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Fluctuations of Fluctuation-Induced "Casimir" Forces

Denis Bartolo·Armand Ajdari·Jean-Baptiste Fournier·Ramin Golestanian
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Abstract

The force experienced by objects embedded in a correlated medium undergoing thermal fluctuations--the so-called fluctuation--induced force--is actually itself a fluctuating quantity. We compute the corresponding probability distribution and show that it is a Gaussian centered on the well-known Casimir force, with a non-universal standard deviation that can be typically as large as the mean force itself. The relevance of these results to the experimental measurement of fluctuation-induced forces is discussed, as well as the influence of the finite temporal resolution of the measuring apparatus.

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Denis Bartolo, Armand Ajdari, Jean-Baptiste Fournier, Ramin Golestanian. 2002-08-06. Fluctuations of Fluctuation-Induced "Casimir" Forces. https://doi.org/10.1103/physrevlett.89.230601

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