Research ArticleNo Access

Anisotropic decoupled spheres in $f (G, T)$ $f (G, T)$ gravity

M. Sharif

https://orcid.org/0000-0001-6845-3506

Department of Mathematics and Statistics, The University of Lahore, 1-KM Defence Road Lahore, Pakistan

E-mail Address: msharif.math@pu.edu.pk

Corresponding author.

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and

K. Hassan

Department of Mathematics, University of the Punjab, Quaid-e-Azam Campus, Lahore 54590, Pakistan

E-mail Address: komalhassan3@gmail.com

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https://doi.org/10.1142/S021988782250150XCited by:5 (Source: Crossref)

Abstract

This paper aims to determine the anisotropic solutions for static spherically symmetric spacetime via gravitational decoupling technique in the context of $f (G, T)$ $f (G, T)$ gravity, where $G$ $G$ indicates the Gauss–Bonnet term and $T$ $T$ represents trace of the energy-momentum tensor. The additional source, present alongside the isotropic seed source in the sphere, induces anisotropy in the system. In order to decouple the two sources, we impose a minimal geometric deformation on the radial metric component which gives rise to two sets. The first array represents the isotropic system while the second set corresponds to the anisotropic structure. In order to determine the solution of first set, we use the metric potentials of the Tolman V spacetime while two solutions of the second set are extracted with the help of two constraints on the components of the additional source. These solutions are combined with the solution of the first set to formulate two extensions of Tolman V spacetime. The matching between the interior and exterior geometries yields the values of unknown constants. Furthermore, the viability and stability of the obtained solutions are checked for different values of the parameters. It is concluded that both solutions are viable and the first solution is stable as well, while the second solution shows unstable behavior.

Keywords:

PACS: 04.20.Jb, 04.40.Dg, 04.50.Kd

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