Compact stellar model in higher torsion gravitational theory

TL;DR

This paper develops a compact stellar model within higher torsion gravitational theory, deriving analytic solutions for stellar structure affected by torsion and demonstrating its stability and physical viability.

Contribution

It introduces a new spherically symmetric stellar model in quadratic $f(T)$ gravity using the Krori-Barua ansatz, highlighting effects of torsion on stellar properties.

Findings

Model satisfies physical conditions for realistic stars

Derived analytic expressions for density and pressures

Model remains stable under TOV and adiabatic index analyses

Abstract

In this study, we address the issue of a spherically symmetrical interior solution to the quadratic form of $f\mathcal{(T)}=\mathcal{T}+\epsilon \mathcal{T}^2$ gravitational theory using a physical tetrad that provides vanishing components of the off-components of the field equation, in contrast to what exists in the current literature. To be able to formulate the resulting differential equation in a closed form, we employ the Krori-Barua (KB) ansatz. Using the KB spacetime form, we derive the analytic form of the energy-density, radial, and tangential pressures and the anisotropic form. All of these quantities are affected by the dimensional parameter $\epsilon$, which causes them to have a noted difference from those given in the frame of Einstein general relativity. The derived model of this study exhibits a non-trivial form of torsion scalar, and it also contains three constants that we drew from the matching of the boundary condition with a line element that also features a non-trivial form of torsion scalar. Having established the physical conditions that are needed for any real stellar, we check our model and show in detail that it bypasses all of these. Finally, we analyze the model's stability utilizing the Tolman-Oppenheimer-Volkoff equation and adiabatic index and show that our model satisfies these.