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arXiv · 2607.04596

Neutron stars in $f(Q) = Q +\xi Q^2$ gravity

J. C. N. de Araujo·H. G. M. Fortes
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Abstract

Modified theories of gravity based on the symmetric teleparallel framework have recently attracted considerable attention as viable alternatives to General Relativity. In this context, f(Q) gravity, in which the gravitational interaction is encoded in the nonmetricity scalar Q, provides a consistent geometrical formulation that differs from the standard curvature-based description. In this work, we investigate the structure of neutron stars within a family of f(Q) gravity models by employing realistic equations of state, namely FPS, SLy, ENG and MPA1. Using the covariant formulation of f(Q) gravity, we derive the corresponding Tolman-Oppenheimer-Volkoff equations and apply them to model compact stellar configurations. Numerical integration of the field equations provides the mass-radius relations and the maximum masses supported by each equation of state, enabling a direct comparison with current observational constraints. Furthermore, we analyze the behavior of the nonmetricity scalar both inside and outside the stellar object, providing additional insight into the gravitational structure of compact stars in this framework.

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J. C. N. de Araujo, H. G. M. Fortes. 2026-07-06. Neutron stars in $f(Q) = Q +\xi Q^2$ gravity. https://arxiv.org/abs/2607.04596

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