Brownian ratchet (nonfiction): Difference between revisions
(Created page with "In the philosophy of thermal and statistical physics, the '''Brownian ratchet''' or '''Feynman-Smoluchowski ratchet''' is a thought experiment about a...") |
(No difference)
|
Revision as of 09:16, 11 September 2016
In the philosophy of thermal and statistical physics, the Brownian ratchet or Feynman-Smoluchowski ratchet is a thought experiment about an apparent perpetual motion machine.
It was first analysed in 1912 by Polish physicist Marian Smoluchowski, and later popularized by American Nobel laureate physicist Richard Feynman in a physics lecture at the California Institute of Technology on May 11, 1962, during his Messenger Lectures series The Character of Physical Law in Cornell University.
The simple machine, consisting of a tiny paddle wheel and a ratchet, appears to be an example of a Maxwell's demon, able to extract useful work from random fluctuations (heat) in a system at thermal equilibrium in violation of the second law of thermodynamics.
Detailed analysis by Feynman and others showed why it cannot actually do this.
In the News
Fiction cross-reference
Nonfiction cross-reference
- [[Maxwell's demon (nonfiction)
- Physics (nonfiction)
External links:
- Brownian ratchet @ Wikipedia
Attribution: