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arXiv · 2403.12522

Hybrid star within $f(\mathcal{G})$ gravity

Pramit Rej
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Abstract

The purpose of this work is to investigate some interesting features of a static anisotropic relativistic stellar object composed of two different types of fluid distributions typically termed as quark matter (QM) and ordinary baryonic matter (OBM) together with Krori-Barua type (KB) {\em ansatz} in the regime of modified $f(\mathcal{G})$ gravity, where $\mathcal{G}$ being the Gauss-Bonnet invariant term. In order to explain the correlation between pressure and matter density for the quark matter distribution within the compact object, we have taken into consideration the well-known MIT bag equation of state (EoS) whereas there is a simple linear correlation between pressure and matter density for ordinary baryonic matter. Furthermore, using graphical representations for varying parameters, the physical credibility of our obtained solutions has been intensively examined by regularity checking of the metric coefficients and matter variables, energy conditions, mass function, and causality conditions. For these analyses, we consider a particular compact stellar candidate 4U 1538-52. Finally, we found that the resulting outcome depicts the viability of the considered hybrid stellar model.

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Pramit Rej. 2024-03-19. Hybrid star within $f(\mathcal{G})$ gravity. https://doi.org/10.1016/j.cjph.2024.02.052

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