December 2001 arXiv papers — page 13

G. Gaeta

We briefly review the main aspects of (Poincaré-Dulac) normal forms; we have a look at the non-uniqueness problem, and discuss one of the proposed ways to ``further reduce'' the normal forms. We also mention some convergence results.

Jinho Baik, Percy Deift, Ken McLaughlin, Peter Miller

In this paper, we obtain optimal uniform lower tail estimates for the probability distribution of the properly scaled length of the longest up/right path of the last passage site percolation model considered by Johansson in [12]. The estimates are used to prove a lower tail moderate deviation result for the model. The estimates also imply the convergence of

Luis Álvarez-Cónsul, Oscar García-Prada

In this paper we study gauge theory on SL(2,C)-equivariant bundles over XxP^1, where X is a compact Kahler manifold, P^1 is the complex projective line, and the action of SL(2,C) is trivial on X and standard on P^1. We first classify these bundles, showing that they are in correspondence with objects on X - that we call holomorphic chains - consisting of a f

Donald Marolf

The fact that both the D6-brane and the orientifold 6-plane have smooth, horizon-free descriptions in M-theory makes them especially useful in understanding certain aspects of brane physics. We briefly review how this connection has been used to understand a number of effects, several of which are associated with the Hanany-Witten transition. One particular

A. J. M. Medved

Some recent literature has examined the holographic-induced cosmology of a brane universe in the background of an anti-de Sitter-black hole geometry. In this regard, curved-brane scenarios have begun to receive considerable attention. Our current interest is in a formal discrepancy that exists between two such works by Padilla (hep-th/0111247) and Youm (hep-

J. Olsson

Several topics from the wide field of QCD studies in Deep-inelastic $ep$ Scattering at HERA are addressed. They include QCD analyses of the inclusive cross section with the determination of $α_s$ and the proton gluon density from the $F_2$ scaling violations, and the determination of the longitudinal structure function $F_L$. QCD analyses of inclusive jet an

Akos Csilling

Recent improvements in the analysis techniques and Monte Carlo models used in the measurement of the hadronic structure function of the photon have lead to much improved experimental results. Its low x behaviour was studied in various Q^2 regions using LEP1 and LEP2 data, while its x dependence and Q^2 evolution up to very high virtualities, as well as its c

Donald Marolf

The talks presented in the string theory and supergravity session of the GR16 conference in Durban, South Africa are described below for the proceedings.

Sanjay M. Wagh, Keshlan S. Govinder

Self-similar spacetimes are of importance to cosmology and to gravitational collapse problems. We show that self-similarity or the existence of a homothetic Killing vector field for spherically symmetric spacetimes implies the separability of the spacetime metric in terms of the co-moving coordinates and that the metric is, uniquely, the one recently reporte

S. M. Wagh, R. V. Saraykar, P. S. Muktibodh, K. S. Govinder

In this paper, we investigate the nature of the singularity in the spherically symmetrical, shear-free, gravitational collapse of a star with heat flux using a separable metric [cqg1]. For any non-singular, regular, radial density profile for a star described by this metric, eq. (2.1), the singularity of the gravitational collapse is not naked locally. Our r

S. M. Wagh, R. V. Saraykar, P. S. Muktibodh, K. S. Govinder

In this paper, we find all the Conformal Killing Vectors (CKVs) and their Lie Algebra for the recently reported [cqg1] spherically symmetric, shear-free separable metric spacetimes with non-vanishing energy or heat flux. We also solve the geodesic equatios of motion for the spacetime under consideration.

Patrik Recher, Daniel Loss

We consider an s-wave superconductor (SC) which is tunnel-coupled to two spatially separated Luttinger liquid (LL) leads. We demonstrate that such a setup acts as an entangler, i.e. it creates spin-singlets of two electrons which are spatially separated, thereby providing a source of electronic Einstein-Podolsky-Rosen pairs. We show that in the presence of a

G. J. Szabo, M. J. Alava, J. Kertesz

Kardar-Parisi-Zhang interface depinning with quenched noise is studied in an ensemble that leads to self-organized criticality in the quenched Edwards-Wilkinson (QEW) universality class and related sandpile models. An interface is pinned at the boundaries, and a slowly increasing external drive is added to compensate for the pinning. The ensuing interface be

P. Sebbah, B. Hu, A. Z. Genack, R. Pnini

The absence of self averaging in mesoscopic systems is a consequence of long-range intensity correlation. Microwave measurements suggest and diagrammatic calculations confirm that the correlation function of the normalized intensity with displacement of the source and detector, $ΔR$ and $Δr$, respectively, can be expressed as the sum of three terms, with dis

Franco Ferrari

In [1] a new bosonization procedure has been illustrated, which allows to express a fermionic gaussian system in terms of commuting variables at the price of introducing an extra dimension. The Fermi-Bose duality principle established in this way has many potential applications also outside the context of gauge field theories in which it has been developed.

