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arXiv · 1503.07909

Cosmological Attractors from $\alpha$-Scale Supergravity

Diederik Roest·Marco Scalisi
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Abstract

The Planck value of the spectral index can be interpreted as $n_s = 1 - 2/N$ in terms of the number of e-foldings $N$. An appealing explanation for this phenomenological observation is provided by $\alpha$-attractors: the inflationary predictions of these supergravity models are fully determined by the curvature of the Kahler manifold. We provide a novel formulation of $\alpha$-attractors which only involves a single chiral superfield. Our construction involves a natural deformation of no-scale models, and employs these to construct a De Sitter plateau with an exponential fall-off. Finally, we show how analogous structures with a flat Kahler geometry arise as a singular limit of such $\alpha$-scale models.

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Diederik Roest, Marco Scalisi. 2015-03-26. Cosmological Attractors from $\alpha$-Scale Supergravity. https://doi.org/10.1103/physrevd.92.043525

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