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arXiv · 2209.02434

Non-minimally coupled Natural Inflation: Palatini and Metric formalism with the recent BICEP/Keck

Nilay Bostan
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Abstract

In this work, we show the effect of the non-minimal coupling $\xi \phi^2 R$ on the inflationary parameters by considering the single-field inflation and present the inflationary predictions of the appealing potential for the particle physics viewpoint: Natural Inflation, an axion-like inflaton which has a cosine-type periodic potential and the inflaton naturally emerges as a pseudo-Nambu-Goldstone boson with a spontaneously broken global symmetry. We present the inflationary predictions for this potential, $n_s$, $r$, and $\alpha=\mathrm{d}n_s/\mathrm{d}\ln k$. In addition, we assume standard thermal history after inflation, and using this, for considered potential, we show compatible regions for the $n_s$, $r$ within the recent BICEP/Keck results.

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Nilay Bostan. 2022-09-06. Non-minimally coupled Natural Inflation: Palatini and Metric formalism with the recent BICEP/Keck. https://doi.org/10.1088/1475-7516%2F2023%2F02%2F063

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