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arXiv · 1303.6628

Gradient expansion of superhorizon perturbations in G-inflation

Noemi Frusciante·Shuang-Yong Zhou·Thomas P. Sotiriou
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Abstract

We develop the gradient expansion formalism for shift-symmetric Galileon-type actions. We focus on backgrounds that undergo inflation, work in the synchronous gauge, and obtain a general solution up to second order without imposing extra conditions at first order. The solution simplifies during the late stages of inflation. We also define a curvature perturbation conserved up to first order.

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Noemi Frusciante, Shuang-Yong Zhou, Thomas P. Sotiriou. 2013-07-04. Gradient expansion of superhorizon perturbations in G-inflation. https://doi.org/10.1088/1475-7516%2F2013%2F07%2F020

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