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arXiv · 2407.03617

Physical Analysis of Spherical Stellar Structures in $f(\mathrm{Q},\mathrm{T})$ Theory

M. Zeeshan Gul·M. Sharif·Adeeba Arooj
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Abstract

This paper explores the viability and stability of compact stellar objects characterized by anisotropic matter in the framework of $f(\mathrm{Q},\mathrm{T})$ theory, where $\mathrm{Q}$ denotes non-metricity and $\mathrm{T}$ represents the trace of the energy-momentum tensor. We consider a specific model of this theory to obtain explicit expressions for the field equations governing the behavior of matter and geometry in this context. Furthermore, the Karmarkar condition is employed to assess the configuration of static spherically symmetric structures. The values of unknown constants in the metric potentials are determined through matching conditions of the interior and exterior spacetimes. Various physical quantities such as fluid parameters, energy constraints, equation of state parameters, mass, compactness and redshift are graphically analyzed to evaluate the viability of the considered compact stars. The Tolman-Oppenheimer-Volkoff equation is used to examine the equilibrium state of the stellar models. Moreover, the stability of the proposed compact stars is investigated through sound speed and adiabatic index methods. This study concludes that the proposed compact stars analyzed in this theoretical framework are viable and stable, as all the required conditions are satisfied.

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M. Zeeshan Gul, M. Sharif, Adeeba Arooj. 2024-07-04. Physical Analysis of Spherical Stellar Structures in $f(\mathrm{Q},\mathrm{T})$ Theory. https://doi.org/10.1007/s10714-024-03234-8

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