bluuebunny/crossref_metadata_2025 huggingface dataset:
DESIGNING A CONNECTIONIST NETWORK SUPERCOMPUTER
Authors: ASANOVIĆ KRSTE , BECK JAMES , FELDMAN JERRY , MORGAN NELSON , WAWRZYNEK JOHN
Published: November 2004

This paper describes an effort at UC Berkeley and the International Computer Science Institute to develop a supercomputer for artificial neural network applications. Our perspective has been strongly influenced by earlier experiences with the construction and use of a simpler machine. In particular, we have observed Amdahl's Law in action in our designs and those of others. These observations inspire attention to many factors beyond fast multiply-accumulate arithmetic. We describe a number of these factors along with rough expressions for their influence and then give the applications targets, machine goals and the system architecture for the machine we are currently designing.
AN ARCHITECTURE FOR FULLY INTEGRATED LARGE SCALE NEURAL NETWORKS
Authors: BINNS M. D. , CLOUGH F. J. , GARTH S. C. J.
Published: November 2004

To apply neural networks to many engineering applications, large networks will be required. Such networks are difficult to build using standard crystalline silicon technology due to limitations in both the fabrication and packaging processes. An architecture is proposed where amorphous silicon photoresistors are used to store the synaptic weights. A single plate of amorphous silicon is able to contain up to 100 million photoresistors, exploiting readily available fabrication technology. Using an external light source, each photoresistor can be individually adjusted allowing them to be configured as programmable fixed-value resistors. The processing compatibility of polysilicon and amorphous silicon allows the same glass substrate to be used for large-area integration of the photosensors, the analogue neural network and the neurons. The integration of the photosensors and the rest of the network may be used to alleviate the interface problem at the inputs resulting in a design with a very simple architecture that is both elegant and simple to fabricate. This paper describes such a design in which amorphous silicon technology is applied to neural network hardware.
ANALOG CIRCUITS FOR RELAXATION NETWORKS
Authors: CARD HOWARD
Published: November 2004

Selected examples are presented of recent advances, primarily from the U.S. and Canada, in analog circuits for relaxation networks. Relaxation networks having feedback connections exhibit potentially greater computational power per neuron than feedforward networks. They are also more poorly understood especially with respect to learning algorithms. Examples are described of analog circuits for (i) supervised learning in deterministic Boltzmann machines, (ii) unsupervised competitive learning and feature maps and (iii) networks with resistive grids for vision and audition tasks. We also discuss recent progress on in-circuit learning and synaptic weight storage mechanisms.
KAKADU — A LOW POWER ANALOGUE NEURAL NETWORK CLASSIFIER
Authors: LEONG PHILIP H. W. , JABRI MARWAN A.
Published: November 2004

An analogue neural network VLSI chip designed for low power operation is presented. This chip consists of 84 synapse elements arranged as arrays of size 10 × 6 and 6 × 4 and was fabricated using a standard 1.2 μm double metal single poly CMOS process. The synapses are digitally programmable and static weight storage is provided. The chip has a typical power consumption of tens of microwatts. It has been successfully trained and tested on a range of classification problems including 4-bit parity, character recognition and morphological-based classification of intracardiac electrogram signals.
PULSE STREAM VLSI CIRCUITS AND SYSTEMS: THE EPSILON NEURAL NETWORK CHIPSET
Authors: HAMILTON ALISTER , CHURCHER STEPHEN , EDWARDS PETER J. , JACKSON GEOFFREY B. , MURRAY ALAN F. , REEKIE H. MARTIN
Published: November 2004

An analogue CMOS VLSI neural processing chip has been designed and fabricated. The device employs "pulse-stream" neural state signalling and is capable of computing some 360 million synaptic connections per second. In addition to basic characterisation results, the performance of the chip in solving "real-world" problems is also demonstrated. The experience gained from the development of this device has resulted in the design of a second "pulse-stream" chip with improved performance and features. It is anticipated that this second device will be integrated into a standard bus-based system and find early application in robotic control.
DETECTION LIMIT FOR A VERY THIN BACKING FILM
Authors: ISHII KEIZO , ORIHARA HIKONOJO , IWATA YOSHIHIRO , BESSHO KOTARO
Published: November 2004

