Results 11 to 20 of about 35,096 (197)
Penrose limits and spacetime singularities [PDF]
Classical and Quantum Gravity, 2004 We give a covariant characterisation of the Penrose plane wave limit: the plane wave profile matrix $A(u)$ is the restriction of the null geodesic deviation matrix (curvature tensor) of the original spacetime metric to the null geodesic, evaluated in a comoving frame.
Blau, M +3 more
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SPACETIME SINGULARITIES: RECENT DEVELOPMENTS [PDF]
International Journal of Modern Physics D, 2013 Recent developments concerning oscillatory spacelike singularities in general relativity are taking place on two fronts. The first treats generic singularities in spatially homogeneous cosmology, most notably Bianchi types VIII and IX. The second deals with generic oscillatory singularities in inhomogeneous cosmologies, especially those with two ...
Claes Uggla
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On the genericity of spacetime singularities [PDF]
Pramana - Journal of Physics, 2007 We consider here the genericity aspects of spacetime singularities that occur in cosmology and in gravitational collapse. The singularity theorems (that predict the occurrence of singularities in general relativity) allow the singularities of ...
A. K. Raychaudhuri +21 more
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Living Reviews in Relativity, 2008 Quantum gravity is expected to be necessary in order to understand situations in which classical general relativity breaks down. In particular in cosmology one has to deal with initial singularities, i.e., the fact that the backward evolution of a ...
Bojowald Martin
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A singular conformal spacetime [PDF]
Journal of Geometry and Physics, 2006 The infinite cosmological "constant" limit of the de Sitter solutions to Einstein's equation is studied. The corresponding spacetime is a singular, four-dimensional cone-space, transitive under proper conformal transformations, which constitutes a new example of maximally-symmetric spacetime. Grounded on its geometric and thermodynamic properties, some
Aldrovandi, R. +2 more
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QUANTUM SINGULARITIES IN STATIC SPACETIMES [PDF]
International Journal of Modern Physics D, 2011 We review the mathematical framework necessary to understand the physical content of quantum singularities in static spacetimes. We present many examples of classical singular spacetimes and study their singularities by using wave packets satisfying Klein–Gordon and Dirac equations.
Pitelli, João Paulo M. +1 more
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Dynamic generation or removal of a scalar hair
Journal of High Energy Physics, 2023 We study dynamic processes through which the scalar hair of black holes is generated or detached in a theory with a scalar field non-minimally coupled to Gauss-Bonnet and Ricci scalar invariants.
Yunqi Liu +4 more
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Regular black holes without mass inflation instability
Journal of High Energy Physics, 2022 Generic models of regular black holes have separate outer and inner horizons, both with nonzero surface gravity. It has been shown that a nonzero inner horizon surface gravity results in exponential instability at the inner horizon controlled by this ...
Raúl Carballo-Rubio +4 more
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Journal of High Energy Physics, 2023 The verification of the second law of black hole mechanics and the WCCC in the context of enthalpy as mass of the black hole and its related thermodynamic properties has not been tested through a vast number of literature in the recent past. Such studies
Md Sabir Ali +3 more
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Journal of High Energy Physics, 2022 In this work, we consider a very simple gravitational theory that contains a scalar field with its kinetic and potential terms minimally coupled to gravity, while the scalar field is assumed to have a coulombic form.
Athanasios Bakopoulos, Theodoros Nakas
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