March 2003 arXiv papers — page 4

Wendelin Werner

We review some of the results that have been derived in the last years on conformal invariance, scaling limits and properties of some two-dimensional random curves. In particular, we describe the intuitive ideas that lead to the definition of the Schramm-Loewner evolutions SLE, we define these objects, study its various properties, show how to compute (proba

Patrick Bernard

We describe the asymptotic behaviour of solutions of unviscid Burgers equation on the circle with time-periodic forcing. These solutions converge to periodic states, but the period of these limit states may be greater than the period of the forcing. We obtain as a corollary a new result on the flow of the associated Hamiltonian system.

Sever Silvestru Dragomir

The median principle is applied for different integral inequalities of Gruss and Ostrowski type.

Alice Fialowski, Michael Penkava

We consider versal deformations of 0|3-dimensional L-infinity algebras, which correspond precisely to ordinary (non-graded) three dimensional Lie algebras. The classification of such algebras over C is well known, although we shall give a derivation of this classification using an approach of treating them as L-infinity algebras. Because the symmetric algebr

Michael C. Laskowski, Saharon Shelah

A class K of structures is controlled if for all cardinals lambda, the relation of L_{infty,lambda}-equivalence partitions K into a set of equivalence classes (as opposed to a proper class). We prove that no pseudo-elementary class with the independence property is controlled. By contrast, there is a pseudo-elementary class with the strict order property tha

Paul C. Eklof, Saharon Shelah

We consider what Ext(A,Z) can be when A is torsion-free and Hom(A,Z)=0. We thereby give an answer to a question of Golasinski and Goncalves which asks for the divisible Abelian groups which can be the type of a co-Moore space.

Wolfgang Ebeling, Sabir M. Gusein-Zade

We define a natural filtration on the ring ${\cal O}_{V,0}$ of germs of functions on a germ of a complex analytic variety $(V,0)$ related with the geometry of arcs on the variety and describe some properties of it.

Ranee Brylinski

We attach a Dixmier algebra B to the closure of any nilpotent orbit of G where G is GL(n,C), O(n,C) or Sp(2n,C). This algebra B is a noncommutative analog of the coordinate ring R of the orbit closure, in the sense that B has a G-invariant algebra filtration and gr B=R. We obtain B by making a noncommutative analog of the Kraft-Procesi construction which mod

Seif Randjbar-Daemi, Mikhail Shaposhnikov

Starting from an anomaly-free Abelian Higgs model coupled to gravity in a 6-dimensional space-time we construct an effective four-dimensional theory of charged fermions interacting with U(1) Abelian gauge field and gravity, both localised near the core of a Nielsen-Olesen vortex configuration. We show that an anomaly free theory in 6-dimensions can give rise

Luciano Barosi, Carlos Tello

We consider the $GSO(-)$ sector of the open superstring using the formalism with four-dimensional hybrid variables. This sector is defined by the world sheet hybrid variables $(θ^α,\barθ^{\dotα})$ with antiperiodic boundary conditions. The corresponding spectrum of states and conditions for physical vertices are described. In particular we construct explicit

Olalla A. Castro-Alvaredo, Andreas Fring

We provide new expressions for the scattering amplitudes in the soliton-antisoliton sector of the elliptic sine-Gordon model in terms of cosets of the affine Weyl group corresponding to infinite products of q-deformed gamma functions. When relaxing the usual restriction on the coupling constants, the model contains additional bound states which admit an inte

A. Vereshagin, V. Vereshagin, K. Semenov-Tian-Shansky

We consider the general properties of effective field theories. We note that the freedom to fix the renormalization conditions in the effective field theory is not as great as it seems. The consideration of minimal requirements of correctness of the perturbative scheme based on Dyson's formula for S-matrix leads to severe restriction on the essential par

Yoshinobu Habara

Using the idea of Itzykson-Zuber integral, unitary-matrix integration of 2D Yang-Mills action is presented. The uniqueness of the solution of heat equation enables us to integrate out the unitary-matrix parts of hermite matrices and to obtain the expression of integration over vectors, also in this case.

