond plus a bond to another styrene monomer.
There is evidence to indicate the Big Bang may have resulted from another, earlier universe collapsing in on itself, rather than from expanding from a point on infinitely hot and dense material. Instead, the universe appears to be going through constant phases of expansion (as it is at present) and contraction in a never-ending cycle. This theory of universe formation, known as the Big Bounce, was first proposed almost a century ago.
Once scientists understood that the universe was expanding, they immediately realized that it would have been smaller in the past. At some point in the past, the entire universe would have been a single point. This point, later called the big bang, was the beginning of the universe as we understand it today.