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arXiv · 1911.02484

Strange stars in energy-momentum-conserved $f(R,T)$ gravity

Abstract

For the accurate understanding of compact objects such as neutron stars and strange stars, the Tolmann-Openheimer-Volkof (TOV) equation has proved to be of great use. Hence, in this work, we obtain the TOV equation for the energy-momentum-conserved $f(R,T)$ theory of gravity to study strange quark stars. The $f(R,T)$ theory is important, especially in cosmology, because it solves certain incompleteness of the standard model. In general, there is no intrinsic conservation of the energy-momentum tensor in the $f(R,T)$ gravity. Since this conservation is important in the astrophysical context, we impose the condition $\nabla T_{\mu\nu}=0$, so that we obtain a function $f(R,T)$ that implies conservation. This choice of a function $f(R,T)$ that conserves the momentum-energy tensor gives rise to a strong link between gravity and the microphysics of the compact object. We obtain the TOV by taking into account a linear equation of state to describe the matter inside strange stars, such as $p=\omega\rho$ and the MIT bag model $p=\omega(\rho-4B)$. With these assumptions it was possible to derive macroscopic properties of these objects.

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BibTeXRIS

G. A. Carvalho, S. I. dos Santos, Jr., P. H. R. S. Moraes, M. Malheiro. 2019-11-05. Strange stars in energy-momentum-conserved $f(R,T)$ gravity. https://arxiv.org/abs/1911.02484

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