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arXiv · hep-th/9912176

Casimir energy of a dilute dielectric ball in the mode summation method

G. Lambiase·G. Scarpetta·V. V. Nesterenko
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Abstract

In the $(ε_1-ε_2)^2$--approximation the Casimir energy of a dilute dielectric ball is derived using a simple and clear method of the mode summation. The addition theorem for the Bessel functions enables one to present in a closed form the sum over the angular momentum before the integration over the imaginary frequencies. The linear in $(ε_1-ε_2)$ contribution into the vacuum energy is removed by an appropriate subtraction. The role of the contact terms used in other approaches to this problem is elucidated.

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G. Lambiase, G. Scarpetta, V. V. Nesterenko. 2001-01-08. Casimir energy of a dilute dielectric ball in the mode summation method. https://doi.org/10.1142/s0217732301005291

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