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arXiv · 1609.04336

On the Difference Between the Vacuum Casimir Energies for Grounded and Isolated Conductors

C. D. Fosco·F. C. Lombardo·F. D. Mazzitelli
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Abstract

We study the vacuum (i.e., zero-temperature) Casimir energy for a system of neutral conductors which are isolated, as opposed to grounded. The former is meant to describe a situation where the total charge on each conductor, as well as all of its fluctuations, vanishes, while the latter describes a situation where the conductors are connected to a charge reservoir. We compute the difference between the vacuum energies for a given system of conductors, but subjected to the two different conditions stated above. The results can be written in terms of a generalized, frequency-dependent capacitance matrix of the system. Using a multipolar expansion, we show that the grounded Casimir energy includes a monopole-monopole interaction term that is absent in the isolated case in the large distance limit

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C. D. Fosco, F. C. Lombardo, F. D. Mazzitelli. 2016-09-14. On the Difference Between the Vacuum Casimir Energies for Grounded and Isolated Conductors. https://doi.org/10.1103/physrevd.94.085024

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