English

Second-order corrections to Starobinsky inflation

Cosmology and Nongalactic Astrophysics 2023-11-14 v4 General Relativity and Quantum Cosmology

Abstract

Higher-order theories of gravity are extensions to general relativity (GR) motivated mainly by high-energy physics searching for GR ultraviolet completeness. They are characterized by the inclusion of correction terms in the Einstein-Hilbert action that leads to higher-order field equations. In this paper, we propose investigating inflation due to the GR extension built with all correction terms up to the second-order involving only the scalar curvature RR, namely, R2R^{2}, R3R^{3}, RRR\square R. We investigate inflation within the Friedmann cosmological background, where we study the phase space of the model, as well as explore inflation in slow-roll leading-order. Furthermore, we describe the evolution of scalar perturbations and properly establish the curvature perturbation. Finally, we confront the proposed model with recent observations from Planck, BICEP3/Keck, and BAO data.

Keywords

Cite

@article{arxiv.2207.02103,
  title  = {Second-order corrections to Starobinsky inflation},
  author = {G. Rodrigues-da-Silva and L. G. Medeiros},
  journal= {arXiv preprint arXiv:2207.02103},
  year   = {2023}
}

Comments

15 pages plus appendices and references (two-column), 4 figures; v4: In this version that matches to the one accepted by the EPJC, section IV. C. was expanded, new appendix B was added, we made improvements throughout the manuscript and references were added

R2 v1 2026-06-24T12:14:38.311Z