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arXiv · hep-th/0102193

The heat kernel coefficients for the dielectric cylinder

M. Bordag·I. G. Pirozhenko
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Abstract

We calculate the \hkks for the \elm field in the background of a dielectric cylinder with non equal speeds of light inside and outside. The coefficient $a_{2}$ whose vanishing makes the vacuum energy of a massless field unique, turns out to be zero in dilute order, i.e., in order $(\ep-1)^{2}$, and nonzero beyond. As a consequence, the vanishing of the vacuum energy in the presence of a dielectric cylinder found by Casimir-Polder summation must take place irrespectively of the methods by which it might be calculated.

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M. Bordag, I. G. Pirozhenko. 2001-02-27. The heat kernel coefficients for the dielectric cylinder. https://doi.org/10.1103/physrevd.64.025019

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