Yu. Kagan, L. A. Maksimov

We discuss an existence of the damping for the radial condensate oscillations in a cylindric trap at zero temperature. The damping is a result of the parametric resonance leading to energy transfer from the coherent condensate oscillations to the longitudinal sound waves within a finite frequency interval. The parametric resonance is due to the oscillations

A. Koitzsch, G. Blumberg, A. Gozar, B. Dennis

For CaCu$_{3}$Ti$_{4}$O$_{12}$ -- an insulator that exhibits a giant dielectric response above 100 K -- Cu$^{2+}$ antiferromagnetic spin ordering has been investigated by magnetic Raman scattering and magnetization measurements. Below the Néel temperature, T$_{N} = 25$ K, magnetic excitations have been identified. Above T$_{N}$ Raman spectra reveal short-ran

Dibyendu Das, Jane' Kondev, Bulbul Chakraborty

We propose a new scenario for glassy dynamics in frustrated systems with no quenched-in randomness, based on jamming of extended dynamical structures near a critical point. This route to a glassy state is demonstrated in a lattice model of fluctuating lines. Numerical simulations of the model show non-exponential relaxations and diverging energy barriers in

V. S. Babichenko

An effective action is obtained of a Bose gas in the bulk separated into two regions by a strong external potential depending on the single coordinate. The main attention is focused on the relaxation of the difference between phases of the weakly coupling condensates of the different bulk domains separated from each other by the external potential.

Luigi Foschini

This letter presents a new solution for the Tunguska event of June 30th, 1908. The solution has been obtained starting from seismic data, is in fair agreement with the observational evidence, and supports the asteroidal hypothesis for the origin of the Tunguska cosmic body. It is based on an improved model of the hypersonic flow around a small asteroid in th

Luigi Foschini

On January 19, 1993, a very bright bolide (peak magnitude -23) crossed the sky of Northern Italy, ending with an explosion approximately over the town of Lugo (Emilia Romagna, Italy). The explosion (14 kton of energy) generated shock waves which were recorded by six local seismic stations. A reanalysis of the available data leads us to the hypothesis that th

Luigi Foschini

In this paper, a meteoric plasma is analyzed from a physical viewpoint, with particular emphasis on its interaction with radio waves. The attention is drawn to some macroscopic characteristics of a meteoric plasma and it is shown that the electron-ion collision frequency is not negligible, as commonly thought.

T. A. Lozinskaya, V. P. Arkhipova, A. V. Moiseev, V. L. Afanasiev

The single region of ongoing star formation in the galaxy IC 1613 has been observed in order to reveal the nature of compact emission-line objects at the edges of two shells in the complex, identified earlier in H-alpha line images. The continuum images show these compact objects to be stars. Detailed spectroscopic observations of these stars and the surroun

M. Beech, L. Foschini

The sounds accompanying electrophonic burster meteors are characteristically described as being akin to short duration ``pops'' and staccato--like ``clicks''. As a phenomenon distinct from the enduring electrophonic sounds that occasionally accompany the passage and ablation of large meteoroids in the Earth's lower atmosphere, the burster

A. Carbognani, M. De Meyere, L. Foschini, C. Steyaert

It is known from theory that, by means of a plasma physics approach, it is possible to obtain a simple formula to calculate the approximate height of a meteor (Foschini, 1999). This formula can be used in case of forward scatter of radio waves and has the advantage that it does not depend on the diffusion coefficient. On the other hand, it is possible to app

Hajime Baba, Kozo Sadakane, Yuji Norimoto, Kazuya Ayani

Intermediate resolution phase-resolved spectra of WZ Sge were obtained on five consecutive nights (July 23 -- 27) covering the initial stage of the 2001 superoutburst. Double-peaked emission lines of He\textsc{II} at 4686 Å, which were absent on July 23, emerged on July 24 together with emission lines of C\textsc{III} / N\textsc{III} Bowen blend. Analyses of

