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arXiv · 1408.5904

Power Spectrum of Inflationary Attractors

Benedict J. Broy·Diederik Roest·Alexander Westphal
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Abstract

Inflationary attractors predict the spectral index and tensor-to-scalar ratio to take specific values that are consistent with Planck. An example is the universal attractor for models with a generalised non-minimal coupling, leading to Starobinsky inflation. In this paper we demonstrate that it also predicts a specific relation between the amplitude of the power spectrum and the number of e-folds. The length and height of the inflationary plateau are related via the non-minimal coupling: in a wide variety of examples, the observed power normalisation leads to at least 55 flat e-foldings. Prior to this phase, the inflationary predictions vary and can account for the observational indications of power loss at large angular scales.

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Benedict J. Broy, Diederik Roest, Alexander Westphal. 2015-01-20. Power Spectrum of Inflationary Attractors. https://doi.org/10.1103/physrevd.91.023514

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