BTZ black hole from Poisson-Lie T-dualizable sigma models with spectators

The non-Abelian T-dualization of the BTZ black hole is discussed in detail by using the Poisson-Lie T-duality in the presence of spectators. We explicitly construct a dual pair of sigma models related by Poisson-Lie symmetry. The original model is built on a $2+1$-dimensional manifold ${\cal M} \approx O \times \bf G$, where $\bf G$ as a two-dimensional real non-Abelian Lie group acts freely on ${\cal M}$, while $O$ is the orbit of $\bf G$ in ${\cal M}$. The findings of our study show that the original model indeed is canonically equivalent to the $SL(2,\mathbb{R})$ Wess-Zumino-Witten (WZW) model for a given value of the background parameters. Moreover, by a convenient coordinate transformation we show that this model describes a string propagating in a spacetime with the BTZ black hole metric in such a way that a new family of the solutions to low energy string theory with the BTZ black hole vacuum metric, constant dilaton field and a new torsion potential is found. The dual model is built on a $2+1$-dimensional target manifold $\tilde {\cal M}$ with two-dimensional real Abelian Lie group ${\tilde {\bf G}}$ acting freely on it. We further show that the dual model yields a three-dimensional charged black string for which the mass $M$ and axion charge $Q$ per unit length are calculated. After that, the structure and asymptotic nature of the dual space-time including the horizon and singularity are determined.Comment: 20 page

Nonequilibrium quantum fluctuations of a dispersive medium: Spontaneous emission, photon statistics, entropy generation, and stochastic motion

We study the implications of quantum fluctuations of a dispersive medium, under steady rotation, either in or out of thermal equilibrium with its environment. A rotating object exhibits a quantum instability by dissipating its mechanical motion via spontaneous emission of photons, as well as internal heat generation. Universal relations are derived for the radiated energy and angular momentum as trace formulas involving the object's scattering matrix. We also compute the quantum noise by deriving the full statistics of the radiated photons out of thermal and/or dynamic equilibrium. The (entanglement) entropy generation is quantified, and the total entropy is shown to be always increasing. Furthermore, we derive a Fokker-Planck equation governing the stochastic angular motion resulting from the fluctuating back-reaction frictional torque. As a result, we find a quantum limit on the uncertainty of the object's angular velocity in steady rotation. Finally, we show in some detail that a rotating object drags nearby objects, making them spin parallel to its axis of rotation. A scalar toy model is introduced in the first part to simplify the technicalities and ease the conceptual complexities; a detailed discussion of quantum electrodynamics is presented in the second part

Spectroscopic Probe of the van der Waals Interaction between Polar Molecules and a Curved Surface

We study the shift of rotational levels of a diatomic polar molecule due to its van der Waals (vdW) interaction with a gently curved dielectric surface at temperature $T$, and submicron separations. The molecule is assumed to be in its electronic and vibrational ground state, and the rotational degrees are described by a rigid rotor model. We show that under these conditions retardation effects and surface dispersion can be neglected. The level shifts are found to be independent of $T$, and given by the quantum state averaged classical electrostatic interaction of the dipole with its image on the surface. We use a derivative expansion for the static Green's function to express the shifts in terms of surface curvature. We argue that the curvature induced line splitting is experimentally observable, and not obscured by natural line widths and thermal broadening.Comment: 8 pages, 2 figures, version accepted for publication in Phys. Rev.

Electromagnetic Casimir Forces of Parabolic Cylinder and Knife-Edge Geometries

An exact calculation of electromagnetic scattering from a perfectly conducting parabolic cylinder is employed to compute Casimir forces in several configurations. These include interactions between a parabolic cylinder and a plane, two parabolic cylinders, and a parabolic cylinder and an ordinary cylinder. To elucidate the effect of boundaries, special attention is focused on the "knife-edge" limit in which the parabolic cylinder becomes a half-plane. Geometrical effects are illustrated by considering arbitrary rotations of a parabolic cylinder around its focal axis, and arbitrary translations perpendicular to this axis. A quite different geometrical arrangement is explored for the case of an ordinary cylinder placed in the interior of a parabolic cylinder. All of these results extend simply to nonzero temperatures.Comment: 17 pages, 10 figures, uses RevTeX

Constraints on stable equilibria with fluctuation-induced forces

We examine whether fluctuation-induced forces can lead to stable levitation. First, we analyze a collection of classical objects at finite temperature that contain fixed and mobile charges, and show that any arrangement in space is unstable to small perturbations in position. This extends Earnshaw's theorem for electrostatics by including thermal fluctuations of internal charges. Quantum fluctuations of the electromagnetic field are responsible for Casimir/van der Waals interactions. Neglecting permeabilities, we find that any equilibrium position of items subject to such forces is also unstable if the permittivities of all objects are higher or lower than that of the enveloping medium; the former being the generic case for ordinary materials in vacuum.Comment: 4 pages, 1 figur