Detection limit for thin backing films is formulated. A polyvinyl formal film of ~ 0.14µm was bombarded with 3 MeV protons and continuos backgrounds were measured with a Si(Li) detector. A large constant background of a high energy region (≥6 keV ) was interpreted as the Compton tail due to the 440 keV γ-rays from the excited state of 23Na which contaminated the surface of a carbon collimator placed just in front of a target. The detection limits of this thin film, under the condition of the beam spot size 6 mmϕ without collimator, are estimated for the elements of atomic number Z=10~55 and the minimum detection limit is calculated to be 4×10−12 g for Z=28~34.
PIXE ANALYSIS OF MINERAL COMPOSITION OF ALFALFA ROOT-TIP EXPOSED TO LOW PH OR ALUMINUM STRESS CONDITION
Authors: YOKOTA SATOSHI , ISHII KEIZO , MAE TADAHIKO , OJIMA KUNIHIKO
Published: November 2004

PIXE analysis was applied to study alteration of mineral composition (Al, P, K, and Cl) of alfalfa root-tip exposed to low pH or aluminum stress. These minerals were detectable using one or two pieces of root-tips. Short-term (within 4 h) decreases in K/P and Cl/P ratios were observed under low pH and aluminum stress conditions. However, degree of the decrease was not same. Differences in toxic effects of low pH and Al on the root-tip of alfalfa are discussed.
HIGH SPEED SEMICONDUCTOR LASERS
Authors: NAGARAJAN RADHAKRISHNAN , TAUBER DANIEL , BOWERS JOHN E.
Published: November 2004

The strategy and methods to design high speed semiconductor lasers are reviewed here. The formalism for the analysis of intensity modulation, frequency modulation and intensity noise in quantum well lasers is first derived. Using this formalism the process of optimizing the laser structure for high speed operation is presented. In addition to the conventional factors such as the differential gain, photon density, photon lifetime and device parasitics, we also review the critical effects of carrier transport and microwave signal transmission on the dynamic characteristics and design of high speed semiconductor lasers.
THE DESIGN AND FABRICATION OF HIGH-SPEED HBT CIRCUITS FOR FIBER-OPTIC COMMUNICATION SYSTEMS
Authors: OBARA MASAO , AKAGI JUNKO
Published: November 2004

AlGaAs/GaAs heterojunction bipolar transistor (HBT) high speed ICs have been paving the way for the most sophisticated fiber-optic communication systems since the late 1980s. Recently 20 Gbps HBT ICs have been developed to accommodate the emergence of optical fiber amplifiers. HBT technology is now proceeding towards the development of 40 Gbps systems where the lack of high speed measurement system remains an issue.
GaInAsP/InP VERTICAL CAVITY SURFACE EMITTING LASERS IN 1.3 and 1.5 μm-WAVELENGTH BAND
Authors: IGA KENICHI
Published: November 2004

We review the recent progress of vertical cavity surface emitting lasers operating at 1.3 μm and 1.55 μm wavelength band, which are attractive for future parallel optical communication systems. The key issues for improving their lasing characteristics are discussed, including high reflective mirrors, thermal problems, current confining structures and so on.
VERTICAL CAVITY SURFACE EMITTING LASER ARRAYS FOR WAVELENGTH DIVISION MULTIPLEXING APPLICATIONS
Authors: CHANG-HASNAIN C.J. , WU Y.A. , ENG L.E. , LI G.S.
Published: November 2004

