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arXiv · 2601.00929

Exploring Hybrid Star Models with Quark and Hadronic Matter in $f(Q)$ Gravity

M. Sharif·Madiha Ajmal
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Abstract

In this paper, we develop a model for a static anisotropic hybrid star that includes strange quark matter and hadronic matter. We solve the field equations in the $f(Q)$ gravity framework (where $Q$ is the non-metricity) using the Finch-Skea metric. The relationship between density and pressure for strange quark matter is described using the MIT bag model equation, while for hadronic matter, the radial pressure and density are related by a linear equation of state. We select the compact star EXO 1785-248 and analyze five different values of the coupling constant. To evaluate the physical feasibility of the model, we perform a graphical analysis of key properties, including the metric components, energy density, radial and tangential pressures, anisotropy, gradients, quark matter density and pressure, the equation of state parameter, energy conditions and the mass function. We further examine the stability and equilibrium of the star through parameters such as compactness, redshift, causality conditions, Herrera cracking, the adiabatic index and the Tolman-Oppenheimer-Volkoff equation. We observe that $f(Q)$ gravity effectively describes the macroscopic properties of hybrid stars.

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M. Sharif, Madiha Ajmal. 2026-01-02. Exploring Hybrid Star Models with Quark and Hadronic Matter in $f(Q)$ Gravity. https://arxiv.org/abs/2601.00929

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