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arXiv · 2403.03026

Polytropic stellar structure in 5$\mathcal{D}$ Einstein-Gauss-Bonnet gravity

Akashdip Karmakar·Ujjal Debnath·Pramit Rej
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Abstract

Polytropic stars are useful tools for learning about stellar structure without the complexity of comprehensive stellar models. These models rely on a certain power-law correlation between the star's pressure and density. This paper proposes a polytropic star model to investigate some new features in the context of $5\mathcal{D}$ Einstein-Gauss-Bonnet (EGB) gravity using the Finch-Skea {\em ansatz} [{\em M. R. Finch and J. E. Skea, Classical and Quantum Gravity 6, 467 (1989)}]. Analytical results are better described by graphical representations of the physical parameters for various values of the Gauss-Bonnet coupling constant $\alpha$. The solution for a specific compact object, EXO 1785-248, with radius $\mathfrak{R} = 8.849_{-0.04}^{+0.04}$ km and mass $\mathcal{M} = 1.3 \pm 0.02~\mathcal{M}_{\odot}$, is shown here. We analyze the essential physical attributes of the star, which reveal the influence of the coupling parameter $\alpha$ on the values of the parameters. Ultimately, we conclude that our current model is realistic because it satisfies all the physical criteria for an acceptable model.

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Akashdip Karmakar, Ujjal Debnath, Pramit Rej. 2024-03-05. Polytropic stellar structure in 5$\mathcal{D}$ Einstein-Gauss-Bonnet gravity. https://doi.org/10.1016/j.cjph.2024.05.037

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