Axion monodromy inflation with sinusoidal corrections

TL;DR

This paper explores axion monodromy inflation with sinusoidal corrections, showing it can produce larger tensor-to-scalar ratios and significant spectral index running, with implications for single and double inflation scenarios.

Contribution

It introduces a combined potential model with sinusoidal corrections affecting inflationary fluctuations and demonstrates its ability to generate observable tensor-to-scalar ratios and spectral index running.

Findings

Larger tensor-to-scalar ratio (~0.1-0.15) in single inflation scenario.

Double inflation scenario achieves large tensor-to-scalar ratio and negative spectral index running.

Sinusoidal corrections significantly influence inflationary fluctuation predictions.

Abstract

We study the axion monodromy inflation with a non-perturbatively generated sinusoidal term. The potential form is a mixture between the natural inflation and the axion monodromy inflation potentials. The sinusoidal term is subdominant in the potential, but leaves significant effects on the resultant fluctuation generated during inflation. A larger tensor-to-scalar ratio can be obtained in our model. We study two scenarios, single inflation scenario and the double inflation scenario. In the first scenario, the axion monodromy inflation with a sufficient number of e-fold generates a larger tensor-to-scalar ratio about $0.1 - 0.15$ but also a tiny running of spectral index. In the second scenario of double inflation, axion monodromy inflation is its first stage and, we assume another inflation follows. In this case, our model can realize a larger tensor-to-scalar ratio and a large negative running of spectral index simultaneously.