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arXiv · 2509.02641

Impact of Pulsar SAX J1748.9-2021 Observations on $f(\mathcal{Q}, \mathbb{T})$ Gravity

M. Sharif·Iqra Ibrar
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Abstract

The main objective of this study is to investigate the viability and stability of a pulsar filled with anisotropic matter in $f(\mathcal{Q}, \mathbb{T})$ gravity, where $\mathcal{Q}$ represents non-metricity and $\mathbb{T}$ is the trace of the energy-momentum tensor. In this context, we employ non-singular solution and a particular model of this gravity. We use junction conditions to evaluate unknown constants in the metric coefficients. Observations from the pulsar SAX J1748.9-2021 star are employed to validate the model, producing stable configurations that address both geometric and physical characteristics. This framework establishes relationships between various physical quantities, including fluid parameters, anisotropy, mass-radius relation, redshift, the Zeldovich condition, energy conditions, causality conditions, adiabatic index, Tolman-Oppenheimer-Volkoff equation, the equation of state parameter, and compactness. Our findings confirm the viability and stability of the proposed pulsar star in this theoretical framework.

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M. Sharif, Iqra Ibrar. 2025-09-02. Impact of Pulsar SAX J1748.9-2021 Observations on $f(\mathcal{Q}, \mathbb{T})$ Gravity. https://arxiv.org/abs/2509.02641

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