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Forces Induced by Non-Equilibrium Fluctuations: The Soret-Casimir Effect

Ali Najafi·Ramin Golestanian
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Abstract

The notion of fluctuation-induced forces is generalized to the cases where the fluctuations have nonequilibrium origin. It is shown that a net force is exerted on a single flat plate that restricts scale-free fluctuations of a scalar field in a temperature gradient. This force tends to push the object to the colder regions, which is a manifestation of thermophoresis or the Soret effect. In the classic two-plate geometry, it is shown that the Casimir forces exerted on the two plates differ from each other, and thus the Newton's third law is violated.

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Ali Najafi, Ramin Golestanian. 2003-08-19. Forces Induced by Non-Equilibrium Fluctuations: The Soret-Casimir Effect. https://doi.org/10.1209/epl%2Fi2004-10275-5

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