Regular Black Strings and BTZ Black Hole in Unimodular Gravity Supported by Maxwell Fields

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Alencar, G., Borralho, V. H. U.
Format: Preprint
Veröffentlicht: 2026
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866914505566453760
author Alencar, G.
Borralho, V. H. U.
author_facet Alencar, G.
Borralho, V. H. U.
contents In this work, we obtain a Maxwell source for regular black string and BTZ black hole using the framework of unimodular gravity. This type of alternative to general relativity imposes an additional condition on the spacetime volume element, namely that it is constant, $\det(g_{μν}) = g_0$, and thus restricts diffeomorphism invariance to volume-preserving transformations. In this procedure, the cosmological constant does not appear directly in the action, but rather as an integration constant of the field equations. By using the non-conservation of the energy-momentum tensor, we show that the integration constant becomes a function $Λ(x)$, which is interpreted as a vacuum contribution depending on the radial coordinate, in our case. From the definition of the geometric function $H(r)$, we verify the validity of Maxwell electrodynamics as a source for the solutions and compute the vacuum contribution $Λ(r)$ that supports the solutions.
format Preprint
id arxiv_https___arxiv_org_abs_2604_00078
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Regular Black Strings and BTZ Black Hole in Unimodular Gravity Supported by Maxwell Fields
Alencar, G.
Borralho, V. H. U.
General Relativity and Quantum Cosmology
In this work, we obtain a Maxwell source for regular black string and BTZ black hole using the framework of unimodular gravity. This type of alternative to general relativity imposes an additional condition on the spacetime volume element, namely that it is constant, $\det(g_{μν}) = g_0$, and thus restricts diffeomorphism invariance to volume-preserving transformations. In this procedure, the cosmological constant does not appear directly in the action, but rather as an integration constant of the field equations. By using the non-conservation of the energy-momentum tensor, we show that the integration constant becomes a function $Λ(x)$, which is interpreted as a vacuum contribution depending on the radial coordinate, in our case. From the definition of the geometric function $H(r)$, we verify the validity of Maxwell electrodynamics as a source for the solutions and compute the vacuum contribution $Λ(r)$ that supports the solutions.
title Regular Black Strings and BTZ Black Hole in Unimodular Gravity Supported by Maxwell Fields
topic General Relativity and Quantum Cosmology
url https://arxiv.org/abs/2604.00078