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arXiv · 1808.01325

Observational Constraints on Constant Roll Inflation

Jose T. Galvez Ghersi·Alex Zucca·Andrei V. Frolov
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Abstract

Constant-roll inflation was recently introduced by Motohashi, Starobinsky and Yokoyama as a phenomenological way to parametrize deviations from the slow-roll scenarios. In this paper, we investigate the dynamics of both the background and the perturbations in this model, without making any slow-roll assumptions. The perturbation spectra are computed with an efficient and accurate novel method that allowed us to quickly scan the parameter space of constant-roll inflation. We derive the constraints on the model parameters from the cosmic microwave background anisotropy measurements provided by the joint analysis of the Planck Collaboration and the BICEP2/Keck Array data.

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Jose T. Galvez Ghersi, Alex Zucca, Andrei V. Frolov. 2019-05-08. Observational Constraints on Constant Roll Inflation. https://doi.org/10.1088/1475-7516%2F2019%2F05%2F030

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