Cryonics

From RationalWiki

Cryonics is the industry of freezing dead bodies in liquid nitrogen in hopes of a future resurrection at the hands of advanced medical technology. Created in the 1960s, cryonics in various forms has become something of a trope of science fiction, either as a serious plot device (the Alien tetralogy), a source of humor (Futurama, Sleeper), or sheer boneheaded incomprehensibility (Vanilla Sky). For funerary and legal purposes, cryonics is largely considered an extremely elaborate form of burial, and cannot be legally performed on someone who has not been declared medically dead.

The essential idea is to quick-freeze the body (or, for less money, the head alone) in a bath of liquid nitrogen, and preserve it for as long as possible (preferably centuries), trying to minimize damage from ice crystals and preserve the body in as close to its original state as possible in order to simplify the task of bringing the subject back to life with as-yet-unknown medical technology (conventional wisdom in the cryonics field seems to favor nanotechnology as the most likely route at this time). The body is given large doses of anti-clotting drugs, as well as being infused with cryoprotectant chemicals meant to cause the water within the body to freeze in a glassy form rather than crystallizing and puncturing cells.

While cryonics has proven fairly effective for single cells (it is widely used in in vitro fertilization to store fertilized zygotes for later implantation), scientific opinion outside the movement has been rather negative, citing the difficulties in quickly reaching and maintaining a sufficiently low temperature to preserve the body without cell damage (even a slight thaw would destroy the body for its intended purpose), as well as the unlikelihood of preserving brain patterns. Some simpler experiments have been done involving suspended animation, in which the life processes of the subject ^[1] are reduced to almost nothing for a short period then brought back, but the feasibility of bringing back a human being frozen under current technology remains iffy at best, if not likely impossible.