QED effective action at finite temperature
Abstract
The QED effective Lagrangian in the presence of an arbitrary constant electromagnetic background field at finite temperature is derived in the imaginary-time formalism to one-loop order. The boundary conditions in imaginary time reduce the set of gauge transformations of the background field, which allows for a further gauge invariant and puts restrictions on the choice of gauge. The additional invariant enters the effective action by a topological mechanism and can be identified with a chemical potential; it is furthermore related to Debye screening. In concordance with the real-time formalism, we do not find a thermal correction to Schwinger's pair-production formula. The calculation is performed on a maximally Lorentz covariant and gauge invariant stage.
Keywords
Cite
@article{arxiv.hep-ph/9812436,
title = {QED effective action at finite temperature},
author = {Holger Gies},
journal= {arXiv preprint arXiv:hep-ph/9812436},
year = {2009}
}
Comments
9 pages, REVTeX, 1 figure, typos corrected, references added, final version to appear in Phys. Rev. D