135,587 research outputs found
Liouville Black Holes
The dynamics of Liouville fields coupled to gravity are investigated by
applying the principle of general covariance to the Liouville action in the
context of a particular form of two-dimensional dilaton gravity. The resultant
field equations form a closed system for the Liouville/gravity interaction. A
large class of asymptotically flat solutions to the field equations is
obtained, many of which can be interpreted as black hole solutions. The
temperature of such black holes is proportional to their mass-parameters. An
exact solution to the back reaction problem is obtained to one-loop order, both
for conformally coupled matter fields and for the quantized metric/Liouville
system. Quantum effects are shown to map the space of classical solutions into
one another. A scenario for the end-point of black-hole radiation is discussed.Comment: 32 pgs., WATPHYS-TH93/03 (Latex plus two postscript figures appended
Families of exact solutions of a 2D gravity model minimally coupled to electrodynamics
Three families of exact solutions for 2-dimensional gravity minimally coupled
to electrodynamics are obtained in the context of theory. It is
shown, by supersymmetric formalism of quantum mechanics, that the quantum
dynamics of a neutral bosonic particle on static backgrounds with both varying
curvature and electric field is exactly solvable.Comment: 13 pages, LaTeX, to be published in JM
Statistical Mechanics of Relativistic One-Dimensional Self-Gravitating Systems
We consider the statistical mechanics of a general relativistic
one-dimensional self-gravitating system. The system consists of -particles
coupled to lineal gravity and can be considered as a model of
relativistically interacting sheets of uniform mass. The partition function and
one-particle distitrubion functions are computed to leading order in
where is the speed of light; as results for the
non-relativistic one-dimensional self-gravitating system are recovered. We find
that relativistic effects generally cause both position and momentum
distribution functions to become more sharply peaked, and that the temperature
of a relativistic gas is smaller than its non-relativistic counterpart at the
same fixed energy. We consider the large-N limit of our results and compare
this to the non-relativistic case.Comment: latex, 60 pages, 22 figure
SUSY Searches for Inclusive Squark and Gluino Production at the LHC
A selection of recent searches for Supersymmetry conducted by the ATLAS and
CMS collaborations is presented, summarizing the relevant results for inclusive
squark and gluino production at the LHC. No indication for the existence of
Supersymmetry in terms of an excess above the Standard Model background is seen
by any analysis, therefore limits are reported on parameters of the various
models used to interpret the findings.Comment: 4 pages, 4 figures, submitted to the Proceedings of the 48th
Rencontres de Moriond on QCD and High Energy Interactions, La Thuile, Italy,
9 - 16 Mar 201
Family Coverage: Covering Parents Along With Their Children
Explores the high uninsured rate among parents compared to children, due to the lack of both employer-sponsored and public insurance options. Argues for expanding state Medicaid coverage to parents. Offers strategies for addressing costs and other issues
Supergravity from a Massive Superparticle and the Simplest Super Black Hole
We describe in superspace a theory of a massive superparticle coupled to a
version of two dimensional N=1 dilaton supergravity. The (1+1) dimensional
supergravity is generated by the stress-energy of the superparticle, and the
evolution of the superparticle is reciprocally influenced by the supergravity.
We obtain exact superspace solutions for both the superparticle worldline and
the supergravity fields. We use the resultant non-trivial compensator
superfield solution to construct a model of a two-dimensional supersymmetric
black hole.Comment: Latex, 27 pages, minor typos corrected and reference adde
Towards sharing in lazy computation systems
Work on proving congruence of bisimulation in functional programming languages often refers to [How89,How96], where Howe gave a highly general account on this topic in terms of so-called lazy computation systems . Particularly in implementations of lazy functional languages, sharing plays an eminent role. In this paper we will show how the original work of Howe can be extended to cope with sharing. Moreover, we will demonstrate the application of our approach to the call-by-need lambda-calculus lambda-ND which provides an erratic non-deterministic operator pick and a non-recursive let. A definition of a bisimulation is given, which has to be based on a further calculus named lambda-~, since the na1ve bisimulation definition is useless. The main result is that this bisimulation is a congruence and contained in the contextual equivalence. This might be a step towards defining useful bisimulation relations and proving them to be congruences in calculi that extend the lambda-ND-calculus
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