2015/09/29 by Panagiota Kanti, Kanti, Panagiota
Physics and Astronomy · #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences #General Relativity and Quantum Cosmology (gr-qc) #High Energy Physics - Phenomenology (hep-ph) #High Energy Physics - Theory (hep-th) #astro-ph.CO #gr-qc #hep-ph #hep-th
paper · pdf · doi:10.48550/arxiv.1509.08610
6 pages, 3 figures, to appear in the proceedings of the Fourteenth Marcel Grossmann Meeting - MG14 (Early Universe session - EU3), Rome, July 12-18, 2015
arxiv created 2015/09/29 · arxiv updated 2015/09/30
We consider a gravitational theory that contains the Einstein term, a scalar field and the quadratic Gauss-Bonnet term. We focus on the early-universe dynamics, and demonstrate that the Ricci scalar does not affect the cosmological solutions at early times, when the curvature is strong. We then consider a pure scalar-GB theory with a quadratic coupling function: for a negative coupling parameter, we obtain solutions that contain always an inflationary, de Sitter phase, while for a positive coupling function, we find instead expanding singularity-free solutions.