Galileon bounce after ekpyrotic contraction

TL;DR

This paper presents a cosmological model combining ekpyrotic contraction with a Galileon-induced bounce, providing analytical and numerical insights into the bounce mechanism within weak gravity and non-perturbative regimes.

Contribution

It introduces a simple model integrating ekpyrotic contraction with a Galileon bounce, analyzing the bounce analytically and numerically beyond perturbative limits.

Findings

Bounce occurs within the weak gravity regime

Numerical analysis extends understanding to non-perturbative regimes

Model demonstrates smooth transition from contraction to expansion

Abstract

We consider a simple cosmological model that includes a long ekpyrotic contraction stage and smooth bounce after it. Ekpyrotic behavior is due to a scalar field with a negative exponential potential, whereas the Galileon field produces bounce. We give an analytical picture of how the bounce occurs within the weak gravity regime, and then perform numerical analysis to extend our results to a non-perturbative regime.