# Electromagnetic coupling effects in natural inflation

## TL;DR

This paper investigates how electromagnetic coupling influences natural inflation by deriving a stochastic Langevin equation for the inflaton and analyzing its correlation functions, shedding light on the effects on power spectrum and non-Gaussianity.

## Contribution

It systematically evaluates electromagnetic effects in natural inflation using the Schwinger-Keldysh formalism and derives the inflaton's stochastic dynamics and correlation functions.

## Key findings

- Derived Langevin equation for inflaton with electromagnetic effects
- Calculated two-point and three-point correlation functions
- Provided insights into power spectrum and non-Gaussianity modifications

## Abstract

In this work we study the effects of the electromagnetic coupling in natural inflation in a systematic manner using the Schwinger-Keldysh formalism. The corresponding influence functional is evaluated to one-loop level. It can be interpreted as due to a single stochastic force. The equation of motion of the inflaton field is therefore given in the form of a Langevin equation. Lastly, the two-point and the three-point correlation functions of the inflaton field are worked out. They are related to the power spectrum and the nongaussianity of the inflaton field, respectively.