Shijong Ryang

Using the Schwarzschild-type coordinates in stead of the global ones we reconstruct the classical rotating closed string solutions in the AdS*5 x S*5 backgrounds. They are explicitly described by the Jacobi elliptic and trigonometrical functions of worldsheet coordinates. We study the orbiting closed string configurations in the near-horizon geometries of Dp

P. Bordalo, A. Wurtz

We realize the CFT with target a lens space SU(2)/Z_l as a simple current construction. This allows us to compute the boundary states and the annuli coefficients, and in particular to study the B-type branes, in purely algebraic terms. Several issues, like the appearance of fractional branes and symmetry breaking boundary conditions, can be addressed more di

Gudrid Moortgat-Pick

There exists a world--wide consensus for a future $e^+e^-$ Linear Collider in the energy range between $\sqrt{s}=500--1000$ GeV as the next large facility in HEP. The Linear Collider has a large physics potential for the discovery of new physics beyond the Standard Model and for precision studies of the Standard Model itself. It is well suited to complement

J. H. Kühn, C. Sturm, P. Uwer

Single top quark production in electron photon interactions provides a clean environment for the measurement of the Cabbibo-Kobayashi-Maskawa matrix element Vtb. Aiming an experimental precision at the percent level the knowledge of radiative corrections is important. In this paper we present results for the radiative corrections in quantum chromodynamics.

J. D. Vergados

Exotic dark matter together with the vacuum energy (cosmological constant) seem to dominate in the flat Universe. Thus direct dark matter detection is central to particle physics and cosmology. Supersymmetry provides a natural dark matter candidate, the lightest supersymmetric particle (LSP). It is possible to obtain detectable rates, but realystically they

Suvadeep Bose, Amitava Raychaudhuri

The K2K experiment has presented the first results on the observation of nu_mu. They show a depletion compared to the expectations and are consistent with neutrino oscillations with a mass-splitting in the range favoured by the Super-Kamiokande atmospheric neutrino measurements. Here we examine the extent by which the range of Delta m^2 obtained from the K2K

Elena Gubankova

This paper has been withdrawn by the author.

Jens Erler, Mingxing Luo

We present a new QCD sum rule with high sensitivity to the continuum regions of charm and bottom quark pair production. Combining this sum rule with existing ones yields very stable results for the msbar quark masses, m_c(m_c)$ and m_b (m_b). Comparison of our approach with experimental data allows for a robust theoretical error estimate. We have also provid

Hideo Nakajima, Sadataka Furui

The problem of color confinement in lattice Landau gauge QCD is briefly reviewed in the light of Kugo-Ojima criterion and Gribov-Zwanziger theory. The infrared properties of the Landau gauge QCD is studied by the measurement of the gluon propagator, ghost propagator, Kugo-Ojima parameter and the running coupling via $β=6.4,32^4,48^4$ lattice simulation. The

BABAR Collaboration, B. Aubert

Using events in which one of two neutral B mesons from the decay of an Y(4S) resonance is fully reconstructed, we set limits on the lifetime difference between the two neutral-B mass eigenstates and on CP, T, and CPT violation in B0-B0bar mixing. Both CP and non-CP eigenstates were obtained from the 88 million Y(4S)->B0B0bar decays collected between 1999 and

L3 Collaboration

A search for colour reconnection effects in hadronic decays of W pairs is performed with the L3 detector at centre-of-mass energies between 189 and 209 GeV. The analysis is based on the study of the particle flow between jets associated to the same W boson and between two different W bosons in qqqq events. The ratio of particle yields in the different interj

L3 Collaboration

The cross section of the process e+e- -> Ze+e is measured with 0.7fb^-1 of data collected with the L3 detector at LEP. Decays of the Z boson into quarks and muons are considered at centre-of-mass energies ranging from 183GeV up to 209GeV. The measurements are found to agree with Standard Model predictions, achieving a precision of about 10% for the hadronic

J. P. Krisch, E. N. Glass

We present an exact solution of Einstein's field equations in toroidal coordinates. The solution has three regions: an interior with a string equation of state; an Israel boundary layer; an exterior with constant isotropic pressure and constant density, locally isometric to anti-de Sitter spacetime. The exterior can be a cosmological vacuum with negative

Masato Minamitsuji, Yoshiaki Himemoto, Misao Sasaki

We consider a braneworld inflation model driven by the dynamics of a scalar field living in the 5-dimensional bulk, the so-called ``bulk inflaton model'', and investigate the geometry in the bulk and large scale cosmological perturbations on the brane. The bulk gravitational effects on the brane are described by a projection of the 5-dimensional Weyl

