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arXiv · 2402.15395

Hydrostatic equilibrium configurations of neutron stars in the $f(R,\mathcal{L},T)$ gravity theory

J. A. S. Fortunato·P. H. R. S. Moraes·E. Brito·J. G. de Lima Júnior·T. S. Guerini
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Abstract

In the present work, we obtain the hydrostatic equilibrium configurations of neutron stars in the recently proposed $f(R,\mathcal{L},T)$ theory of gravity, for which $R$ is the Ricci scalar, $\mathcal{L}$ is the matter lagrangian density, $T$ is the trace of the energy-momentum tensor and $f$ is a function of the argument. This theory emerges in the present literature as a generalized geometry-matter coupling theory of gravity. We derive the Tolman-Oppenheimer-Volkoff-like equation for a particular functional form of the $f(R,\mathcal{L},T)$ function. Our solutions are obtained from realistic equations of state describing matter inside neutron stars. We obtain stable solutions for neutron stars and we show that for some values of the free parameter of the theory it is possible to be in agreement with both NICER and LIGO/Virgo observational data.

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J. A. S. Fortunato, P. H. R. S. Moraes, E. Brito, J. G. de Lima Júnior, T. S. Guerini. 2024-02-23. Hydrostatic equilibrium configurations of neutron stars in the $f(R,\mathcal{L},T)$ gravity theory. https://arxiv.org/abs/2402.15395

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