The capability to fabricate two-dimensional (2D) semiconductor diode laser array is one of the most important steps towards making wafer-scale low-cost lasers. The recent emergence of vertical cavity surface emitting laser (VCSEL) facilitates the fabrication of such large 2D arrays. In this paper, we review the recent progress on a novel largeaperture single-mode VCSEL and a 2D multiple-wavelength VCSEL array for ultra-high bandwidth applications. We demonstrate a passive antiguide region (PAR) VCSEL which emits a stable single mode with very low threshold, a large aperture, and a fixed polarization. We also demonstrate multi-wavelength VCSEL arrays with repeatable wavelength spans over 20 nm, grown by Molecular Beam Epitaxy. The wavelength shift is achieved by varying the GaAs growth rate across the wafer using a patterned backing wafer to induce a temperature profile. Such multiple wavelength laser arrays are promising for ultrahigh bandwidth optical transmission and switching systems using wavelength division multiplexing (WDM).
INFORMATION BROADCASTING BY EXCLUSIVE-READ PRAMS
Authors: BEAME PAUL , KUTYŁOWSKI MIROSŁAW , KIK MARCIN
Published: November 2004

We consider the problem of copying information stored initially in a single memory cell by Exclusive Read Exclusive Write Parallel Random Access Machines (EREW PRAMs). We prove lower bounds for this problem and present algorithms matching them tightly (in many cases up to an additive constant). The bounds presented depend on the number of cells used and size of information copied. The lower bounds apply also to functions where a change of a single argument influences the output in many memory locations.
DATA COMPILING FOR SYSTEMS OF UNIFORM RECURRENCE EQUATIONS
Authors: MONGENET CATHERINE
Published: November 2004

This paper presents techniques to compile systems of recurrence equations into parallel programs defined by a set of virtual processors connected via a regular network and by the communications between these processors. These techniques are founded on a dependency analysis. The data dependencies are automatically compiled either in local memory management or in communications between the virtual processors through send/receive channels.
ON PARALLEL PREFIX COMPUTATION
Authors: SAXENA SANJEEV , BHATT P.C.P. , PRASAD V.C.
Published: November 2004

We prove that prefix sums of n integers of at most b bits can be found on a COMMON CRCW PRAM in [Formula: see text] time with a linear time-processor product. The algorithm is optimally fast, for any polynomial number of processors. In particular, if [Formula: see text] the time taken is [Formula: see text]. This is a generalisation of previous result. The previous [Formula: see text] time algorithm was valid only for O(log n)-bit numbers. Application of this algorithm to r-way parallel merge sort algorithm is also considered.

We also consider a more realistic PRAM variant, in which the word size, m, may be smaller than b (m≥log n). On this model, prefix sums can be found in [Formula: see text] optimal time.
ONE-LOOP DIVERGENCES IN TWO-DIMENSIONAL MAXWELL-DILATON QUANTUM GRAVITY
Authors: ELIZALDE E. , ODINTSOV S.D.
Published: November 2004

Two-dimensional Maxwell-dilaton quantum gravity, which covers a large family of the actions for two-dimensional gravity (in particular, string-inspired models) is investigated. Charged black holes which appear in the theory are briefly discussed. The one-loop divergences in the linear covariant gauges are calculated. It is shown that for some choices of the dilaton potential and dilaton-Maxwell coupling, the theory is one-loop multiplicatively renormalizable (or even finite). A comparison with the divergences structure of four-dimensional Einstein-Maxwell gravity is given.
SUPERSYMMETRIC SOLUTION FOR TWO-DIMENSIONAL SCHRÖDINGER EQUATION
Authors: FILHO ELSO DRIGO
Published: November 2004

We use a non usual realization of the superalgebra to resolve certain two-dimensional potentials. The Hartmann and an anisotropic ring-shaped oscillator are explicitly solved.
THE SCALE WHERE SUPERSYMMETRY BREAKS: A NEW PARAMETER IN UNIFIED MODELS
Authors: KELLEY S. , LOPEZ JORGE L. , NANOPOULOS D.V.
Published: November 2004

