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arXiv · 2010.00113

A new branch of inflationary speed limits

Dayshon Mathis·Alexandros Mousatov·George Panagopoulos·Eva Silverstein
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Abstract

We present a new mechanism for inflation which exhibits a speed limit on scalar motion, generating accelerated expansion even on a steep potential. This arises from explicitly integrating out the short modes of additional fields coupled to the inflaton $\phi$ via a dimension six operator, yielding an expression for the effective action which includes a nontrivial (logarithmic) function of $(\partial\phi)^2$. The speed limit appears at the branch cut of this logarithm arising in a large flavor expansion, similarly to the square root branch cut in DBI inflation arising in a large color expansion. Finally, we describe observational constraints on the parameters of this model.

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Dayshon Mathis, Alexandros Mousatov, George Panagopoulos, Eva Silverstein. 2020-09-30. A new branch of inflationary speed limits. https://doi.org/10.1007/jhep10(2021)199

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