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Casimir energy and realistic model of dilute dielectric ball

Valery N. Marachevsky
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Abstract

The Casimir energy of a dilute homogeneous nonmagnetic dielectric ball at zero temperature is derived analytically for the first time for an arbitrary physically possible frequency dispersion of dielectric permittivity $ε(iω)$. A microscopic model of dielectrics is considered, divergences are absent in calculations because an average interatomic distance $λ$ is a {\it physical} cut-off in the theory. This fact has been overlooked before, which led to divergences in various macroscopic approaches to the Casimir energy of connected dielectrics.

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Valery N. Marachevsky. 2001-06-01. Casimir energy and realistic model of dilute dielectric ball. https://doi.org/10.1142/s0217732301004078

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