Taichi Kato

We examined the VSNET light curve of the ER UMa-type star V1159 Ori. We detected a large variation of the supercycle (the interval between successive superoutbursts) between extremes of 44.6 and 53.3 d. The outburst activity was also found to decrease when the supercycle was long. The observed variation of the supercycle corresponds to a variation of ~40 % o

I. Kravchenko

The RICE experiment (Radio Ice Cherenkov Experiment) at the South Pole, co-deployed with the AMANDA experiment, seeks to detect ultra-high energy (UHE) electron neutrinos interacting in cold polar ice. Such interactions produce electromagnetic showers, which emit radio-frequency Cherenkov radiation. We describe the experimental apparatus and the procedures u

Michel Sorel, Janet Conrad

The observation of the $\barν_e$ energy spectrum from a supernova burst can provide constraints on neutrino oscillations. We derive formulas for adiabatic oscillations of supernova antineutrinos for a variety of 3- and 4-neutrino mixing schemes and mass hierarchies which are consistent with the LSND evidence for $\barν_μ\to \barν_e$ oscillations. Finally, we

Herve M. Carruzzo, Clare C. Yu

We introduce a new quantity to probe the glass transition. This quantity is a linear generalized compressibility which depends solely on the positions of the particles. We have performed a molecular dynamics simulation on a glass forming liquid consisting of a two component mixture of soft spheres in three dimensions. As the temperature is lowered (or as the

M. F. M. Lutz, Gy. Wolf, B. Friman

We construct a relativistic and unitary approach to 'high' energy pion- and photon-nucleon reactions taking the $πN, πΔ$, $ρN$, $ωN$, $ηN, K Λ, K Σ$ final states into account. Our scheme dynamically generates the s- and d-wave nucleon resonances N(1535), N(1650) and N(1520) and isobar resonances $Δ(1620)$ and $Δ(1700)$ in terms of quasi-local interac

B. Schnurr, F. Gittes, F. C. MacKintosh

Motivated by results from an earlier Brownian Dynamics (BD) simulation for the collapse of a single, stiff polymer in a poor solvent [B. Schnurr, F. C. MacKintosh, and D. R. M. Williams, Europhys. Lett. 51 (3), 279 (2000)] we calculate the conformational energies of the intermediate (racquet) states suggested by the simulations. In the absence of thermal flu

H. Asklund, L. Ilver, J. Kanski, J. Sadowski

Using angle-resolved photoemission, we have investigated the development of the electronic structure and the Fermi level pinnning in Ga$_{1-x}$Mn$_{x}$As with Mn concentrations in the range 1--6%. We find that the Mn-induced changes in the valence-band spectra depend strongly on the Mn concentration, suggesting that the interaction between the Mn ions is mor

Klaus Behrndt, Gianguido Dall'Agata

We discuss a class of 4-dimensional non-homogeneous quaternionic spaces, which become the two known homogeneous spaces (EAdS_4$ and SU(2,1)/U(2)) in certain limits. These moduli spaces have two regions where the metric is positive definite, separated by a non-physical region where the metric has timelike directions and which contains a curvature singularity.

A. Lazarian, Huirong Yan

Interstellar medium is turbulent and this induces relative motions of dust grains. We calculate relative velocities of charged grains in a partially ionized magnetized gas. We account for anisotropy of magnetohydrodynamic (MHD) turbulence, grain coupling with magnetic field, and the turbulence cutoff arising from the ambipolar drag. We obtain grain velocitie

Yaoyun Shi

Given a function f as an oracle, the collision problem is to find two distinct inputs i and j such that f(i)=f(j), under the promise that such inputs exist. Since the security of many fundamental cryptographic primitives depends on the hardness of finding collisions, quantum lower bounds for the collision problem would provide evidence for the existence of c

P. Braun-Munzinger, J. Stachel

We discuss the status of thermal model descriptions of particle ratios in central nucleus-nucleus collisions at ultra-relativistic energy. An alternative to the ``Cleymans-Redlich'' interpretation of the freeze-out trajectory is given in terms of the total baryon density. Emphasis is placed on the relation between the chemical equilibration parameter

