Bouncing Eddington-inspired Born-Infeld cosmologies: an alternative to Inflation ?

TL;DR

This paper explores bouncing cosmologies within Eddington-inspired Born-Infeld gravity, showing they can avoid singularities and serve as an alternative to inflation for early universe modeling.

Contribution

It generalizes previous models to include arbitrary fluid equations of state, demonstrating bounce conditions and singularity avoidance in Eddington-inspired Born-Infeld cosmology.

Findings

Bounces can occur for positive  with time-dependent w

The model avoids tensor singularities

Potential as an inflation alternative

Abstract

We study the dynamics of a homogeneous and isotropic Friedmann-Robertson-Walker universe in the context of the Eddington-inspired Born-Infeld theory of gravity. We generalize earlier results, obtained in the context of a radiation dominated universe, to account for the evolution of a universe permeated by a perfect fluid with an arbitrary equation of state parameter $w$. We show that a bounce may occur for $\kappa >0$, if $w$ is time-dependent, and we demonstrate that it is free from tensor singularities. We argue that Eddington-inspired Born-Infeld cosmologies may be a viable alternative to the inflationary paradigm as a solution to fundamental problems of the standard cosmological model.