Introduction

This volume of the Economic Policy Review, "Special issue on the economic effects of September 11," explores some of the key economic consequences of the attacks of September 11. The six articles that make up the volume address several important questions: how great were the losses in New York City on September 11 and in the difficult months thereafter? How much will the nation spend to prevent future attacks? Did the destruction of information and infrastructure impair the functioning of the payments and securities settlement systems, and what steps minimize further damage? Will these events hurt New York's future vitality and cause businesses and workers to retreat from the city? ; The six articles fall into three broad groups: 1) detailed accountings of economic costs--those incurred as a direct consequence of the September 11 attacks and those arising from efforts to prevent future attacks, 2) studies of the attacks' disruptive effects on the payments and securities settlement systems, and 3) analyses of New York City's prospects after September 11.Disaster relief ; Terrorism ; War - Economic aspects ; Economic conditions - New York (N.Y.) ; Federal Reserve District, 2nd

An Effective Membrane Model of the Immunological Synapse

The immunological synapse is a patterned collection of different types of receptors and ligands that forms in the intercellular junction between T Cells and antigen presenting cells (APCs) during recognition. The synapse is implicated in information transfer between cells, and is characterized by different spatial patterns of receptors at different stages in the life cycle of T cells. We obtain a minimalist model that captures this experimentally observed phenomenology. A functional RG analysis provides further insights.Comment: 6 pages, 3 figures, submitted for publicatio

TRA-962: COLOURED ASPHALT BUS RAPID TRANSIT LANES IN THE REGIONAL MUNICIPALITY OF YORK: INTEGRATING LABORATORY PERFORMANCE TESTING INTO SUSTAINABLE PAVEMENT ASSET MANAGEMENT

Located north of Toronto, Ontario, The Regional Municipality of York, the sixth largest municipality in Canada, is a thriving community and home to a well-established service sector. York Region’s population is expected to grow from 1.1 million in 2013 to 1.8 million in 2041. With more people coming to the Region every year, Rapid Transit projects provide significant benefits. Bus Rapid Transit (BRT) lanes are built or being built along the three most heavily travelled roads in York Region: Yonge Street, Highway 7 and Davis Drive. To improve the level of safety through enhanced visibility and help residents and motorists easily understand this new transit system and follow the right-of-way, York Region uses coloured asphalt pavement design for its dedicated BRT lanes. York Region and Metrolinx, an agency of the Government of Ontario created to improve the coordination and integration of all modes of transportation in the Greater Toronto and Hamilton Area, retained the Centre for Pavement and Transportation Technology (CPATT), located at the University of Waterloo, to identify innovative and sustainable future preservation and maintenance solutions to ensure durability and high performance throughout the material’s life cycle. This paper highlights information on how coloured asphalt can be used to achieve technical and social benefits in a number of transportation applications. This paper also looks at pavement performance results obtained from conducting material testing at the state-of-the-art pavement laboratory at CPATT. These results provide insight into the level of resistance the pavement structure will exhibit to loss of surficial colour and friction due to inevitable wear and tear. These results are used to compliment performance prediction models describing the expected path of deterioration over time. Materials under evaluation included those collected during paving operations and those produced under controlled laboratory conditions

Modulation of P-glycoprotein activity in Calu-3 cells using steroids and β-ligands

Please note that this is an author-produced PDF of an article accepted for publication following peer review. The publisher version is available on its site.The purpose of this work was to investigate if P-glycoprotein (Pgp) efflux pump activity could be inhibited in the sub-bronchial epithelial cell line, Calu-3, by glucocorticosteroids and β-ligands. The Pgp modulation efficiency of each compound was determined by its ability to increase the accumulation of the Pgp substrate rhodamine 123 (Rh123) accumulation in these cells. Pgp inhibition was observed at ≥ 100 μM steroids and β-ligand. The modulation effectiveness of the β-ligands increased with increasing hydrophobicity (log Poctanol/aqueous) whereas an obvious correlation was not obtained with the complete set of steroids tested. Steroidal Pgp substrates did not affect Rh123 accumulation (e.g., aldosterone, dexamethasone, 11β, 17α, 21-OH progesterone). In contrast, two hydrophobic non P-gp steroidal substrates (testosterone and progesterone) displayed different effects on Rh123 accumulation, with progesterone being the more potent modulator. The most hydrophobic β-ligand, propranolol, a known Pgp substrate, gave the largest increase in Rh123 accumulation in this therapeutic class. The β-ligand modulation efficiency could also be correlated to Pgp structural recognition elements such as hydrogen bonding potential, the presence of a basic nitrogen and planar aromatic ring. No effect on Rh123 accumulation was observed with the formulation additives tested (ethanol, glycerol and palmitoyl carnitine) at concentrations previously reported to be non-toxic to Calu-3 cells

The Unusual Universality of Branching Interfaces in Random Media

We study the criticality of a Potts interface by introducing a {\it froth} model which, unlike its SOS Ising counterpart, incorporates bubbles of different phases. The interface is fractal at the phase transition of a pure system. However, a position space approximation suggests that the probability of loop formation vanishes marginally at a transition dominated by {\it strong random bond disorder}. This implies a linear critical interface, and provides a mechanism for the conjectured equivalence of critical random Potts and Ising models.Comment: REVTEX, 13 pages, 3 Postscript figures appended using uufile