Neutron stars in the bumblebee theory of gravity

TL;DR

This paper investigates neutron star solutions within the bumblebee gravity model, a Lorentz-violating vector-tensor theory, revealing diverse stellar configurations and deriving preliminary observational constraints.

Contribution

It provides the first comprehensive calculation of neutron star solutions in the bumblebee gravity model, exploring effects of different coupling constants and constraining vector field values.

Findings

Discovery of vectorized neutron stars and divergent mass solutions.

Constraints on asymptotic vector field values based on stellar radius observations.

Rich theoretical landscape of neutron star configurations in bumblebee gravity.

Abstract

Recently, theoretical studies on the bumblebee gravity model, a nonminimally-coupled vector-tensor theory that violates the Lorentz symmetry, have flourished, with a simultaneous increase in the utilization of observations to impose constraints. The static spherical solutions of neutron stars (NSs) in the bumblebee theory are calculated comprehensively in this work. These solutions with different coupling constants reveal a rich theoretical landscape for NSs, including vectorized NSs and NSs with finite radii but divergent masses. With these solutions, preliminary constraints on the asymptotic vector field values are obtained through restrictions on the stellar radius.