G. Verde, D. A. Brown, P. Danielewicz, C. K. Gelbke

We investigate two-proton correlation functions for reactions in which fast dynamical and slow evaporative proton emission are both present. In such cases, the width of the correlation peak provides the most reliable information about the source size of the fast dynamical component. The maximum of the correlation function is sensitive to the relative yields

A. V. Roiter

We introduce a generalization of representations of quivers that contains also representations of posets, vectorspace problems and other matrix problems. Many examples, some of which are given in the paper, show that the language of marked quivers is rather convenient and that the notion of their representations can probably be considered as basic for a gene

I. Heckenberger, S. Kolb

For differential calculi over certain right coideal subalgebras of quantum groups the notion of quantum tangent space is introduced. In generalization of a result by Woronowicz a one to one correspondence between quantum tangent spaces and covariant first order differential calculi is established. This result is used to classify differential calculi over qua

Stefan Kolb

Covariant first order differential calculus over quantum complex Grassmann manifolds is considered. It is shown by a Pusz-Woronowicz type argument that under restriction to calculi close to classical Kaehler differentials there exist exactly two such calculi for the homogeneous coordinate ring. Complexification and localization procedures are used to induce

Takeshi Katsura

We investigate the structures of crossed products of the Cuntz algebra ${\mathcal O}_\infty$ by quasi-free actions of abelian groups. We completely determine their ideal structures and compute the strong Connes spectra and K-groups.

Alex Brudnyi

In the paper we prove an extension theorem for matrices with entries in H^{\infty}(U) for U being a Riemann surface of a special type. One of the main components of the proof is a Grauert type theorem for "holomorphic" vector bundles defined over maximal ideal spaces of certain Banach algebras. The proof is also based on the results of A.Brudnyi &#34

Xi Chen

Fix a very general hypersurface D in P^n of degree at least 2n + 1 and we show that the complement P^n - D does not contain any algebraic torus C^*.

Amnon Besser, Rob de Jeu

We define complexes analogous to Goncharov's complexes for the K-theory of discrete valuation rings of characteristic zero. Under suitable assumptions in K-theory, there is a map from the cohomology of those complexes to the K-theory of the ring. In case the ring is the localization of the ring of integers in a number field, there are no assumptions nece

Ron Fulp, Tom Lada, Jim Stasheff

The physics of ``particles of spin $\leq 2$'' leads to representations of a Lie algebra $Ξ$ of gauge parameters on a vector space $Φ$ of fields. Attempts to develop an analogous theory for spin $>2$ have failed; in fact, there are claims that such a theory is impossible (though we have been unable to determine the hypotheses for such a `no-go' th

Makoto Sakaguchi

We propose a pregeometrical formulation of Berkovits' open Ramond-Neveu-Schwarz (RNS) superstring field theories. We show that Berkovits' open RNS superstring field theories arise by expanding around particular solutions of the classical equations of motion for this theory. Our action contains pure ghost operators only and so is formally background i

M. Teper

I show how one can use lattice methods to calculate various continuum properties of SU(N) gauge theories; in part to explore old ideas that N=3 might be close to N=infinity. I describe calculations of the low-lying `glueball' mass spectrum, of the string tensions of k-strings and of topological fluctuations for N=2,3,4,5. We find that mass ratios appear

Aaron Roodman

The BABAR experiment at the PEP-II asymmetric B factory at SLAC has collected a large sample of data at the $Υ(4S)$ resonance. I will summarize BABAR's new results on CP violation, B mixing and lifetimes, and a selection of rare B decays. In particular, I will describe in detail the measurement of the CP violating parameter $\sin{2β}$; BABAR has observed

Finn Ravndal, Mats Sundberg

The differential cross-sections for scattering of gravitons into photons on bosons and fermions are calculated in linearized quantum gravity. They are found to be strongly peaked in the forward direction and become constant at high energies. Numerically, they are very small as expected for such gravitational interactions.

