A periodic varying deceleration parameter in $f(R,T)$ gravity

TL;DR

This paper investigates the accelerated expansion of the universe using a modified gravity model, deriving exact solutions with a periodic deceleration parameter and analyzing the oscillatory behavior of cosmological parameters.

Contribution

It introduces a novel periodic deceleration parameter in $f(R,T)$ gravity and derives exact solutions, exploring cosmic transit and energy condition violations.

Findings

Oscillatory behavior of the equation of state parameter.

Violation of energy-momentum conservation in the model.

Periodic energy conditions for various parameters.

Abstract

The phenomenon of accelerated expansion of the present universe and a cosmic transit aspect is explored in the framework of a modified gravity theory known as $f(R,T)$ gravity (where $R$ is the Ricci scalar and $T$ is the trace of the energy momentum tensor of the matter content). The cosmic transit phenomenon signifies a signature flipping behaviour of the deceleration parameter. We employ a periodic varying deceleration parameter and obtained the exact solution of field equations. The dynamical features of the model including the oscillatory behaviour of the EOS parameter are studied. We have also explored the obvious violation of energy momentum conservation in $f(R,T)$ gravity. The periodic behaviour of energy conditions for the model are also discussed with a wide range of the free parameters.