Gray goo

Hypothetical end-of-the-world scenario

Gray goo is a hypothetical global catastrophic scenario involving molecular nanotechnology in which out-of-control self-replicating machines consume all biomass on Earth while building many more of themselves, a scenario that has been called ecophagy (the literal consumption of the ecosystem). The original idea assumed machines were designed to have this capability, while popularizations have assumed that machines might somehow gain this capability by accident.

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