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arXiv · 1010.0537

Casmir-Lifshitz Forces and Entropy

Lev P. Pitaevskii
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Abstract

It is shown that the violation of the positiveness of the entropy due to the Casimir-Lifshitz interaction claimed in several papers is an artifact related to an improper interpretation of the "Casimir entropy", which actually is a difference of two positive terms. It is explained that at definite condition this "Casimir entropy" must be negative. A direct derivation of the low temperature behavior of the surface entropy of a metallic surface in conditions of the anomalous skin effect is given and singular temperature dependency of this quantity is discussed. In conclusion a hydrodynamic example of the entropy of a liquid film is considered. It occurs that the entropy of a film of finite thickness and a liquid half-space behave differently at T tends to 0.

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Lev P. Pitaevskii. 2010-10-04. Casmir-Lifshitz Forces and Entropy. https://doi.org/10.1142/s0217751x1004958x

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