Bikash C. Gupta, Zhen Ye

We rigorously compute the propagation and scattering of microwaves by regular and defected arrays of dielectric cylinders in a uniform medium. Comparison with the previous experimental results is made, yielding agreements in the transmission coefficients for a certain range of frequencies. The results also show that localized states are possible for defected

C. Escudero, J. Buceta, F. J. de la Rubia, Katja Lindenberg

Using a model for rodent population dynamics, we study outbreaks of Hantavirus infection induced by the alternation of seasons. Neither season by itself satisfies the environmental requirements for propagation of the disease. This result can be explained in terms of the seasonal interruption of the relaxation process of the mouse population toward equilibriu

F. Claro, J. F. Weisz, S. Curilef

The correlated motion of electrons in a one dimensional system with an externally applied longitudinal electric field is discussed. Within the tight binding model we show that in addition to the well known Bloch oscillations the electron-electron interaction induces time dependent oscillations of the mobility whose period depends on the strength and range of

Mervlyn Moodley

Quantum Monte Carlo data are often afflicted with distributions that resemble lognormal probability distributions and consequently their statistical analysis can not be based on simple Gaussian assumptions. To this extent a method is introduced to estimate these distributions and thus give better estimates to errors associated with them. This method is appli

K. Ziegler

A grand-canonical system of interacting bosons is considered to study phase transitions of ultracold atoms in an optical lattice. The phase diagram is discussed in terms of a matrix-like order parameter, representing a symmetric phase (Mott insulator) and a symmetry-broken phase (Bose-Einstein condensate). An exact solution was found by introducing $N$ color

Jan Wilhelm, Erwin Frey

We study the elasticity of a two-dimensional random network of rigid rods (``Mikado model''). The essential features incorporated into the model are the anisotropic elasticity of the rods and the random geometry of the network. We show that there are three distinct scaling regimes, characterized by two distinct length scales on the elastic backbone.

Markus Kindermann, Yuli V. Nazarov

We review several ways of defining the statistics of charge that is transmitted through an electric circuit, the so-called "counting statistics". We first pursue two approaches that explain the origin of "negative probabilities" that have been found earlier in this context. The first analysis involves degrees of freedom of the electric circui

E. Helgren, N. P. Armitage, G. Gruner

Results of DC and frequency dependent conductivity in the quantum limit, i.e. hw > kT, for a broad range of dopant concentrations in nominally uncompensated, crystalline phosphorous doped silicon and amorphous niobium-silicon alloys are reported. These materials fall under the general category of disordered insulating systems, which are referred to as electr

M. Evangelisti, M. L. Kahn, J. Bartolome, L. J. de Jongh

We report on the low-temperature magnetic susceptibilities and specific heats of the isostructural spin-ladder molecular complexes L$_{2}$[M(opba)]$_{3\cdot x$DMSO$\cdot y$H$_{2}$O, hereafter abbreviated with L$_{2}$M$_{3}$ (where L = La, Gd, Tb, Dy, Ho and M = Cu, Zn). The results show that the Cu containing complexes (with the exception of La$_{2}$Cu$_{3}$

J. S. Caux, F. H. L. Essler, U. Loew

We consider the anisotropic Heisenberg spin-1/2 chain in a transverse magnetic field at zero temperature. We first determine all components of the dynamical structure factor by combining exact results with a mean-field approximation recently proposed by Dmitriev {\it et al}., JETP 95, 538 (2002). We then turn to the small anisotropy limit, in which we use fi

Marti Pi, Francesco Ancilotto, Enrico Lipparini

We generalize the Kohn's theorem to the case of parabolic three-dimensional quantum dots in magnetic fields of arbitrary direction. We show numerically that the exact resonance frequencies in the magneto-optical absorption of these dots are reproduced by the adiabatic time-dependent local spin density approximation theory (TDLSDA). We use TDLSDA to predi

A. P. Lyubartsev, M. Karttunen, I. Vattulainen, A. Laaksonen

We present a promising coarse-graining strategy for linking micro- and mesoscales of soft matter systems. The approach is based on effective pairwise interaction potentials obtained from detailed atomistic molecular dynamics (MD) simulations, which are then used in coarse-grained dissipative particle dynamics (DPD) simulations. Here, the effective potentials

S. E. Korshunov

The dependence of sheet impedance of a Josephson junction array on the applied magnetic field is investigated in the regime when vortex diffusion between array plaquettes is effectively frozen due to low enough temperature. The field dependent contribution to sheet inductance is found to be proportional to f*ln(1/f), where f<<1 is the magnitude of the field

