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.
Actual proof of the Milky Way consisting of many stars came in 1610 when Galileo Galilei used a telescope to study the Milky Way and discovered that it is composed of a huge number of faint stars.