We examine supersymmetry breaking in string-inspired models through gaugino condensation in the hidden sector. With the physically sensible assumption that observable supersymmetry breaking effects turn off above the gaugino condensation scale (Λh), we derive a realistic range for the scale where supersymmetry breaks (1012 GeV<ΛSUSY= Λh<1016 GeV) which should be contrasted with the usual identification of ΛSUSY with the gauge coupling unification scale. We also derive constraints on the hidden sector to be consistent with this ΛSUSY range and to allow supersymmetry breaking with a perturbative gauge coupling in two-gaugino-condensate models. We then establish ΛSUSY as a new parameter in two unified models, the supersymmetric standard model (SSM), and the string-inspired standard model (SISM). We briefly review the two models, examining radiative electroweak breaking and the resulting phenomenology to determine allowed regions in parameter space as a function of ΛSUSY for a few representative cases. We also propose an algebraic combination of sparticle masses, which only depends on ΛSUSY, as a means of experimentally determining the scale at which supersymmetry breaks.
FERMION-BOSON SCATTERING IN LADDER APPROXIMATION
Authors: JAFAROV R.G. , HADJIEV S.A.
Published: November 2004

A method of calculating the forward scattering amplitude for fermions and scalar bosons with the exchange of scalar particle is suggested. The Bethe-Salpeter ladder equation for the imaginary part of the amplitude is constructed and a solution in Regge asymptotical form is found and the corrections to the amplitude due to the exit from mass shell are calculated.
MIXED MODEL OF INDUCED QCD
Authors: MIGDAL A.A.
Published: November 2004

The problems with the ZN symmetry breaking in the induced QCD are analyzed. We compute the Wilson loops in the strong coupling phase, but we do not find the ZN symmetry breaking, for arbitrary potential. We suggest to bypass this problem by adding to the model a heavy fermion field in a fundamental representation of SU(N). Remarkably, the model can still be solved exactly by the Riemann-Hilbert method, for arbitrary number of flavors, Nf. At Nf≪N→∞ there is a new regime, with two vacuum densities. The ZN symmetry breaking density satisfies the linear integral equation, with the kernel, depending on the old density. The symmetry breaking requires certain eigenvalue condition, which takes some extra parameter adjustment of the scalar potential.
STRONG GRAVITY APPROACH TO QCD AND CONFINEMENT
Authors: SALAM ABDUS , SIVARAM C.
Published: November 2004

A Weyl type of action which is scale free and quadratic in the curvature is suggested for strong gravity. The corresponding field equations have solutions which imply confinement. At the QCD scale, the scale invariance is broken inducing a Hilbert type term which describes the short distance behavior. This approach may provide a strong gravity basis for QCD.
GROUND STATE PERTURBATION OF N-ANYON IN A MAGNETIC FIELD
Authors: MYUNG YUN SOO , CHOI J.M. , UM M.J. , JUE C.
Published: November 2004

We study N-anyon of the α-statistics in a uniform magnetic field, to investigate certain properties of the ground state of a fractional statistics. Using the improved bosonic end-perturbation theory, we obtain the first order perturbative energy shift of the ground state energy. It is realized that there exists a second order perturbative energy with Landau levels.
SUSY AUXILIARY FIELDS FROM BRST ANALYSIS
Authors: BLAGOJEVIĆ M. , SAZDOVIĆ B. , VUKAŠINAC T.
Published: November 2004

A generalized Lagrangian BRST formalism is used to study globally supersymmetric systems with open classical gauge algebra. It is shown that in this approach one can naturally introduce a set of auxiliary fields, so that new form of the original theory has closed classical algebra.
QUANTUM PARTICLE ON A QUANTUM CIRCLE
Authors: BRZEZIŃSKI TOMASZ , REMBIELIŃSKI JAKUB , SMOLIŃSKI KORDIAN A.
Published: November 2004

We describe a q-deformed dynamical system corresponding to the quantum free particle moving along the circle. The algebra of the observables is constructed and discussed. We construct and classify irreducible representations of the system.
MORE ON PARASUPERSYMMETRIES OF THE SCHRÖDINGER EQUATION
Authors: BECKERS J. , DEBERGH N. , NIKITIN A.G.
Published: November 2004

One-dimensional spatial physical systems described by Schrödinger equations with time-independent interactions admit nth order parasupersymmetries. The general systems of differential equations for the parasupersymmetric operators are obtained and superposed with previous supersymmetric results. The interesting case of second order parasupersymmetries is completely solved.
COMMENTS ON W± AND Z0 DECAY TO π±0γ
Authors: HU JIAN-GUO , HUANG CHAO-SHANG
Published: November 2004

