August 6, 2002
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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In the present work we propose a method to determine fluctuation induced forces in non equilibrium systems. These forces are the analogue of the well known Casimir forces, which were originally introduced in Quantum Field theory and later extended to the area of Critical Phenomena. The procedure starts from the observation that many non equilibrium systems exhibit long-range correlations and the associated structure factors diverge in the long wavelength limit. The introducti...
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It has been argued since 1948, when it was experimentally demonstrated, that the Casimir effect-where two non-charged conducting plates have a weak but measurable force on each other dependent on the inverse fourth power of the distance between them-shows the reality of vacuum zero-point fluctuations. This "proof" of the reality of vacuum fluctuations has been repeated in many quantum field theory books and papers subsequent to 1948. The attractive force is generally ascribed...
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