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arXiv · 2001.06644

Stellar Structures in $f(\mathcal{G})$ Gravity with Tolman-Kuchowicz Spacetime

M. Farasat Shamir·Tayyaba Naz
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Abstract

This paper is devoted to explore some relativistic configurations of stellar objects for static spherically symmetric structures in the context of modified $f(\mathcal{G})$ gravity, by exploiting the Tolman-Kuchowicz spacetime [1,2]. We develop the equations of motion for spherically symmetric spacetime in the presence of anisotropic matter distribution by considering the physically valid expressions of the metric potentials, $\nu=Br^2+2lnC$ and $\lambda=ln(1 + ar^2+br^4)$. To attain the values of the unknown constants we consider the observational data of $Cen~ X-3$, $EXO ~1785-248$ and $LMC~ X-4$ star models. Further, by using evaluated form of the solutions we provide many aspects which are described by the physical status like effective energy density, components of radial and transverse pressure, energy conditions, stability against equilibrium of the forces, speed of sound, mass-radius relation, surface redshift, compactness parameter, adiabatic index and anisotropic measurement. It is observed that all these features follow physically accepted patterns and the resulting outcome is in the experimental range which depicts the viability of our presented $f(\mathcal{G})$ gravity models.

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M. Farasat Shamir, Tayyaba Naz. 2020-01-18. Stellar Structures in $f(\mathcal{G})$ Gravity with Tolman-Kuchowicz Spacetime. https://doi.org/10.1016/j.dark.2020.100472

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