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arXiv · 2412.03219

Neutron star in Logarithmic model of Cartan $F(R)$ gravity

Hiroki Sakamoto·Masahiko Taniguchi
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Abstract

Cartan $F(R)$ gravity introduces the equivalent scalar-tensor theory by extending the gravity sector. From the solution of the modified Cartan equation leads to the interaction with the scalar field and the fermion. We derived the effective potential of the scalar field using the auxiliary field method, which is commonly used in studies of spontaneous chiral symmetry breaking. Using this effective potential we investigated the mass-radius relation of neutron star to solve the Tolman-Oppenheimer-Volkoff equation. By the numerical computation, we found that the contribution of the scalar field increases the mass of a neutron star. This could give theoretical plausibility to the current observations.

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Hiroki Sakamoto, Masahiko Taniguchi. 2024-12-04. Neutron star in Logarithmic model of Cartan $F(R)$ gravity. https://arxiv.org/abs/2412.03219

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