Stability of a viable non-minimal bounce

TL;DR

This paper analyzes the stability of a recently proposed non-minimal bouncing cosmology, demonstrating its robustness against BKL instability and comparing its stability to minimal models, with ekpyrosis identified as the most stable solution.

Contribution

It provides a detailed stability analysis of a viable non-minimal bouncing theory, showing it can evade BKL instability and outperform minimal models in stability.

Findings

Bouncing solution remains stable with an additional barotropic fluid.

The model can evade BKL instability across a wide parameter range.

Ekpyrosis is identified as the most stable scenario.

Abstract

The main difficulties in constructing a viable early Universe bouncing model are: to bypass the observational and theoretical \emph{no-go} theorem, to construct a stable non-singular bouncing phase and perhaps, the major concern of it is to construct a stable attractor solution which can evade the BKL instability as well. In this article, in the homogeneous and isotropic background, we extensively study the stability analysis of the recently announced viable non-minimal bouncing theory in the presence of an additional barotropic fluid and show that, the bouncing solution remains stable and can evade BKL instability for a wide range of the model parameter. We provide the expressions that explain the behavior of the Universe in the vicinity of the required fixed point i.e., the bouncing solution and compare our results with the minimal theory and show that ekpyrosis is the most stable solution in any scenario.