J. Gonzalez

We apply a wilsonian renormalization group approach to the system of electrons in a two-dimensional square lattice interacting near the saddle-points of the band, when the correlations at momentum ${\bf Q} = (π, π)$ prevail in the system. The detailed consideration of the spin degrees of freedom allows to discern the way in which the SU(2) spin invariance is

J. -P. Onnela, A. Chakraborti, K. Kaski, J. Kertesz

This paper introduces a new methodology for constructing a network of companies called a dynamic asset graph. This is similar to the dynamic asset tree studied recently, as both are based on correlations between asset returns. However, the new modified methodology does not, in general, lead to a tree but a graph, or several graphs that need not be inter-conn

R. Rajesh, Deepak Dhar

We study fully convex polygons with a given area, and variable perimeter length on square and hexagonal lattices. We attach a weight t^m to a convex polygon of perimeter m and show that the sum of weights of all polygons with a fixed area s varies as s^{-theta_{conv}} exp[K s^(1/2)] for large s and t less than a critical threshold t_c, where K is a t-depende

A. Carpio, L. L. Bonilla

Wave front pinning and propagation in damped chains of coupled oscillators are studied. There are two important thresholds for an applied constant stress $F$: for $|F|<F_{cd}$ (dynamic Peierls stress), wave fronts fail to propagate, for $F_{cd} < |F| < F_{cs}$ stable static and moving wave fronts coexist, and for $|F| > F_{cs}$ (static Peierls stress) there

A. Imamoglu, E. Knill, L. Tian, P. Zoller

An all-optical scheme to polarize nuclear spins in a single quantum dot is analyzed. The hyperfine interaction with randomly oriented nuclear spins presents a fundamental limit for electron spin coherence in a quantum dot; by cooling the nuclear spins, this decoherence mechanism could be suppressed. The proposed scheme is inspired by laser cooling methods of

J. E. Hirsch, D. J. Hirsch

A permanent magnet levitating over a superconductor is found to spontaneously spin, overcoming resistance to air friction. We explain the physics behind this remarkable effect.

M. Amin Kayali, Valery L. Pokrovsky

We study the transport properties of vortex matter in a superconducting thin film separated by a thin insulator layer from a ferromagnetic layer. We assume an alternating stripe structure for both FM and SC layers as found in [7]. We calculate the periodic pinning force in the stripe structure resulting from a highly inhomogeneous distribution of the vortice

M. Yogi, H. Kotegawa, Y. Imamura, G. -q. Zheng

We report the electronic and superconducting properties in the Pr-based filled-skutterudite superconductor PrRu$_4$Sb$_{12}$ with $T_c = 1.3$ K via the measurements of nuclear-quadrupole-resonance (NQR) frequency $ν_Q$ and nuclear-spin-lattice-relaxation time $T_1$ of Sb nuclei. The temperature dependence of $ν_Q$ has revealed the energy scheme of Pr$^{3+}$

H. F. Coronel-Brizio, C. R. de la Cruz-Laso, A. R. Hernandez-Montoya

In the spirit of the emergent field of econophysics, a goodness-of-fit test for the Power-Law distribution, based on the Empirical Distribution Function (EDF) is presented, and related problems are discussed. An analysis of the tail behaviour of the daily logarithmic variation of the Mexican Stock Market Index (IPC), showed distributional properties which ar

Sachin Parashar, A. R. Raju, C. N. R. Rao, P. Victor

YMnO3 thin films were grown on n - type Si substrate by nebulized spray pyrolysis in Metal - Ferroelectric - Semiconductor (MFS) configuration. The C-V characteristics of the film in MFS structure exhibit hysteretic behavior consistent with the polarization charge switching direction, with the memory window decreasing with increase in temperature. The densit

A. H. Castro Neto, E. Novais, L. Borda, Gergely Zarand

We discuss the problem of a spin 1/2 impurity immersed in a spin S magnetically ordered background. We show that the problem maps onto a generalization of the dissipative two level system (DTLS) with two independent heat baths, associated with the Goldstone modes of the magnet, that couple to different components of the impurity spin operator. Using analytic