The decay rates of gauge bosons W±, Z0 to πγ are calculated in the large momentum transfer formalism. We find that they are much suppressed rather than large enough to be measurable.
BOUNDS ON LEPTON FLAVOR CHANGING CURRENTS AND THE SOLAR NEUTRINO PUZZLE: Bounds on Lepton Flavor Changing Currents
Authors: DEGL’INNOCENTI SCILLA , RICCI BARBARA
Published: November 2004

We present a phenomenological analysis of a lepton flavor changing current, considering the case of interactions among leptons which change the neutrino flavor and are diagonal in the charged lepton sector. In the case of νe↔νµ transition, we derive a bound on the vector coupling constant GV≤0.16 GF from experimental data on νµ−e scattering. For a transition νe↔νx, from (anti) νe−e scattering experiments and from the analysis of advanced stellar evolutionary phases, we find GV≤0.55 GF. We discuss the compatibility of these data with a possible explanation of the solar neutrino puzzle. We also analyze how the present bounds can be improved in future long baseline neutrino experiments and atmospheric neutrino detectors.
RADIAL PULSATION EIGENFREQUENCIES OF DIQUARK STARS
Authors: SAHU PRADIP K.
Published: November 2004

We calculate the general relativistic pulsation eigenfrequencies of a mixture of constituent-mass quarks and diquarks stars. First we compute an approximation equation of state for pure diquarks and mixture of diquarks and quarks states and use it to obtain the range of periods for fundamental mode (0.2–0.6 milliseconds) and for higher modes (≤0.1 milliseconds).
LONG DISTANCE BEHAVIOR OF THE FOUR-DIMENSIONAL NONLINEAR SIGMA MODEL WITH ANOMALY
Authors: BAAQUIE BELAL E. , RAJEEV S.G.
Published: November 2004

We study the low energy behavior of the four-dimensional nonlinear sigma model with anomaly using the 2+∊ expansion and renormalization group methods. It is shown that the theory has a non-trivial ir stable fixed point, in addition to the usual trivial fixed point. If pions happen to exist in the non-trivial phase, their propagator would scale at low energies with anomalous exponents.
SELF-DUALITY AND THE KdV HIERARCHY
Authors: DAS ASHOK , GALVĀO C.A.P.
Published: November 2004

We derive the entire KdV hierarchy as well as the recursion relations from the self-duality condition on gauge fields in four dimensions.
RECENT RESULTS FROM LEP
Authors: QUAST GÜNTER
Published: November 2004

Recent results from the four experiments ALEPH, DELPHI, L3 and OPAL at the large electron-positron collider, LEP, at CERN are reviewed. Analyzes from an integrated luminosity of about 20 pb −1 per experiment, taken at different center-of-mass energies within ±3 GeV around the Z0 resonance, are available now. Here, the main emphasis is put on the relevance of these measurements for precision tests of the Standard Model of the electroweak interaction.
DEFORMATION OF THE WAKIMOTO CONSTRUCTION
Authors: ABADA A. , BOUGOURZI A.H. , EL GRADECHI M.A.
Published: November 2004

We present the extension of the Wakimoto construction to the Uq( su (2)k) quantum current algebra and its associated Zk quantum parafermion algebra. This construction is achieved in terms of various deformations of three classical free boson fields. We also give the vertex operators corresponding to the quantum spin-j representation.
THE RENORMALIZATION OF THE NON-RENORMALIZABLE FOUR-DIMENSIONAL FOUR-FERMION INTERACTION
Authors: KRASNIKOV N.V.
Published: November 2004

We show that the non-renormalizable four-dimensional four-fermion Nambu interaction of color quarks can be renormalized. The non-renormalizable four-fermion interaction of color quarks is equivalent to the special (fixed-point) solution of the renormalization group equations for the renormalizable theory describing the interaction of the scalar fields with color quarks.
DYNAMICAL SUPERSYMMETRY AND SOLUTIONS FOR PAULI HAMILTONIANS
Authors: DEMERS JEAN-GUY
Published: November 2004

