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arXiv · 1907.06204

Electromagnetic coupling effects in natural inflation

Hing-Tong Cho·Kin-Wang Ng
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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.

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Hing-Tong Cho, Kin-Wang Ng. 2019-07-14. Electromagnetic coupling effects in natural inflation. https://doi.org/10.1088/1361-6382%2Fab8600

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