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arXiv · 2008.02494

Note on initial conditions for small-field inflation

Ignatios Antoniadis·Auttakit Chatrabhuti·Hiroshi Isono·Spyros Sypsas
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Abstract

We show that initial conditions for small-field inflation can be determined quantum mechanically by introducing a suitable flattened region in the scalar potential. The inflaton is then driven towards the slow-roll attractor solution exponentially fast, desensitising inflation from the initial velocity and partially evading the so-called overshoot problem. We give an explicit example in the context of hilltop inflation by introducing an ultra slow-roll plateau around the maximum of the potential and analyse its effect on the phase-space trajectories.

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Ignatios Antoniadis, Auttakit Chatrabhuti, Hiroshi Isono, Spyros Sypsas. 2020-08-06. Note on initial conditions for small-field inflation. https://doi.org/10.1103/physrevd.102.103510

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