Marcus Hutter

The mutual information of two random variables i and j with joint probabilities t_ij is commonly used in learning Bayesian nets as well as in many other fields. The chances t_ij are usually estimated by the empirical sampling frequency n_ij/n leading to a point estimate I(n_ij/n) for the mutual information. To answer questions like "is I(n_ij/n) consiste

Lillian Lee

In 1975, Valiant showed that Boolean matrix multiplication can be used for parsing context-free grammars (CFGs), yielding the asympotically fastest (although not practical) CFG parsing algorithm known. We prove a dual result: any CFG parser with time complexity $O(g n^{3 - \epsilson})$, where $g$ is the size of the grammar and $n$ is the length of the input

R. B. Pandey, D. Stauffer, R. Seyfarth, Luis A. Cueva

A computer simulation model is used to study the density profile and flow of a miscible gaseous fluid mixture consisting of differing constituent masses ($m_A = m_B/3$) through an open matrix. The density profile is found to decay with the height $\propto \exp(-m_{A(B)}h)$, consistent with the barometric height law. The flux density shows a power-law increas

A. M. Dyugaev, I. D. Vagner, P. Wyder

We present a theoretical study of the influence of the nuclear ferromagnetism on superconductivity in the presence of the electron-nuclear spin interaction. It is demonstrated that in some metals, e.g. Rh, W, the BCS condensate imbedded in a matrix of ferromagneticaly ordered nuclear spins should manifest the FFLO (Fulde-Ferel-Larkin-Ovchinniov) state. We ou

M. Richterova, V. Lisy

The Kerr effect on vesicle-like droplets is described. We give a simple derivation of the Kerr constant for a dielectric fluid droplet immersed in another fluid, assuming that the droplet in an electric field becomes a prolate ellipsoid. The Kerr constant is evaluated also for a droplet covered by a membrane of finite thickness. The latter result differs sig

A. Badía, C. López

Critical state problems which incorporate more than one component for the magnetization vector of hard superconductors are investigated. The theory is based on the minimization of a cost functional ${\cal C}[\vec{H}(\vec{x})]$ which weighs the changes of the magnetic field vector within the sample. We show that Bean's simplest prescription of choosing th

S. J. J. M. F. Kokkelmans, J. N. Milstein, M. L. Chiofalo, R. Walser

We derive a theory of superfluidity for a dilute Fermi gas that is valid when scattering resonances are present. The treatment of a resonance in many-body atomic physics requires a novel mean-field approach starting from an unconventional microscopic Hamiltonian. The mean-field equations incorporate the microscopic scattering physics, and the solutions to th

Alessandro De Angelis

The new generation of astroparticle experiments will use technologies common to High Energy Physics. Among such technologies a central place is given to the role of simulation.

Christian Marinoni, Marc Davis, Jeffrey A. Newman, Alison L. Coil

We have developed a new geometrical method for identifying and reconstructing a homogeneous and highly complete set of galaxy groups in the next generation of deep, flux-limited redshift surveys. Our method combines information from the three-dimensional Voronoi diagram and its dual, the Delaunay triangulation, to obtain group and cluster catalogs that are r

Christian Marinoni, Michael J. Hudson, Giuliano Giuricin

We derive the observed luminosity function of virialized systems. Coupling this statistic with the mass function predicted by CDM cosmogonies we obtain the functional behavior of the mass-to-light ratio over a wide dyna mical range in mass. We conclude that the mass-to-light ratio has a minimum close t o the luminosity of an L* galaxy halo. We also show how

A. Lazarian, D. Pogosyan, Alejandro Esquivel

HI data cubes are sources of unique information on interstellar turbulence. Doppler shifts due to supersonic motions contain information on turbulent velocity field which is otherwise difficult to obtain. However, the problem of separation of velocity and density fluctuations within HI data cubes is far from being trivial. Analytical description of the emiss

Bon-Chul Koo, Jae-Joon Lee, Frederick D. Seward

We present the analysis of ASCA archival data from the Galactic source W51. The ASCA spectra show that the soft (kT<= 2.5 keV) X-rays are of thermal origin and are compatible with W51C being a single, isothermal (kT~0.3 keV) supernova remnant at the far-side of the Sagittarius arm. The ASCA images reveal hard (kT>=2.5 keV) X-ray sources which were not seen i

Jungyeon Cho, Alex Lazarian, Huirong Yan

Galactic HI is a gas that is coupled to magnetic field because of its fractional ionization. Many properties of HI are affected by turbulence. Recently, there has been a significant breakthrough on the theory of magnetohydrodynamic (MHD) turbulence. For the first time in the history of the subject we have a scaling model that is supported by numerical simula

