Brownian ratchet

English

Etymology

In reference to Brownian motion.

Noun

Brownian ratchet (plural Brownian ratchets)

1. (physics) An apparent perpetual motion machine, the subject of a thought experiment, that would consist of a tiny paddle wheel and a ratchet, and might seem to be able to extract useful work from random fluctuations (heat) in a system at thermal equilibrium, in violation of the second law of thermodynamics.

   Synonym: Feynman-Smoluchowski ratchet

See also

• Maxwell's demon