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arXiv · 1509.08610

Early-time cosmological solutions in scalar-Gauss-Bonnet theory

Panagiota Kanti
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Abstract

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.

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Panagiota Kanti. 2015-09-29. Early-time cosmological solutions in scalar-Gauss-Bonnet theory. https://arxiv.org/abs/1509.08610

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