Gustavo A. Narvaez, George Kirczenow

By extending the Orthodox theory of Coulomb blockade to include the nano-scale effects of environmental electric fields, we show that tunneling spectra of metallic nanoislands contain information not only on the energies of the electronic levels but also on their wavefunctions near the surface of the island. This fundamental additional information is predict

Sumiyoshi Abe, Norikazu Suzuki

The district of southern California and Japan are divided into small cubic cells, each of which is regarded as a vertex of a graph if earthquakes occur therein. Two successive earthquakes define an edge and a loop, which replace the complex fault-fault interaction. In this way, the seismic data are mapped to a random graph. It is discovered that an evolving

Shan-Wen Tsai, J. B. Marston

Motivated by experiments on the layered compounds $κ$-(BEDT-TTF)$_2$X, Cs$_2$CuCl$_4$, and very recently Na$_x$CoO$_2 \cdot y$H$_2$O, we present a weak-coupling functional renormalization-group analysis of the Hubbard model on the anisotropic triangular lattice. As the model interpolates between the nearest-neighbor square lattice and decoupled chains via th

Lisa J. Storrie-Lombardi, Ray J. Weymann, Rodger I. Thompson

We present results on two related topics: 1. A discussion of high redshift candidates (z>4.5), and 2. A study of very small galaxies at intermediate redshifts, both sets being detected in the region of the northern Hubble Deep Field covered by deep NICMOS observations at 1.6 and 1.1 microns. The high redshift candidates are just those with redshift z>4.5 as

Almudena Alonso-Herrero, Alice C. Quillen, George H. Rieke, Valentin D. Ivanov

We present nuclear spectral energy distributions (SEDs) in the range 0.4-16micron for an expanded CfA sample of Seyfert galaxies. The spectral indices from 1-16micron range from alpha_IR 0.9 to 3.8. The shapes of the spectra are correlated with Seyfert type in the sense that steeper nuclear SEDs (nu*f_nu increasing with increasing wavelength) tend to be foun

Daniel Thomas, Claudia Maraston, Ralf Bender

We use our new stellar population models, which include effects from variable element abundance ratios, to model the Ca4227 absorption line indices of early-type galaxies (Trager et al.), and to derive calcium element abundances. We find that calcium, although being an alpha-element, is depressed with respect to the other alpha-elements by up to a factor 2.

Lev Kofman

Superstring theory, models with extra dimensions and other SUSY models generically predict that the coupling constants are in fact vacuum expectation values of fields like the dilaton, moduli etc. Assuming some of these fields are light during inflation, we get generation of small classical inhomogeneities in these fields from inflation. Consequently, coupli

Gerardo Dominguez, Andrew J. Westphal, Mark L. F. Phillips, Steven M. Jones

Contemporary interstellar dust has never been analyzed in the laboratory, despite its obvious astronomical importance and its potential as a probe of stellar nucleosynthesis and galactic chemical evolution. Here we report the discovery of a novel fluorescent aerogel which is capable of capturing hypervelocity dust grains and passively recording their kinetic

J. A. Sellwood, Juntai Shen

Any connection between central activity and the large-scale dynamics of disk galaxies requires an efficient mechanism to remove angular momentum from the orbiting material. The only viable means of achieving inflow from kiloparsec scales is through gravitational stresses created by bars and/or mergers. The inflow of gas in bars today appears to stall at a ra

Africa Castillo-Morales, Sabine Schindler

We present the analysis of baryonic and non-baryonic matter distribution in a sample of ten nearby clusters ($0.03<z<0.09$) with temperatures between 4.7 and 9.4 keV. These galaxy clusters have been studied in detail using X-ray data and global physical properties have been determined. Correlations between these quantities have been analysed and compared wit

Africa Castillo-Morales, Sabine Schindler

Clusters of galaxies are used in a variety of ways to do cosmology. Some of them are presented here. Their X-ray emitting gas allows us to determine the baryon fraction, dark matter distribution and the matter density $Ω_{m}$ of the universe. Another interesting component is relativistic particles whose radio emission provide the measure of the magnetic fiel

Michal Hanasz, Harald Lesch

We investigate favourable circumstances for fast magnetic reconnection in astrophysical plasmas based on recent results by Rogers et al. (2001). Given that a critical magnetic field structure with antiparallel field lines exists, our analysis demonstrates that a sufficient condition for fast reconnection is that the ratio of the thermal pressure to the magne

