Cosmographic analysis of a closed bouncing universe with the varying cosmological constant in $f(R,T)$ gravity

TL;DR

This paper explores a closed universe model with a varying cosmological constant in $f(R,T)$ gravity, demonstrating a non-singular bounce consistent with observations and analyzing its stability and accelerated expansion.

Contribution

It introduces a matter bounce model in $f(R,T)$ gravity with a varying cosmological constant, avoiding null energy condition violations and aligning with recent observational data.

Findings

Closed universe with negative pressure is compatible with observations.

The model exhibits a non-singular bounce without violating the null energy condition.

Cosmographic parameters explain the universe's accelerated expansion.

Abstract

Modeling of matter bounce in $f(R,T)$ gravity has been presented with no violation of the null energy condition. Only a closed universe with negative pressure is allowed in good agreement with some recent observations which favor a universe with positive curvature. Our results agree with some recent works in which a combination of positive curvature and vacuum energy leads to non-singular bounces with no violation of the null energy condition. The stability of the model has been discussed. The cosmographic parameters are developed for the derived model to explain the accelerated expansion of the universe.