A charged point particle interacting with a vortex in 2+1 dimensions (or the relative coordinate of two anyons) possesses a dynamical so(2, 1) symmetry that can be exploited to solve for the case when an external harmonic oscillator potential is added. Moreover, if the particle carries spin 1/2, its interaction with the vortex exhibits a dynamical spl*(2, 1) supersymmetry, which can be imported to the cases where a harmonic oscillator or an external magnetic field is present. Using this supersymmetry, the corresponding Pauli Hamiltonians can be solved algebraically.
STOCHASTIC QUANTIZATION OF NAMBU-JONA-LASINIO MODEL
Authors: ITO MASATOSHI , KASE HIROMI , MORITA KATSUSADA
Published: November 2004

Stochastic quantizations of the Nambu-Jona-Lasinio model with and without the bare mass term are carried out. It is shown that, although the linear fermion Langevin equation is not chiral-invariant, one obtains the chiral-invariant effective potential in the equilibrium limit when the bare mass vanishes. Numerical solutions of the growing order parameter and two kinds of effective potentials, which take qualitatively different forms if the bare mass is nonvanishing, are presented.
PSEUDOCLASSICAL DESCRIPTION OF THE MASSIVE SPINNING PARTICLE IN d DIMENSIONS
Authors: PLYUSHCHAY M.S.
Published: November 2004

Through the dimensional reduction of the pseudoclassical Lagrangian for a massless (d+1)-dimensional spinning particle, the modified Lagrangian for a massive spin-1/2 particle in d dimensions is constructed, which turns out to be classically equivalent to the ordinary N=1 worldline supersymmetric Lagrangian. The quantization of the modified system in d=2n+1 is shown to lead, unlike the ordinary pseudoclassical model, exactly to the (2n+1)-dimensional Dirac equation, whereas in an even d=2n the two systems are also equivalent at the quantum level and describe the states, obeying the 2n-dimensional Dirac equation.
UNIFICATION OF GRAVITY, GAUGE AND HIGGS FIELDS BY CONFINED QUANTUM FIELDS II-EFFECTIVE THEORY
Authors: ISSE TOSHIKI
Published: November 2004

Dynamics of quantized free fields (of spin 0 and 1/2) contained in a subspace V* of an (N+4)-dimensional flat space V is studied. The space V* is considered as a neighborhood of a four-dimensional submanifold M arbitrarily embedded into V. We show that Einstein SO (N)-Yang-Mills Higgs theory is induced as a low energy effective theory of the system. Gravity, SO (N) gauge fields and Higgs fields are obtained from embedding functions of M.
A CUBIC DEFORMATION OF su(2)
Authors: DELBECQ C. , QUESNE C.
Published: November 2004

A two-parameter cubic algebra [Formula: see text] which goes into su(2) for p, q→1 and into Witten’s first deformation of su(2) for p→1, q≠1, is presented. In the carrier space of its representations, the J0 spectrum is exponential. In the special case where 0
 3.
SOLAR NEUTRINOS WITH EXOTIC SCATTERING
Authors: PULIDO JOÃO
Published: November 2004

The possibility of unconventional neutrino scattering in the Sun via flavor changing neutral currents as a possible source of the solar neutrino deficit is investigated. If the effect is really significant, a resonant process will occur. Taking into account the neutrino deficit reported by the solar neutrino experiments (Kamiokande II, SAGE Gallex), one finds Δ2m21 = (0.6–1.4) × 10−5 eV 2 with no vacuum mixing and 0.16 ≤ fex ≤ 0.34 where fex is the lepton violating coupling. Our understanding of the neutrino phenomenon in the Sun may be improved through accuracy improvements in experiments measuring νee− elastic scattering or others searching for exotic lepton decays.
PHOTON SUPPRESSION IN A BARYON-RICH PLASMA
Authors: DUMITRU A. , RISCHKE D. H. , STÖCKER H. , GREINER W.
Published: November 2004

