Bouncing cosmology in modified gravity with higher-order curvature terms

TL;DR

This paper investigates a bouncing universe scenario within a modified gravity framework incorporating higher-order curvature terms, demonstrating the avoidance of initial singularity and crossing of the phantom divide.

Contribution

It introduces a reconstruction technique for a power-law Hubble parameter in modified gravity with higher-order curvature, showing conditions for a non-singular bounce.

Findings

Bouncing criteria are satisfied, avoiding the initial singularity.

The equation of state parameter crosses the phantom divide.

Extremal acceleration occurs at the bounce point.

Abstract

A bouncing scenario of a flat homogeneous and isotropic universe is explored by using the reconstruction technique for the power-law parametrization of the Hubble parameter in a modified gravity theory with higher-order curvature and trace of the energy-momentum tensor terms. It is demonstrated that bouncing criteria are satisfied so that the cosmological initial singularity can be avoided. In addition, it is shown that the equation of state parameter crosses the line of the phantom divide. In the present scenario, the universe is filled with perfect fluid around the bouncing point, in which the universe becomes highly unstable and a big bounce can be realized. Furthermore, it is found that extremal acceleration occurs at the bouncing point.