Constant-Roll Inflation

Hayato Motohashi

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arXiv · 2504.16757

Constant-Roll Inflation

Hayato Motohashi

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Abstract

Constant-roll inflation is a distinctive class of phenomenological inflationary models in which the inflaton's rate of roll remains constant. It provides an exact solution that is compatible with the latest observational constraints and offers a natural framework for enhancing the curvature power spectrum, which is relevant to the formation of primordial black holes. In this paper, I review constant-roll inflation in memory of Alexei Starobinsky.

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Hayato Motohashi. 2025-04-23. Constant-Roll Inflation. https://arxiv.org/abs/2504.16757

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