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arXiv · 2004.05238

Natural inflation with natural number of e-foldings

Matthew Civiletti·Brandon Delacruz
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Abstract

We examine natural inflation without the use of the standard slow-roll approximation by considering the number of physical e-folds $\ln (a_eH_e/aH)$. We show that $\tilde{H} = aH \propto \cos(A \phi/2)^{2/A^2} \sin(A \phi/2)$ produces a natural inflationary scenario. This model may be solved exactly, showing that the slow-roll approximation overestimates the tensor-to-scalar ratio by about $13-19 \%$ for $n_s \approx 0.96$ and $50-60$ $e$-folds.

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Matthew Civiletti, Brandon Delacruz. 2020-04-10. Natural inflation with natural number of e-foldings. https://doi.org/10.1103/physrevd.101.043534

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