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arXiv · 1603.05537

Spotting deviations from R^2 inflation

Alvaro de la Cruz-Dombriz·Emilio Elizalde·Sergei D. Odintsov·Diego Saez-Gomez
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Abstract

We discuss the soundness of inflationary scenarios in theories beyond the Starobinsky model, namely a class of theories described by arbitrary functions of the Ricci scalar and the K-essence field. We discuss the pathologies associated with higher-order equations of motion which will be shown to constrain the stability of this class of theories. We provide a general framework to calculate the slow-roll parameters and the corresponding mappings to the theory parameters. For paradigmatic gravitational models within the class of theories under consideration we illustrate the power of the Planck/Bicep2 latest results to constrain such gravitational Lagrangians. Finally, bounds for potential deviations from Starobinsky-like inflation are derived.

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Alvaro de la Cruz-Dombriz, Emilio Elizalde, Sergei D. Odintsov, Diego Saez-Gomez. 2016-05-25. Spotting deviations from R^2 inflation. https://doi.org/10.1088/1475-7516%2F2016%2F05%2F060

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