Stellar Hydrostatic Equilibrium Compact Structures in $f(\mathcal{G},T)$ Gravity

TL;DR

This study explores how a modified gravity model, involving the Gauss-Bonnet invariant and energy-momentum trace, affects the structure and properties of neutron and strange stars, revealing potential for increased stellar mass.

Contribution

It derives hydrostatic equilibrium equations in $f( ext{G},T)$ gravity and analyzes their impact on compact star characteristics, a novel approach in this gravity framework.

Findings

Stellar mass increases with higher $ ext{T}$ coupling $\\lambda$.

Total stellar radius decreases as $\\lambda$ increases.

Maximum stellar mass can surpass observational limits.

Abstract

In this paper, stellar hydrostatic equilibrium configuration of the compact stars (neutron stars and strange stars) has been studied for $f(\mathcal{G},T)$ gravity model, with $\mathcal{G}$ and $T$ being the Gauss-Bonnet invariant and the trace of energy momentum tensor, respectively. After having derived the hydrostatic equilibrium equations for $f(\mathcal{G},T)$ gravity, the fluid pressure for the neutron stars and the strange stars has been computed by implying two equation of state models corresponding to two different existing compact stars. For the $f(\mathcal{G},T)=\alpha{\mathcal{G}^n+\lambda{T}}$ gravity model, with $\alpha$, $n$, and $\lambda$ being some specific constants, substantial change in the behavior of the physical attributes of the compact stars like the energy density, pressure, stellar mass, and total radius has been noted with the corresponding change in $\lambda$ values. Meanwhile, it has been shown that for some fixed central energy density and with increasing values of $\lambda$, the stellar mass both for the neutron stars and the strange stars increases, while the total stellar radius $R$ exhibits the opposite behavior for both of the compact stars. It is concluded that for this $f(\mathcal{G},T)$ stellar model, the maximum stellar mass can be boosted above the observational limits.