Electromagnetic properties of Kerrantide Sitter black holes
Abstract
We examine the electromagnetic properties of Kerrantide Sitter (KerrAdS) black holes in four and higher spacetime dimensions. Assuming that the black holes may carry a test electric charge we show that the Killing oneform which represents the difference between the timelike generators in the spacetime and in the reference background can be used as a potential oneform for the associated electromagnetic field. In four dimensions the potential oneform and the KerrAdS metric with properly rescaled mass parameter solve the EinsteinMaxwell equations, thereby resulting in the familiar KerrNewmanAdS solution. We solve the quartic equation governing the location of the event horizons of the KerrNewmanAdS black holes and present closed analytic expressions for the radii of the horizons. We also compute the gyromagnetic ratio for these black holes and show that it corresponds to g=2 just as for ordinary black holes in asymptotically flat spacetime. Next, we compute the gyromagnetic ratio for the KerrAdS black holes with a single angular momentum and with a test electric charge in all higher dimensions. The gyromagnetic ratio crucially depends on the dimensionless ratio of the rotation parameter to the curvature radius of the AdS background. At the critical limit, when the boundary Einstein universe ismore »
 Authors:
 Feza Guersey Institute, P. K. 6 Cengelkoey, 34684 Istanbul (Turkey)
 Publication Date:
 OSTI Identifier:
 21020410
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 8; Other Information: DOI: 10.1103/PhysRevD.75.084041; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ANGULAR MOMENTUM; ANGULAR VELOCITY; BLACK HOLES; COSMOLOGY; DE SITTER GROUP; EINSTEINMAXWELL EQUATIONS; ELECTRIC CHARGES; ELECTROMAGNETIC FIELDS; GYROMAGNETIC RATIO; KERR METRIC; MASS; MATHEMATICAL SOLUTIONS; POTENTIALS; ROTATION; SPACETIME; UNIVERSE
Citation Formats
Aliev, Alikram N. Electromagnetic properties of Kerrantide Sitter black holes. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVD.75.084041.
Aliev, Alikram N. Electromagnetic properties of Kerrantide Sitter black holes. United States. doi:10.1103/PHYSREVD.75.084041.
Aliev, Alikram N. Sun .
"Electromagnetic properties of Kerrantide Sitter black holes". United States.
doi:10.1103/PHYSREVD.75.084041.
@article{osti_21020410,
title = {Electromagnetic properties of Kerrantide Sitter black holes},
author = {Aliev, Alikram N.},
abstractNote = {We examine the electromagnetic properties of Kerrantide Sitter (KerrAdS) black holes in four and higher spacetime dimensions. Assuming that the black holes may carry a test electric charge we show that the Killing oneform which represents the difference between the timelike generators in the spacetime and in the reference background can be used as a potential oneform for the associated electromagnetic field. In four dimensions the potential oneform and the KerrAdS metric with properly rescaled mass parameter solve the EinsteinMaxwell equations, thereby resulting in the familiar KerrNewmanAdS solution. We solve the quartic equation governing the location of the event horizons of the KerrNewmanAdS black holes and present closed analytic expressions for the radii of the horizons. We also compute the gyromagnetic ratio for these black holes and show that it corresponds to g=2 just as for ordinary black holes in asymptotically flat spacetime. Next, we compute the gyromagnetic ratio for the KerrAdS black holes with a single angular momentum and with a test electric charge in all higher dimensions. The gyromagnetic ratio crucially depends on the dimensionless ratio of the rotation parameter to the curvature radius of the AdS background. At the critical limit, when the boundary Einstein universe is rotating at the speed of light, it tends to g=2 irrespective of the spacetime dimension. Finally, we consider the case of a fivedimensional KerrAdS black hole with two angular momenta and show that it possesses two distinct gyromagnetic ratios in accordance with its two orthogonal twoplanes of rotation. In the special case of two equal angular momenta, the two gyromagnetic ratios merge into one leading to g=4 at the maximum angular velocities of rotation.},
doi = {10.1103/PHYSREVD.75.084041},
journal = {Physical Review. D, Particles Fields},
number = 8,
volume = 75,
place = {United States},
year = {Sun Apr 15 00:00:00 EDT 2007},
month = {Sun Apr 15 00:00:00 EDT 2007}
}

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