M. Schultheis, A. Lançon, A. Omont, F. Schuller

In this work we present near-IR spectra (HK-band) of a sample of 107 sources with mid-IR excesses at 7 and 15 $\rm μ$m detected during the ISOGAL survey. Making use of the DENIS interstellar extinction map from Schultheis et al. (1999) we derive luminosities and find that the $\rm M_{bol}$ vs.~$\rm ^{12}CO$ and $\rm M_{bol} vs. H_{2}O$ diagrams are powerful

M. T. Menna, L. Burderi, L. Stella, N. Robba

We detect a significant broadening in the wings of the 401 Hz peak in the power spectrum of the accreting millisecond binary pulsar SAX J1808.4-3658. This feature is consistent with the convolution of the red noise present in the power spectrum with the harmonic line. We conclude that the flux modulated by the spin period shows aperiodic variability similar

M. Clampin, J. E. Krist, D. R. Ardila, D. A. Golimowski

Multicolor coronagraphic images of the circumstellar disk around HD141569A have been obtained with the Hubble Space Telescope (HST) Advanced Camera for Surveys. B, V, and I images show that the disk&#39;s previously-described multiple-ring structure is actually a continuous distribution of dust with a tightly-wound spiral structure. Two, more open spiral arm

Andria Rogava, Gianluigi Bodo, Silvano Massalgia, Zaza Osmanov

Recently it was found that helical magnetized flows efficiently amplify Alfvén waves (Rogava et al. 2003, A&A, v.399, p.421). This robust and manifold nonmodal effect was found to involve regimes of transient algebraic growth (for purely ejectional flows), and exponential instabilities of both usual and parametric nature. However the study was made in the in

Andria Rogava, George Dalakishvili, Zaza Osmanov

Motion of test particles along rotating curved trajectories is considered. The problem is studied both in the laboratory and the rotating frames of reference. It is assumed that the system rotates with the constant angular velocity $ω= const$. The solutions are found and analyzed for the case when the form of the trajectory is given by an Archimedes spiral.

L. Origlia, F. R. Ferraro, M. Bellazzini, E. Pancino

Near-infrared spectra of 21 giants in omega Centauri, spanning the whole range of metallicities observed in this cluster, are presented. This work is part of a coordinated photometric and spectroscopic campaign in the optical and in the infrared, aimed at studying the complex stellar population of omega Centauri and understanding its formation and chemical e

Mikio Morii, Rie Sato, Jun Kataoka, Nobuyuki Kawai

We present the results from the {\it Chandra} ACIS CC mode observation of an anomalous X-ray pulsar (AXP) 1E 1841-045. This is the first observation in which the pulsar spectrum in wide energy range is spatially discriminated from the surrounding SNR, Kes 73. Like other AXPs, the phase-integrated spectrum is fitted well with power-law plus blackbody model. T

E. Buchlin, V. Aletti, S. Galtier, M. Velli

A 3D model intermediate between cellular automata (CA) models and the reduced magnetohydrodynamic (RMHD) equations is presented to simulate solar impulsive events generated along a coronal magnetic loop. The model consists of a set of planes distributed along a magnetic loop between which the information propagates through Alfven waves. Statistical propertie

W. Becker, B. Aschenbach

The X-ray Multi-Mirror Mission XMM-Newton is ESA&#39;s largest observatory so far; it is dedicated to explore the Universe in the 0.2 - 15 keV X-ray band of the electromagnetic spectrum. Because of its large collecting area very faint sources not accessible before can be observed and it is therefore the long awaited instrument to study young pulsars and neut

K. L. Vaninsky

We consider the integrable Camassa--Holm equation on the line with positive initial data rapidly decaying at infinity. On such phase space we construct a one parameter family of integrable hierarchies which preserves the mixed spectrum of the associated string spectral problem. This family includes the CH hierarchy. We demonstrate that the constructed flows

Dag Østvang

The quasi-metric manifold $\cal N$ is equipped with two one-parameter families of metric tensors ${\bf {\bar g}}_t$ and ${\bf g}_t$, each parametrized by the global time function $t$. Moreover, in $({\cal N},{\bf {\bar g}}_t)$ one must define two different electromagnetic field tensor families corresponding to the active electromagnetic field tensor family $

S. L. Dubovsky, S. M. Sibiryakov

Noncommutative U(N) gauge theories at different N may be often thought of as different sectors of a single theory: the U(1) theory possesses a sequence of vacua labeled by an integer parameter N, and the theory in the vicinity of the N-th vacuum coincides with the U(N) noncommutative gauge theory. We construct noncommutative domain walls on fuzzy cylinder, s

R. Narayanan, H. Neuberger

Numerical and theoretical evidence leads us to propose the following: Three dimensional Euclidean Yang-Mills theory in the planar limit undergoes a phase transition on a torus of side $l=l_c$. For $l>l_c$ the planar limit is $l$-independent, as expected of a non-interacting string theory. We expect the situation in four dimensions to be similar.

