Thermally-induced vacuum instability in a single plane wave

TL;DR

This paper challenges the traditional view of vacuum stability in electromagnetic plane waves by demonstrating that thermal effects can induce vacuum decay into electron-positron pairs, with a rate depending on field strength and temperature.

Contribution

It introduces a analysis showing that thermal effects cause vacuum instability in a single plane wave, even at zero frequency, which was previously considered stable.

Findings

Thermal vacuum decays into pairs in a plane wave.

Pair-production rate depends nonperturbatively on field amplitude and temperature.

Vacuum instability occurs even in the zero-frequency limit.

Abstract

Ever since Schwinger published his influential paper [J. Schwinger, Phys. Rev. \textbf{82}, 664 (1951)], it has been unanimously accepted that the vacuum is stable in the presence of an electromagnetic plane wave. However, we advance an analysis that indicates this statement is not rigorously valid in a real situation, where thermal effects are present. We show that the thermal vacuum, in the presence of a single plane-wave field, even in the limit of zero frequency (a constant crossed field), decays into electron-positron pairs. Interestingly, the pair-production rate is found to depend nonperturbatively on both the amplitude of the constant crossed field and on the temperature.