6,724 research outputs found
Two-Dimensional Quantum Geometry
In these lectures we review our present understanding of the fractal
structure of two-dimensional Euclidean quantum gravity coupled to matter.Comment: Lectures presented at "The 53rd Cracow School of Theoretical Physics:
Conformal Symmetry and Perspectives in Quantum and Mathematical Gravity",
June 28 - July 7, 2013, Zakopane, Polan
The effective kinetic term in CDT
We report on recently performed simulations of Causal Dynamical
Triangulations (CDT) in 2+1 dimensions aimed at studying its effective dynamics
in the continuum limit. Two pieces of evidence from completely different
measurements are presented suggesting that three-dimensional CDT is effectively
described by an action with kinetic term given by a modified Wheeler-De Witt
metric. These observations could strengthen an earlier observed connection
between CDT and Horava-Lifshitz gravity. One piece of evidence comes from
measurements of the modular parameter in CDT simulations with spatial topology
of a torus, the other from measurements of local metric fluctuations close to a
fixed spatial boundary.Comment: 4 pages, 4 figures, based on a talk given at Loops '11, Madrid, to
appear in Journal of Physics: Conference Series (JPCS
Generalized multicritical one-matrix models
We show that there exists a simple generalization of Kazakov's multicritical
one-matrix model, which interpolates between the various multicritical points
of the model. The associated multicritical potential takes the form of a power
series with a heavy tail, leading to a cut of the potential and its derivative
at the real axis, and reduces to a polynomial at Kazakov's multicritical
points. From the combinatorial point of view the generalized model allows
polygons of arbitrary large degrees (or vertices of arbitrary large degree,
when considering the dual graphs), and it is the weight assigned to these large
order polygons which brings about the interpolation between the multicritical
points in the one-matrix model.Comment: 25 page
Scale-dependent Hausdorff dimensions in 2d gravity
By appropriate scaling of coupling constants a one-parameter family of
ensembles of two-dimensional geometries is obtained, which interpolates between
the ensembles of (generalized) causal dynamical triangulations and ordinary
dynamical triangulations. We study the fractal properties of the associated
continuum geometries and identify both global and local Hausdorff dimensions.Comment: 12 pages, 3 figure
Modeling Neutrino Quasielastic Cross Sections on Nucleons and Nuclei
We calculate the total and differential quasielastic cross sections for
neutrino and antineutrino scattering on nucleons using up to date fits to the
nucleon elastic electromagnetic form factors , , ,
, and and pseudoscalar form factors. We compare predictions of the
cross sections for nucelons and nuclei to experimental data.Comment: 5 pages, 4 figures, Presented by Arie Bodek at CIPANP2003, New York
City, NY 2003 - to be published in proceeding
Oblique-incidence secondary emission from charged dielectrics
Secondary electron emission coefficients were measured on FEP-Teflon for normal and oblique incidence in the presence of a normal electric field. Such measurements require knowledge of the electrostatic environment surrounding the specimen, and they require calculation of particle trajectories such that particle impact parameters can be known. A simulation using a conformal mapping, a Green's integral, and a trajectory generator provides the necessary mathematical support for the measurements, which were made with normal fields of 1.5 and 2.7 kV/mm. When incidence is normal and energy exceeds the critical energy, the coefficient is given by (V sub 0/V) to the .58 power, and for oblique incidence this expression may be divided by the cosine of the angle. The parameter V sub 0 is a function of normal field
Balancing Efficiency, Equity, and Voice in Workplace Resolution Procedures
Systems for resolving workplace disputes are very important to workers and firms, and have been the subject of much debate. In the United States, traditional unionized grievance procedures, emerging nonunion dispute resolution systems, and the court-based system for resolving employment law disputes have all been criticized. Much of the existing debate on workplace dispute resolution, however, has been atheoretical, with a focus on techniques of dispute resolution rather than the goals of the system. What is missing from the debate are fundamental standards for comparing and evaluating dispute resolutions systems. In this paper, we develop efficiency, equity, and voice as these standards. Unionized, nonunion, and employment law procedures are then evaluated against these three standards.
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