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arXiv · 2504.04890

Stellar isotropic model in the symmetric teleparallel equivalent of general relativity theory

G. G. L. Nashed·Amare Abebe
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Abstract

Recently, the theory of symmetric teleparallel equivalent of general relativity (STEGR) has gained much interest in the cosmology and astrophysics community. Within this theory, we discuss the method of deriving a stellar isotropic model. In this respect, we implement the equations of motion of STEGR theory to a spacetime that is symmetric in a spherical manner, resulting in a set of nonlinear differential equations with more unknowns than equations. To solve this issue, we assume a special form of $g_{tt}$, and suppose a null value of the anisotropy to obtain the form of $g_{rr}$. We then investigate the possibility of obtaining an isotropic stellar model consistent with observational data. To test the stability of our model, we apply the adiabatic index and the Tolman-Oppenheimer-Volkoff equation. Furthermore, we examine our model using different observed values of radii and masses of pulsars, showing that all of them fit in a consistent way.

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G. G. L. Nashed, Amare Abebe. 2025-04-07. Stellar isotropic model in the symmetric teleparallel equivalent of general relativity theory. https://doi.org/10.1016/j.aop.2025.169958

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