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arXiv · 1209.6072

The Casimir effect as a sum-over-modes in dissipative systems

Francesco Intravaia·Ryan Behunin
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Abstract

The aim of this paper is to show that within the open-system framework the sum-over-modes approach \'a la Casimir leads to the Lifshitz formula for the Casimir free energy. A general result applicable to arbitrary geometries is obtained through the use of Ford, Lewis, & O'Connell's remarkable formula. Additionally, we address the possibility for obtaining the Casimir energy as a sum over complex "modes". We show in this case that the standard sum-over-modes formula must be suitably generalized to avert unphysical complex energies. Finally, we apply our results to several standard examples.

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Francesco Intravaia, Ryan Behunin. 2012-09-26. The Casimir effect as a sum-over-modes in dissipative systems. https://doi.org/10.1103/physreva.86.062517

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