English

Tidal Deformability of Neutron Stars in Unimodular Gravity

General Relativity and Quantum Cosmology 2022-11-02 v1

Abstract

Unimodular gravity is a modified theory with respect to general relativity by an extra condition that the determinant of the metric is fixed. Especially, if the energy-momentum tensor is not imposed to be conserved separately, a new geometric structure appears with potentially observational signatures. In this paper, we study tidal deformability of compact star in the unimodular gravity under the assumption of non-conserved energy-momentum tensor. Both the electric-type and magnetic-type quadrupole tidal Love numbers are calculated for neutron stars with polytrope model. It is found that the electric-type tidal Love numbers are monotonically increasing, but the magnetic-type ones are decreasing, with the increase of the non-conservation parameter. Compared with the observational data from detected gravitational-wave events, a small negative non-conservation parameter is favored.

Keywords

Cite

@article{arxiv.2211.00278,
  title  = {Tidal Deformability of Neutron Stars in Unimodular Gravity},
  author = {Rui-Xin Yang and Fei Xie and Dao-Jun Liu},
  journal= {arXiv preprint arXiv:2211.00278},
  year   = {2022}
}

Comments

11 pages, 2 figures, accepted for publication in Universe