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arXiv · 1711.07450

Anisotropic Inflation with Derivative Couplings

Jonathan Holland·Sugumi Kanno·Ivonne Zavala
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Abstract

We study anisotropic inflationary solutions when the inflaton and its derivative couple to a vector field. This type of coupling is motivated by D-brane inflationary models, in which the inflaton, and a vector field living on the D-brane, couple disformally (derivatively). We start by studying a phenomenological model where we show the existence of anisotropic solutions and demonstrate their stability via a dynamical system analysis. Compared to the case without a derivative coupling, the anisotropy is reduced and thus can be made consistent with current limits, while the value of the slow-roll parameter remains almost unchanged. We also discuss solutions for more general cases, including D-brane like couplings.

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Jonathan Holland, Sugumi Kanno, Ivonne Zavala. 2017-11-20. Anisotropic Inflation with Derivative Couplings. https://doi.org/10.1103/physrevd.97.103534

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