An anisotropic version of Tolman VII solution in $f(R,T)$ gravity via Gravitational Decoupling MGD Approach

TL;DR

This paper develops an anisotropic stellar model within $f(R,T)$ gravity using the MGD approach, matching observational data of compact stars and analyzing its physical and stability properties.

Contribution

It introduces a novel anisotropic solution in $f(R,T)$ gravity via gravitational decoupling, extending the Tolman VII solution with observational validation.

Findings

Energy conditions are satisfied for all three star models.

The solution is stable under causality and cracking criteria.

The model fits observational data of specific compact stars.

Abstract

In this work, we have adopted gravitational decoupling by Minimal Geometric Deformation (MGD) approach and have developed an anisotropic version of well-known Tolman VII isotropic solution in the framework of $f(R, T)$ gravity, where $R$ is Ricci scalar and $T$ is trace of energy momentum tensor. The set of field equations has been developed with respect to total energy momentum tensor, which combines effective energy momentum tensor in $f(R,T)$ gravity and additional source $\phi_{ij}$. Following MGD approach, the set of field equations has been separated into two sections. One section represents $f(R, T)$ field equations, while the other is related to the source $\phi_{ij}$. The matching conditions for inner and outer geometry have also been discussed and an anisotropic solution has been developed using mimic constraint for radial pressure. In order to check viability of the solution, we have considered observation data of three different compact star models, named PSR J1614-2230, PSR 1937+21 and SAX J1808.4-3658 and have discussed thermodynamical properties analytically and graphically. The energy conditions are found to be satisfied for the three compact stars. The stability analysis has been presented through causality condition and Herrera's cracking concept, which ensures physical acceptability of the solution.