scholarly journals Dyons and dyonic black holes insu(N)Einstein-Yang-Mills theory in anti–de Sitter spacetime

2016 ◽  
Vol 93 (6) ◽  
Author(s):  
Ben L. Shepherd ◽  
Elizabeth Winstanley
Keyword(s):  
Black Holes ◽  
De Sitter Spacetime ◽  
De Sitter ◽  
Yang Mills ◽  
Sitter Spacetime

scholarly journals HIGHER DIMENSIONAL INHOMOGENEOUS DUST COLLAPSE AND COSMIC CENSORSHIP

2002 ◽  
Vol 17 (20) ◽  
pp. 2747-2747
Author(s):  
A. BEESHAM
Keyword(s):  
Black Holes ◽  
Cosmic Censorship ◽  
De Sitter Spacetime ◽  
De Sitter ◽  
Naked Singularities ◽  
Singularity Theorems ◽  
Sitter Spacetime ◽  
Higher Dimensional ◽  
Cosmic Censorship Hypothesis ◽  
Strong Curvature

The singularity theorems of general relativity predict that gravitational collapse finally ends up in a spacetime singularity1. The cosmic censorship hypothesis (CCH) states that such a singularity is covered by an event horizon2. Despite much effort, there is no rigorous formulation or proof of the CCH. In view of this, examples that appear to violate the CCH and lead to naked singularities, in which non-spacelike curves can emerge, rather than black holes, are important to shed more light on the issue. We have studied several collapse scenarios which can lead to both situations3. In the case of the Vaidya-de Sitter spacetime4, we have shown that the naked singularities that arise are of the strong curvature type. Both types of singularities can also arise in higher dimensional Vaidya and Tolman-Bondi spacetimes, but black holes are favoured in some sense by the higher dimensions. The charged Vaidya-de Sitter spacetime also exhibits both types of singularities5.

scholarly journals Tunneling across dilaton coupled black holes in anti de Sitter spacetime

2011 ◽  
Vol 696 (1-2) ◽  
pp. 167-172 ◽  
Author(s):  
Tanwi Ghosh ◽  
Soumitra SenGupta
Keyword(s):  
Black Holes ◽  
De Sitter Spacetime ◽  
De Sitter ◽  
Sitter Spacetime

scholarly journals NONSTATIC CHARGED BTZ-LIKE BLACK HOLES IN N+1 DIMENSIONS

2012 ◽  
Vol 21 (03) ◽  
pp. 1250022 ◽  
Author(s):  
SUSHANT G. GHOSH
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Gravitational Collapse ◽  
Naked Singularity ◽  
De Sitter Spacetime ◽  
De Sitter ◽  
Btz Black Hole ◽  
Sitter Spacetime ◽  
Apparent Horizons ◽  
Sitter Background

We find an exact nonstatic charged BTZ-like solutions, in (N+1)-dimensional Einstein gravity in the presence of negative cosmological constant and a nonlinear Maxwell field defined by a power s of the Maxwell invariant, which describes the gravitational collapse of charged null fluid in an anti-de Sitter background. Considering the situation that a charged null fluid injects into the initially an anti-de Sitter spacetime, we show that a black hole form rather than a naked singularity, irrespective of spacetime dimensions, from gravitational collapse in accordance with cosmic censorship conjecture. The structure and locations of the apparent horizons of the black holes are also determined. It is interesting to see that, in the static limit and when N = 2, one can retrieve 2+1 BTZ black hole solutions.

CHARGED BLACK HOLES IN ASYMPTOTICALLY ANTI-DE SITTER SPACETIME

2000 ◽  
Vol 14 (19n20) ◽  
pp. 1953-1966 ◽  
Author(s):  
P. MITRA
Keyword(s):  
Black Holes ◽  
Functional Integral ◽  
De Sitter Spacetime ◽  
De Sitter ◽  
One Dimensional ◽  
Sitter Spacetime ◽  
Zero Entropy ◽  
Usual Case ◽  
The One ◽  
Extremal Black Holes

Unlike the extremal Reissner–Nordström black hole in ordinary spacetime, the one in anti-de Sitter spacetime is a minimum of action and has zero entropy if (functional integral) quantization is carried out after extremalization. However, if extremalization is carried out after quantization, then the entropy is a quarter of the area as in the usual case. This is because the functional integral is dominated by non-extremal configurations of lower action. However, some special non-extremal black holes have higher action and may decay into extremal configurations. An attempt is also made to see if the anti-de Sitter version can be described by a microscopic model consisting of a one-dimensional gas of massless particles as in the usual case. Such a description is possible only in the limit of vanishing cosmological constant.

scholarly journals Regular Bardeen Black Holes in Anti-de Sitter Spacetime versus Kerr Black Holes through Particle Dynamics

Galaxies ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 63
Author(s):  
Bakhtiyor Narzilloev ◽  
Javlon Rayimbaev ◽  
Ahmadjon Abdujabbarov ◽  
Bobomurat Ahmedov
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Magnetic Charge ◽  
Particle Dynamics ◽  
Kerr Metric ◽  
De Sitter Spacetime ◽  
De Sitter ◽  
Sitter Spacetime ◽  
Test Particles ◽  
Charge Parameter

In this work, test particle dynamics around a static regular Bardeen black hole (BH) in Anti-de Sitter spacetime has been studied. It has been shown for neutral test particles that parameters of a regular Bardeen black hole in Anti-de Sitter spacetime can mimic the rotation parameter of the Kerr metric up to the value a≈0.9 providing the same innermost stable circular orbit (ISCO) radius. We have also explored the dynamics of magnetized particles with a magnetic dipole moment around a magnetically charged regular Bardeen black hole in Anti-de Sitter spacetime. As a realistic astrophysical scenario of the study, we have treated neutron stars orbiting a supermassive black hole (SMBH), in particular, the magnetar PSR J1745-2900 orbiting Sgr A* with the parameter β=10.2, as magnetized test particles. The magnetized particles dynamics shows that the parameter β, negative values of cosmological constant and magnetic charge parameter of the central BH cause a decrease in the ISCO radius. We have compared the effects of the magnetic charge of the Bardeen BH with the spin of rotating Kerr BH and shown that magnetic charge parameter can mimic the spin in the range a/M≃(0,0.7896) when Λ=0 at the range of its values g/M≃(0,0.648).

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