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arXiv · 1805.11241

On the entropy of a spherical plasma shell

M. Bordag·K. Kirsten
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Abstract

Negative entropy was repeatedly observed in the Casimir effect caused by dissipation or geometry. However, it was restricted to subsystems. Recently the question about the entropy for a complete Casimir effect like configuration was raised. In the present paper we consider a spherical plasma shell which can be considered as a (crude) model for a giant carbon molecule (e.g., $C_{60}$). The entropy is free of ultraviolet divergences and its calculation does not need any regularization. We calculate the entropy numerically and demonstrate unambiguously the existence of a region where it takes negative values. This region is at small values of temperature and plasma frequency (in units of the radius).

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M. Bordag, K. Kirsten. 2018-05-29. On the entropy of a spherical plasma shell. https://doi.org/10.1088/1751-8121/aae4c1

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