A cyclic non-singular universe from Gauss-Bonnet and superstring corrections

Abstract

In this study, we have constructed a viable cosmological model characterized by the presence of the Gauss-Bonnet four-dimensional invariant, higher-order corrections to the low energy effective action motivated from heterotic superstring theory and a general exponential potential comparable to those obtained in higher dimensional supergravities. The field equations were studied by assuming a particular relation between the Hubble parameter and the time derivative of the scalar field. It was observed that, for specific relations between the free parameters in the theory, the universe is cyclic, expands and contracts alternately without singularity with an equation of state oscillating around -1. The model is found to fit the recent astrophysical data.