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Comment on the sign of the Casimir force

C. P. Bachas
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Abstract

I show that reflection positivity implies that the force between any mirror pair of charge-conjugate probes of the quantum vacuum is attractive. This generalizes a recent theorem of Kenneth and Klich to interacting quantum fields, to arbitrary semiclassical bodies, and to quantized probes with non-overlapping wavefunctions. I also prove that the torques on charge-conjugate probes tend always to rotate them into a mirror-symmetric position.

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C. P. Bachas. 2007-04-03. Comment on the sign of the Casimir force. https://doi.org/10.1088/1751-8113/40/30/028

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