Tidal Deformability of Neutron Stars in Unimodular Gravity
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 will appear with potential observational signat...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2022-11-01
|
| Series: | Universe |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2218-1997/8/11/576 |
| _version_ | 1797466339578740736 |
|---|---|
| author | Rui-Xin Yang Fei Xie Dao-Jun Liu |
| author_facet | Rui-Xin Yang Fei Xie Dao-Jun Liu |
| author_sort | Rui-Xin Yang |
| collection | DOAJ |
| description | 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 will appear with potential observational signatures. In this paper, we study the tidal deformability of a compact star in unimodular gravity under the assumption of a non-conserved energy-momentum tensor. Both the electric-type and magnetic-type quadrupole tidal Love numbers are calculated for neutron stars using the 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 in the non-conservation parameter. Compared with the observational data from the detected gravitational-wave events, a small negative non-conservation parameter is favored. |
| first_indexed | 2024-03-09T18:35:31Z |
| format | Article |
| id | doaj.art-b1b2b9d634ef45d994ad445010d945ab |
| institution | Directory Open Access Journal |
| issn | 2218-1997 |
| language | English |
| last_indexed | 2024-03-09T18:35:31Z |
| publishDate | 2022-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Universe |
| spelling | doaj.art-b1b2b9d634ef45d994ad445010d945ab2023-11-24T07:12:13ZengMDPI AGUniverse2218-19972022-11-0181157610.3390/universe8110576Tidal Deformability of Neutron Stars in Unimodular GravityRui-Xin Yang0Fei Xie1Dao-Jun Liu2Department of Physics and Center for Astrophysics, Shanghai Normal University, Shanghai 200234, ChinaDepartment of Physics and Center for Astrophysics, Shanghai Normal University, Shanghai 200234, ChinaDepartment of Physics and Center for Astrophysics, Shanghai Normal University, Shanghai 200234, ChinaUnimodular 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 will appear with potential observational signatures. In this paper, we study the tidal deformability of a compact star in unimodular gravity under the assumption of a non-conserved energy-momentum tensor. Both the electric-type and magnetic-type quadrupole tidal Love numbers are calculated for neutron stars using the 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 in the non-conservation parameter. Compared with the observational data from the detected gravitational-wave events, a small negative non-conservation parameter is favored.https://www.mdpi.com/2218-1997/8/11/576tidal Love numberneutron starunimodular gravity |
| spellingShingle | Rui-Xin Yang Fei Xie Dao-Jun Liu Tidal Deformability of Neutron Stars in Unimodular Gravity Universe tidal Love number neutron star unimodular gravity |
| title | Tidal Deformability of Neutron Stars in Unimodular Gravity |
| title_full | Tidal Deformability of Neutron Stars in Unimodular Gravity |
| title_fullStr | Tidal Deformability of Neutron Stars in Unimodular Gravity |
| title_full_unstemmed | Tidal Deformability of Neutron Stars in Unimodular Gravity |
| title_short | Tidal Deformability of Neutron Stars in Unimodular Gravity |
| title_sort | tidal deformability of neutron stars in unimodular gravity |
| topic | tidal Love number neutron star unimodular gravity |
| url | https://www.mdpi.com/2218-1997/8/11/576 |
| work_keys_str_mv | AT ruixinyang tidaldeformabilityofneutronstarsinunimodulargravity AT feixie tidaldeformabilityofneutronstarsinunimodulargravity AT daojunliu tidaldeformabilityofneutronstarsinunimodulargravity |