Pair production in a plane wave by thermal background photons.

Ever since Schwinger published his influential paper [ J. Schwinger Phys. Rev. 82 664 (1951)], the maxim that there can be no pair creation in a plane wave has been often cited. We advance an analysis that indicates that in any real situation, where thermal effects are present, in a single plane-wave field, even in the limit of zero frequency (a constant crossed field), thermal photons can seed pair creation. Interestingly, the pair-production rate is found to depend nonperturbatively on both the amplitude of the constant crossed field and on the temperature. [ABSTRACT FROM AUTHOR]