Nihat Sadik Deger

We construct new intersecting S-brane solutions in 11-dimensional supergravity which do not have supersymmetric analogs. They are obtained by letting brane charges to be proportional to each other. Solutions fall into two categories with respect to whether there is a non-diagonal term to be cancelled in the field equations or not. In each case we show that t

E. S. Battistelli, M. De Petris, L. Lamagna, G. Luzzi

The Sunyaev-Zeldovich (SZ) effect was previously measured in the Coma cluster by the Owens Valley Radio Observatory and Millimeter and IR Testa Grigia Observatory experiments and recently also with the Wilkinson Microwave Anisotropy Probe satellite. We assess the consistency of these results and their implications on the feasibility of high-frequency SZ work

Kenji Fukushima

We discuss the relation between the Polyakov loop and the chiral order parameter at finite temperature by using the Gocksch-Ogilvie model with fundamental or adjoint quarks. The model is based on the double expansion of strong coupling and large dimensionality on the lattice. In an analytic way with the mean field approximation employed, we show that the con

Gabriele De Chiara, G. Massimo Palma

The effect of fluctuations in the classical control parameters on the Berry phase of a spin 1/2 interacting with a adiabatically cyclically varying magnetic field is analyzed. It is explicitly shown that in the adiabatic limit dephasing is due to fluctuations of the dynamical phase.

Jean-Philippe Uzan, Alain Riazuelo, Roland Lehoucq, Jeffrey Weeks

This article describes the Cosmic Microwave Background anisotropies expected in a closed universe with the topology of a lens space L(p,q) and with density parameter Omega_0 close to 1. It provides the first simulated maps for such spaces along with their corresponding power spectra. In spite of our initial expectations that increasing p (and thus decreasing

Ping Sun, Gabriel Kotliar

We investigate the competition of the Kondo and the RKKY interactions in heavy fermion systems. We solve a periodic Anderson model using Extended Dynamical Mean Field Theory (EDMFT) with QMC. We monitor simultaneously the evolution of the electronic and magnetic properties. As the RKKY coupling increases the heavy fermion quasiparticle unbinds and a local mo

Zygmunt Lalak, Radoslaw Matyszkiewicz

We have extended previous analysis of the bulk/brane supersymmetrizations involving non-zero brane mass terms of bulk fermions (gravitini) and twisting of boundary conditions. We have constructed new brane/bulk models that may be relevant for realistic model building. In particular, we have built a model with the Randall-Sundrum bosonic sector, orthogonal pr

Cristina Volpe

A novel method to produce neutrino beams has recently been proposed : the beta-beams. This method consists in using the beta-decay of boosted radioactive nuclei to obtain an intense, collimated and pure neutrino beam. Here we propose to exploit the beta-beam concept to produce neutrino beams of low energy. We discuss the applications of such a facility as we

S. Kondratyuk, K. Kubodera, F. Myhrer

Since the existing calculations of the effective meson mass in nuclear medium involve approximations, it is important to examine whether they satisfy the general requirement of the equivalence theorem that the physical observables should be independent of the choice of field variables. We study here consequences of nucleon field transformations. As an illust

C. D. Fosco, A. Lopez

We evaluate the fermion propagator in parity-conserving QED_3 with N flavours, in the context of an IR domain approximation. This provides results which are non-perturbative in the loopwise expansion sense. We include fermion-loop effects, and show that they are relevant to the chiral symmetry breaking phenomenon, that can be understood in this context.

