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arXiv · 2201.08391

Anisotropic strange stars in Einstein Gauss-Bonnet Gravity with Finch-Skea metric

Abstract

We obtain a class of new anisotropic relativistic solution in Einstein Gauss-Bonnet (EGB) gravity with Finch-Skea metric in hydrostatic equilibrium. The relativistic solutions are employed to construct anisotropic stellar models for strange star with MIT Bag equation of state $ p_{r}= \frac{1}{3} \left( \rho - 4 B_{g}\right)$, where $B_{g}$ is the Bag constants. Considering the mass and radius of a known star PSR J0348+0432 we construct stellar models in the framework of higher dimensions. We also predict the mass and radius of stars for different model parameters. The Gauss-Bonnet coupling term ($\alpha$) plays an important role in determining the density, pressure, anisotropy profiles and other features. The stability of the stellar models are probed analyzing the different energy conditions, variation of sound speed and adiabatic stability conditions inside the star. The central density and pressure of a star in EGB gravity are found to have higher values compared to that one obtains in Einstein gravity ($\alpha =0$). We also explore the effect of extra dimensions for the physical features of a compact object. For this we consider $D=5$ and $D=6$ to obtain a realistic stellar model and found that in the formal case both positive and negative values of $\alpha$ are allowed. But in the later case, only $\alpha <0$ permits compact object in the Finch-Skea metric. We determine the best fit values of the model parameters for a number of observed stars for acceptable stellar models.

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BibTeXRIS

Sagar Dey, Bikash Chandra Paul. 2022-01-20. Anisotropic strange stars in Einstein Gauss-Bonnet Gravity with Finch-Skea metric. https://arxiv.org/abs/2201.08391

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