Cryogenics is an entire field of physical science. It is the study of matter at temperatures much colder than those that occur naturally on Earth. Cryogenic temperatures are considerably lower than those encountered in ordinary physical processes. There is another field of interest associated with very cold temperature-cryonics. Cryonics is the practice of freezing of people, or just their heads, in liquid nitrogen after death in hopes that one day they can be thawed to the out cured of what killed them. "This could be the most profound revolution in human history. It is the change to live as long as you want." (Goodavage, 1990) Cryonics is not a scienc