G. Servant

We reanalyse the sphaleron bound of electroweak baryogenesis when allowing deviations to the Friedmann equation. These modifications are well motivated in the context of brane cosmology where they appear without being in conflict with major experimental constraints on four-dimensional gravity. While suppressed at the time of nucleosynthesis, these correction

Chung-Chuan Lo, Luis A. Nunes Amaral, Shlomo Havlin, Plamen Ch. Ivanov

We study the dynamics of the awakening during the night for healthy subjects and find that the wake and the sleep periods exhibit completely different behavior: the durations of wake periods are characterized by a scale-free power-law distribution, while the durations of sleep periods have an exponential distribution with a characteristic time scale. We find

Gary T. Horowitz, Ted Jacobson

It is well known that a weakly coupled U(N) gauge theory on a torus with sides of length L has extra light states with energies of order 1/NL. We show that a similar result holds for gauge theories on M/G where M is any compact Riemannian manifold and G is any freely acting discrete isometry group. As in the toroidal case, this is achieved by adding a suitab

Ted Jacobson, Stefano Liberati, David Mattingly

We analyze observational constraints from TeV astrophysics on Lorentz violating nonlinear dispersion for photons and electrons without assuming any a priori equality between the photon and electron parameters. The constraints arise from thresholds for vacuum Cerenkov radiation, photon decay and photo-production of electron-positron pairs. We show that the pa

Joydip Kundu, Krishna Rajagopal

We demonstrate that crystalline color superconductivity may arise as a result of pairing between massless quarks and quarks with nonzero mass m_s. Previous analyses of this phase of cold dense quark matter have all utilized a chemical potential difference δμto favor crystalline color superconductivity over ordinary BCS pairing. In any context in which crysta

Stacy McGaugh

I review what we currently do and do not know about the masses of disk galaxies and their dark matter halos. The prognosis for disks is good: the asymptotic rotation velocity provides a good indicator of total disk mass. The prognosis for halos is bad: cuspy halos provide a poor description of the data, and the total mass of individual dark matter halos rema

Ching-Tsai Lee, Yang Sun, Jing-ye Zhang, Mike Guidry

Recent experiments have confirmed the existence of rotational bands in the A \~ 110 mass region with very extended shapes lying between super- and hyper-deformation. Using the projected shell model, we make a first attempt to describe quantitatively such a band structure in 108Cd. Excellent agreement is achieved in the dynamic moment of inertia J(2) calculat

V. P. Frolov, D. V. Fursaev, D. N. Page

We consider thorny spheres, that is 2-dimensional compact surfaces which are everywhere locally isometric to a round sphere $S^2$ except for a finite number of isolated points where they have conical singularities. We use thorny spheres to generate, from a spherically symmetric solution of the Einstein equations, new solutions which describe spacetimes pierc

T. Antal, M. Droz, G. Gyorgyi, Z. Racz

The probability density function (PDF) of the roughness, i.e., of the temporal variance, of 1/f^alpha noise signals is studied. Our starting point is the generalization of the model of Gaussian, time-periodic, 1/f noise, discussed in our recent Letter [T. Antal et al., PRL, vol. 87, 240601 (2001)], to arbitrary power law. We investigate three main scaling re

Jerome Martin, Patrick Peter, Nelson Pinto Neto, Dominik J. Schwarz

By considering a simplified but exact model for realizing the ekpyrotic scenario, we clarify various assumptions that have been used in the literature. In particular, we discuss the new ekpyrotic prescription for passing the perturbations through the singularity which we show to provide a spectrum depending on a non physical normalization function. We also s

Gijs Verdoes Kleijn, Stefi Baum, Tim de Zeeuw, Christopher O&#39;Dea

In this paper we analyze the relation between radio, optical continuum and Halpha+[NII] emission from the cores of a sample of 21 nearby Fanaroff & Riley type I galaxies as observed with the VLBA and HST. The emission arises inside the inner tens of parsec of the galaxies. Core radio emission is observed in 19/20 galaxies, optical core continuum emission is

F. T. Brandt, Ashok Das, J. Frenkel

We study the behavior of the photon two point function, in non-commutative QED, in a general covariant gauge and in arbitrary space-time dimensions. We show, to all orders, that the photon self-energy is transverse. Using an appropriate extension of the dimensional regularization method, we evaluate the one-loop corrections, which show that the theory is ren

