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arXiv · hep-th/9407036

Nonlinear interaction between electromagnetic fields at high temperature

Fernando T. Brandt·Josif Frenkel·John C. Taylor
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Abstract

The electron-positron `box' diagram produces an effective action which is fourth order in the electromagnetic field. We examine the behaviour of this effective action at high-temperature (in analytically continued imaginary-time thermal perturbation theory). We argue that there is a finite, nonzero limit as $T\rightarrow \infty$ (where $T$ is the temperature). We calculate this limit in the nonrelativistic static case, and in the long-wavelength limit. We also briefly discuss the self-energy in 2-dimensional QED, which is similar in some respects.

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Fernando T. Brandt, Josif Frenkel, John C. Taylor. 1994-07-06. Nonlinear interaction between electromagnetic fields at high temperature. https://doi.org/10.1103/physrevd.50.4110

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