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arXiv · 1502.01246

On the initial conditions for inflation with plateau potentials: the $R+R^2$ (super)gravity case

Ioannis Dalianis·Fotis Farakos
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Abstract

We discuss the initial conditions problem for inflation driven by the vacuum energy of a plateau potential, and in particular the Starobinsky inflation. We show that the supergravity embedding of the $R+R^2$ theory naturally decreases the size of the acausal homogeneity, required for the low-scale inflation to occur, thanks to the presence of the dynamical pure supergravitational "auxiliary" fields. We examine the evolution of the $R+R^2$ fields within a FLRW Universe. We also find a dependence of the initial conditions problem on the background spatial curvature.

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Ioannis Dalianis, Fotis Farakos. 2015-12-01. On the initial conditions for inflation with plateau potentials: the $R+R^2$ (super)gravity case. https://doi.org/10.1088/1475-7516%2F2015%2F07%2F044

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