Steffen A. Bass

Strangeness production in microscopic transport models for relativistic heavy-ion collisions from SIS to RHIC is reviewed: after a brief introduction into elementary strangeness production processes, the main emphasis is put on strangeness as indicator of the nuclear equation of state, the excitation function of the $K^+/π^+$ ratio and strangeness as a decon

J. C. Montero, C. A. de S. Pires, V. Pleitez

In this work, using the fact that in 3-3-1 models the same leptonic bilinear contributes to the masses of both charged leptons and neutrinos, we develop an effective operator mechanism to generate mass for all leptons. The effective operators have dimension five for the case of charged leptons and dimension seven for neutrinos. By adding extra scalar multipl

B. Kyung, J. S. Landry, D. Poulin, A. -M. S. Tremblay

In a recent paper, Phys. Rev. Lett. 87, 167010/1-4 (2001), Moukouri and Jarrell presented evidence that in the two-dimensional (d=2) Hubbard model at half-filling there is a metal-insulator transition (MIT) at finite temperature even in weak coupling. While we agree with the numerical results of that paper, we arrive at different conclusions: The apparent ga

Horacio E. Castillo, Claudio Chamon, Leticia F. Cugliandolo, Malcolm P. Kennett

We introduce a set of theoretical ideas that form the basis for an analytical framework capable of describing nonequilibrium dynamics in glassy systems. We test the resulting scenario by comparing its predictions with numerical simulations of short-range spin glasses. Local fluctuations and responses are shown to be connected by a generalized local out-of-eq

I. Yurkevich

The purpose of this Lecture is to demonstrate how the well-known results on Luttinger Liquid can be obtained with the use of the coherent state integral.

P. Di Vecchia, H. Enger, E. Imeroni, E. Lozano-Tellechea

We compare two applications of the gauge/gravity correspondence to a non conformal gauge theory, based respectively on the study of D-branes wrapped on supersymmetric cycles and of fractional D-branes on orbifolds. We study two brane systems whose geometry is dual to N=4, D=2+1 super Yang-Mills theory, the first one describing D4-branes wrapped on a two-sphe

B. Enriquez, A. Odesskii

We introduce a quantization of the graded algebra of functions on the canonical cone of an algebraic curve C, based on the theory of formal pseudodifferential operators. When C is a complex curve with Poincaré uniformization, we propose another, equivalent construction, based on the work of Cohen-Manin-Zagier on Rankin-Cohen brackets. We give a presentation

Naresh Dadhich, Z. Ya. Turakulov

We obtain the most general solution of the Einstein electro - vacuum equation for the stationary axially symmetric spacetime in which the Hamilton-Jacobi and Klein - Gordon equations are separable. The most remarkable feature of the solution is its invariance under the duality transformation involving mass and NUT parameter, and the radial and angle coordina

M. I. Gorenstein, K. A. Bugaev, M. Gazdzicki

The transverse mass spectra of Omega, J/psi and psi&#39; in Pb+Pb collisions at 158 AGeV are studied within a hydrodynamical model of the quark gluon plasma expansion and hadronization. The model reproduces the existing data with the common hadronization parameters: temperature T=T_H = 170 MeV and average collective transverse velocity v_T = 0.2.

Sergey M. Klishevich, Mikhail S. Plyushchay

After a short discussion of the intimate relation between the generalized statistics and supersymmetry, we review the recent results on the nonlinear supersymmetry obtained in the context of the quantum anomaly problem and of the universal algebraic construction associated with the holomorphic nonlinear supersymmetry.

Asim K. Ray, Utpal Sarkar

We have studied the most general neutrino mass matrices in models with SU(2) and SU(3) horizontal symmetries. Without going into the details of the models it is possible to write down the effective operators, which predict the structure of the Majorana neutrino mass matrices. Unlike other extensions of the standard model, the structure is now independent of

Wojciech Broniowski, Wojciech Florkowski

Strange particle ratios and pT-spectra are calculated in a thermal model with single freeze-out, previously used successfully to describe non-strange particle production at RHIC. The model and the recently released data for phi, Lambda, anti-Lambda, and K*(892) are in very satisfactory agreement, showing that the thermal approach can be used to describe the

