Cryonics is the practice of preserving people who are dying in liquid nitrogen soon after their heart stops. The idea is that most of your brain's information content is still intact right after you've "died", i.e. medical death or legal death. If humans invent molecular nanotechnology or brain emulation techniques, it may be possible to reconstruct the consciousness of cryopreserved patients.

Related: Life Extension, a more general tag about ways to avoid death.

Cryonics-associated issues commonly raised on LessWrong

Pro-cryonics points...

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