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arXiv · 2211.07775

On Warm Natural Inflation and Planck 2018 constraints

Mahmoud AlHallak·Khalil Kalid Al Said·Nidal Chamoun·Moustafa Sayem El-Daher
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Abstract

We investigate Natural Inflation with non-minimal coupling to gravity, characterized either by a quadratic or a periodic term, within the Warm Inflation paradigm during the slow roll stage, in both strong and weak dissipation limits, and show that, in the case of $T$-linearly dependent dissipative term, it can accommodate the spectral index $n_s$ and tensor-to-scalar ratio $r$ observables given by Planck 2018 constraints, albeit with a too small value of the e-folding number to solve the horizon problem, providing thus only a partial solution to Natural Inflation issues. Assuming a $T$-cubically dependent dissipative term can provide a solution to this e-folding number issue.

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Mahmoud AlHallak, Khalil Kalid Al Said, Nidal Chamoun, Moustafa Sayem El-Daher. 2022-11-14. On Warm Natural Inflation and Planck 2018 constraints. https://arxiv.org/abs/2211.07775

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