Shin-Tza Wu, Chung-Yu Mou

A generalized method of image is developed to investigate the tunneling spectrum from the metal into a class of states, with the tight-binding dispersion fully included. The broken reflection symmetry is shown to be the necessary condition for the appearance of the zero-bias conductance peak (ZBCP). Applying this method to the d-wave superconductor yields re

B. K. Patra, V. J. Menon

We consider the Brownian motion of a $c \bar c$ pair produced in the very early satge of a quark-gluon plasma. The one-dimensional Langevin equation is solved formally to get purely mechanical properties at small and large times. Stochastically-averaged variances are examined to extract the time scales associated with swelling and ionization of the bound sta

L. Giusti, A. Gonzalez-Arroyo, Ch. Hoelbling, H. Neuberger

We study Fermi fields defined on tori in the presence of gauge backgrounds carrying non-trivial topology. We show that 2k dimensional field space can alternatively be described by fields over a k-dimensional space. This dual description is particularly natural when the background is uniform and abelian. The reduction in number of dimensions carries over to t

G. Torrieri, J. Rafelski

We describe how the abundance and distribution of hyperon resonances can be used to probe freeze-out conditions. We demonstrate that resonance yields allow us to measure the time scales of chemical and thermal freeze-outs. This should permit a direct differentiation between the explosive sudden, and staged adiabatic freeze-out scenarios.

G. Giachetta, L. Mangiarotti, G. Sardanashvily

We provide geometric quantization of a completely integrable Hamiltonian system in the action-angle variables around an invariant torus with respect to polarization spanned by almost-Hamiltonian vector fields of angle variables. The associated quantum algebra consists of functions affine in action coordinates. We obtain a set of its nonequivalent representat

Robert H Brandenberger, Sergio E. Joras, Jerome Martin

In this paper, we calculate the spectrum of scalar field fluctuations in a bouncing, asymptotically flat Universe, and investigate the dependence of the result on changes in the physics on length scales shorter than the Planck length which are introduced via modifications of the dispersion relation. In this model, there are no ambiguities concerning the choi

A. A. Ezhov

The role of interference and entanglement in quantum neural processing is discussed. It is argued that on contrast to the quantum computing the problem of the use of exponential resources as the payment for the absense of entanglement does not exist for quantum neural processing. This is because of corresponding systems, as any modern classical artificial ne

Z. Y. Zeng, F. Claro

We investigate the delocalization and conductance quantization in finite one-dimensional chains with only off-diagonal disorder coupled to leads. It is shown that the appearence of delocalized states at the middle of the band under correlated disorder is strongly dependent upon the even-odd parity of the number of sites in the system. In samples with inversi

Zhongzhi Song, Kuang-Ta Chao

We present a perturbative QCD calculation of diffractive $D_s$ production in charged current deep inelastic scattering. In the two-gluon exchange model, we analyze the diffractive process $νN \to μ^- N \Ds$, which may provide useful information for the gluon structure of nucleons and the diffraction mechanism in QCD. The cross section of diffractive $D_s$ pr

J. D. Lejarreta, J. M. Cervero

In a previous paper, we have already considered the system composed by a two level atom interacting with a coherent external electromagnetic field. No application whatsoever has been made of the rotating wave approximation. Being specially interested in the problem of higher harmonic generations for the case of very intense laser fields, we have developed in

B. B. Blinov, L. Deslauriers, P. Lee, M. J. Madsen

We sympathetically cool a trapped 112Cd+ ion by directly Doppler-cooling a 114Cd+ ion in the same trap. This is the first demonstration of optically addressing a single trapped ion being sympathetically cooled by a different species ion. Notably, the experiment uses a single laser source, and does not require strong focusing. This paves the way toward reduci

Simon Saunders

Special relativity is most naturally formulated as a theory of space-time geometry, but within the space-time framework probability apears to be at best an epistemic notion - a matter of what can be known, not of the status of events in themselves. However, a non-epistemic account of probability can be given in Minkowski space-time, in terms of the Everett i

XuBo Zou, K. Pahlke, W. Mathis

We present a scheme to produce an entangled four-photon state from two pairs of entangled two-photon states. Such entangled four-photon states are equivalent to the quantum state of two maximally entangled spin-1 particles. The scheme can also be generated to prepare an entangled 2N-photon state from N pairs of entangled two-photon states. Such multi-photon