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arXiv · 2107.04756

Quintessential constant-roll inflation

Mehdi Shokri·Jafar Sadeghi·Saeed Noori Gashti
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Abstract

We investigate a single field model in the context of the constant-roll inflation in which inflaton moves down to the minimum point of the potential with a constant rate of rolling. We use a quintessential inflationary model obtained by a Lorentzian function which is dependent on the number of e-folds. We present the inflationary analysis for the model and find the observational constraints on the parameters space using the observations of CMB anisotropies \textit{i.e.} the Planck and Keck/array datasets. We find the observationally acceptable values of the Width of the Lorentzian function as $0.3<Γ\leq0.5$ at the $68\%$ CL and $Γ\leq0.3$ at the $95\%$ CL when $ξ=120$, $|β|=0.02$ and $N=60$. Also, we acquire the observationally favoured values of the amplitude of the Lorentzian function as $400<ξ\leq600$ at the $68\%$ CL and $ξ\leq400$ at the $95\%$ CL when $Γ=0.1$, $|β|=0.02$ and $N=60$. Moreover, we study the model from the Weak Gravity Conjecture approach using the swampland criteria.

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Mehdi Shokri, Jafar Sadeghi, Saeed Noori Gashti. 2021-11-21. Quintessential constant-roll inflation. https://arxiv.org/abs/2107.04756

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