James Lucietti

The classical theory for a massive free particle moving on the group manifold $AdS_3 \cong SL(2, \mathbb{R})$ is analysed in detail. In particular a symplectic structure and two different sets of canonical coordinates are explicitly found, corresponding to the Cartan and Iwasawa decomposition of the group. Canonical quantization is performed in two different

Dominik J. Schwarz

The history of the Universe after its first second is now tested by high quality observations of light element abundances and temperature anisotropies of the cosmic microwave background. The epoch of the first second itself has not been tested directly yet; however, it is constrained by experiments at particle and heavy ion accelerators. Here I attempt to de

Roberto Gomez, Simonetta Frittelli

We prescribe a choice of 18 variables in all that casts the equations of the fully nonlinear characteristic formulation of general relativity in first--order quasi-linear canonical form. At the analytical level, a formulation of this type allows us to make concrete statements about existence of solutions. In addition, it offers concrete advantages for numeri

Jianqiang Zhao

In this note we shall improve some congruences of D.F. Bailey [Two p^3 variations of Lucas&#39; Theorem, JNT 35(1990), pp. 208-215] to higher prime power moduli, by studying the relation between irregular pairs of the form (p,p-3) and refined version of Wolstenholme&#39;s theorem.

V. Hnizdo

A flaw is pointed out in the justification given by Charitat and Graner [2003 Eur. J. Phys. vol. 24, 267] for the use of the Biot--Savart law in the calculation of the magnetic field due to a straight current-carrying wire of finite length.

N. Mankoc Borstnik, H. B. Nielsen

Using a technique \cite{holgernorma2002} to construct a basis for spinors and ``families&#39;&#39; of spinors in terms of Clifford algebra objects, we define other Clifford algebra objects, which transform the state of one &#39;&#39;family&#39;&#39; of spinors into the state of another &#39;&#39;family&#39;&#39; of spinors, changing nothing but the &#39;&#39

B. Chandrasekhar, Alok Kumar

The cubic interaction vertex and the dynamical supercharges are constructed for open strings ending on D7-branes, in light-cone superstring field theory in PP-wave background. In this context, we write down the symmetry generators in terms of the relevant group structure: SU(2) x SU(2) x SO(2) x SO(2), originating from the eight transverse directions in the

G. Agakichiev

Elliptic flow and two-particle azimuthal correlations of charged hadrons and high-$p_T$ pions ($p_T>$ 1 GeV/$c$) have been measured close to mid-rapidity in 158A GeV/$c$ Pb+Au collisions by the CERES experiment. Elliptic flow ($v_2$) rises linearly with $p_T$ to a value of about 10% at 2 GeV/$c$. Beyond $p_T\approx$ 1.5 GeV/$c$, the slope decreases considera

Shi Zhou, Raul J. Mondragon

The Internet topology at the Autonomous Systems level (AS graph) has a power--law degree distribution and a tier structure. In this paper, we introduce the Interactive Growth (IG) model based on the joint growth of new nodes and new links. This simple and dynamic model compares favorable with other Internet power--law topology generators because it not only

M. Itakura

Extensive Monte Carlo simulations are used to investigate the low-temperature properties of the random anisotropy Heisenberg model, which describes the magnetic behavior of amorphous rare-earth-transition metal alloy. We show that the low-temperature phase in weak-anisotropy region is characterized by a {\it frozen-in} power-law spin-spin correlation. Numeri

T. Zwitter, U. Munari, P. M. Marrese, A. Prsa

The orbits and physical parameters of three close, double-lined G0 eclipsing binaries have been derived combining H_P, V_T, B_T photometry from the Hipparcos/Tycho mission with 8480-8740 Åground-based spectroscopy. The setup is mimicking the photometric and spectroscopic observations that should be obtained by GAIA. The binaries considered here are all of G0

F. S. Bergeret, A. F. Volkov, K. B. Efetov

We study proximity effects in a multilayered superconductor/ferromagnet (S/F) structure with arbitrary relative directions of the magnetization ${\bf M}$. If the magnetizations of different layers are collinear the superconducting condensate function induced in the F layers has only a singlet component and a triplet one with a zero projection of the total ma

Christophe Chatelain

We derive an exact expression of the response function to an infinitesimal magnetic field for an Ising-Glauber-like model with arbitrary exchange couplings. The result is expressed in terms of thermodynamic averages and does not depend on the initial conditions or on the dimension of the space. The response function is related to time-derivatives of a compli

L. Nivanen, A. Le Mehaute, Q. A. Wang

By considering generalized logarithm and exponential functions used in nonextensive statistics, the four usual algebraic operators : addition, subtraction, product and division, are generalized. The properties of the generalized operators are investigated. Some standard properties are preserved, e.g., associativity, commutativity and existence of neutral ele