One-loop electromagnetic correlators of SQED in power-law inflation

TL;DR

This paper analyzes one-loop electromagnetic correlators in scalar QED during power-law inflation, revealing significant quantum effects due to gravitational particle production and emphasizing the need for non-perturbative approaches.

Contribution

It provides the first detailed computation of one-loop electric and magnetic correlators in power-law inflation, highlighting the importance of non-perturbative effects.

Findings

One-loop corrections show secular growth and infrared sensitivity.

Electric and magnetic correlators exhibit a hierarchy influenced by inflation dynamics.

Gravitational particle production enhances quantum effects in the correlators.

Abstract

We examine scalar quantum electrodynamics in power-law inflation space-time, and compute the one-loop correction to electric and magnetic field correlators at superhorizon separations. The effect at one-loop descends from the coupling of the vector to the charged scalar current which is greatly enhanced due to gravitational particle production. We conclude that non-perturbative effects must exist due to (i) secular growth, (ii) spatial running, and (iii) infrared sensitivity of the one-loop correction to the correlators. Electric and magnetic correlators exhibit a hierarchy that is due to Faraday's law and accelerated expansion, and must hold non-perturbatively.