Spotting deviations from R^2 inflation
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.
Keywords
Cite
@article{arxiv.1603.05537,
title = {Spotting deviations from R^2 inflation},
author = {Alvaro de la Cruz-Dombriz and Emilio Elizalde and Sergei D. Odintsov and Diego Saez-Gomez},
journal= {arXiv preprint arXiv:1603.05537},
year = {2016}
}
Comments
24 pages, 1 figure, minor changes, version matching published version, conclusions unchanged. arXiv admin note: text overlap with arXiv:1411.1636 by other authors