1,110 research outputs found
Higher Dimensional Choptuik Scaling in Painleve Gullstrand Coordinates
We investigate Choptuik scaling in the spherically symmetric collapse of a
massless scalar field in higher dimensions using Painleve-Gullstrand (P-G)
coordinates. Our analysis confirms the presence in higher dimensions of the
cusps in the periodic scaling relationship recently observed in four
dimensional collapse. In addition, we address the issue of the asymptotic
behaviour of the critical exponent as the number of spacetime dimensions gets
large. Our results are consistent with earlier work suggesting that the
critical exponent monotonically approaches 1/2 in this limit.Comment: 11 pages, 5 figure
Hamiltonian dynamics of Lovelock black holes with spherical symmetry
We consider spherically symmetric black holes in generic Lovelock gravity.
Using geometrodynamical variables we do a complete Hamiltonian analysis,
including derivation of the super-Hamiltonian and super-momentum constraints
and verification of suitable boundary conditions for asymptotically flat black
holes. Our analysis leads to a remarkably simple fully reduced Hamiltonian for
the vacuum gravitational sector that provides the starting point for the
quantization of Lovelock block holes. Finally, we derive the completely reduced
equations of motion for the collapse of a spherically symmetric charged,
self-gravitating complex scalar field in generalized flat slice
(Painlev\'{e}-Gullstrand) coordinates.Comment: 53 pages, including two major appendices; some typos fixed; version
published in CQ
Quantum Mechanics of the Interior of Radiating 2-D Black Holes
We study the homogeneous sector of the RST model describing the gravitational
dynamics, including back-reaction, of radiating 2-d black holes. We find the
exact solutions both in conformal gauge and in time-parametrized form, isolate
the black hole sector of the classical phase space and quantize the near
singularity dynamics in conformal gauge. We show that different choices of
measure and different self-adjoint extensions can lead to inequivalent quantum
theories, all of which resolve the singularity. For a specific range of
extension parameters, the Hamiltonian spectrum admits bound states that
correspond physically to stable remnants. Finally, we argue that our work
provides a good starting point for quantization of the full homogeneous theory
using both reduced and Dirac quantization
Integrability of the Einstein-nonlinear -model in a nontrivial topological sector
The integrability of the\ Einstein-nonlinear -model
with nonvanishing cosmological charge is studied. We apply the method of
singularity analysis of differential equations and we show that the equations
for the gravitational field are integrable. The first few terms of the solution
are presented.Comment: 6 pages, 2 figures, published at EPJ
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Bradley King
During the preliminary research that culminated in my volume Talbot Mundy, Philosopher of Adventure (McFarland 2005), I investigated the anomaly of the book Her Reputation, titled The Bubble Reputation in the UK, Mundy’s sole literary collaboration as well as the only book he wrote with a “photoplay edition” motion picture tie-in. Who was his coauthor, Bradley King? The standard references offered only a long list of credits. The Academy of Motion Picture Arts & Sciences had two clippings, revealing that “Bradley” was not a man, but an attractive female brunette. County and city legal records were the next recourse, and other bits came from brief mentions in articles and papers, found as I began researching a biography of producer Thomas Ince (1880–1924). From this research I realized that, despite King’s obscurity today, she ranked as one of the leading female screenwriters during the 1920s and 1930s
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