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arXiv · 1904.06289

Dynamical Analysis of Attractor Behavior in Constant Roll Inflation

Abstract

There has been considerable recent interest in a new class of non-slow roll inflationary solutions known as \textit{constant roll} inflation. Constant roll solutions are a generalization of the ultra-slow roll (USR) solution, where the first Hubble slow roll parameter $ε$ is small, but the second Hubble slow roll parameter $η$ is not. While it is known that the USR solutions represent dynamical transients, there has been some disagreement in literature about whether or not large-$η$ constant roll solutions are attractors or are also a class of transient solutions. In this paper we show that the large-$η$ constant roll solutions do in fact represent transient solutions by performing stability analysis on the exact analytic (large-$η$) constant roll solutions.

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BibTeXRIS

Wei-Chen Lin, Michael J. P. Morse, William H. Kinney. 2019-09-11. Dynamical Analysis of Attractor Behavior in Constant Roll Inflation. https://doi.org/10.1088/1475-7516%2F2019%2F09%2F063

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