The stress-energy tensor between metallic plates: A lorentz force approach

Abstract

It is argued that the non-zero components of the electromagnetic stress-energy tensor between metallic plates, at zero temperature, are positive quantities, as opposed to previous calculations. Furthermore, they are of infinite magnitude for ideal conductors. In the case of imperfect conductivity, the computed components generally depend on the model we use to describe the metal and are cutoff dependent; an example is worked out for the case of an exponential decay. In this case, the zero temperature tensor splits into a cutoff dependent part and a separation dependent part. Although the separation dependent terms are exactly those found first by Brown and Maclay, we argue that the cutoff dependent terms, arising from physical forces felt by the conductors, cannot be droped out by a renormalization. The temperature correction tensor that we compute coincides with the one found by Brown and Maclay.