We study photon production from quark-gluon plasmas with different baryo-chemical potentials µ B but fixed, given energy density ε. We find that the rate to lowest order O(ααs) decreases strongly with increasing µ B . Since to our knowledge µ B can be large in heavy-ion collisions, this result may be of importance concerning photon production as a signature for the creation of a quark-gluon plasma.
EDGE STATES IN 4D AND THEIR 3D GROUPS AND FIELDS
Authors: BALACHANDRAN A. P. , BIMONTE G. , TEOTONIO-SOBRINHO P.
Published: November 2004

It is known that the Lagrangian for the edge states of a Chern-Simons theory describes a coadjoint orbit of a Kac-Moody (KM) group with its associated Kirillov symplectic form and group representation. It can also be obtained from a chiral sector of a non-chiral field theory. We study the edge states of the Abelian BF system in four dimensions (4D) and show the following results in almost exact analogy: 1) The Lagrangian for these states is associated with a certain 2D generalization of the KM group. It describes a coadjoint orbit of this group as a Kirillov symplectic manifold and also the corresponding group representation. 2) It can be obtained from with a "self-dual" or "anti-self-dual" sector of a Lagrangian describing a massless scalar and a Maxwell field (the phrase "self-dual" here being used essentially in its sense in monopole theory). There are similar results for the non-Abelian BF system as well. These shared features of edge states in 3D and 4D suggest that the edge Lagrangians for BF systems are certain natural generalizations of field theory Lagrangians related to KM groups.
A METHOD FOR OBTAINING QUANTUM DOUBLES FROM THE YANG-BAXTER R-MATRICES
Authors: VLADIMIROV A. A.
Published: November 2004

We develop the approaches of Faddeev, Reshetikhin and Takhtajan1 and Majid2 which enable one to associate a quasitriangular Hopf algebra to every regular invertible constant solution of the quantum Yang-Baxter equations. We show that such a Hopf algebra is actually a quantum double.
MATRIX MODELS AND NON-PERTURBATIVE STRING PROPAGATION IN TWO-DIMENSIONAL BLACK HOLE BACKGROUNDS
Authors: DAS SUMIT R.
Published: November 2004

We identify a quantity in the c = 1 matrix model which describes the wave function for physical scattering of a tachyon from a black hole of the two-dimensional critical string theory. At the semiclassical level this quantity corresponds to the usual picture of a wave coming in from infinity, part of which enters the black hole becoming singular at the singularity, while the rest is scattered back to infinity, with nothing emerging from the white hole. We find, however, that the exact non-perturbative wave function is non-singular at the singularity and appears to end up in the asymptotic region "behind" the singularity.
GEOMETRY IN QUANTUM NON-INTEGRABILITY
Authors: ZHANG WEI-MIN , FENG DA HSUAN
Published: November 2004

We present a framework within which the way classical behavior emerges from arbitrary quantum dynamics can be studied systematically. This behavior is characterized by a quenching (topological) index Ξ, which controls the quenching of quantum correlations and signals the existence or the lack of classical limit. The compactness of geometry distinguishes two classes of quantum systems. The kick examples given in this letter suggest that quantum correlation suppresses chaos for compact geometry, while the opposite is found in the non-compact case.
DETECTION OF RELIC NEUTRINOS FROM THE DECAY OF FOURTH GENERATION NEUTRINOS USING THE NEUTRINO WINDOW ON THE EARTH
Authors: HONG WOO-PYO , CLINE DAVID B. , JUNG YOUNG-DAE
Published: November 2004

The recent precision measurements of Z0 decay width of LEP/SLC results may allow the existence of a heavy fourth generation neutrino with mass mν4 above ~45 GeV. The fourth generation neutrinos, by non-radiative decay in the early Universe, may yield a detectable diffuse relic neutrinos (νμ and ντ) on the earth with energies around 10–100 MeV. We discuss a possible detection method of the diffuse relic flux. This relic diffuse neutrino flux, if observed, would strongly support the existence of the fourth generation neutrinos.
SYMMETRY BREAKING BY WILSON LINES AND FINITE TEMPERATURE AND DENSITY EFFECTS
Authors: LEE CHUNG-CHIEH , HO CHOON-LIN
Published: November 2004

Effects of both finite temperature and density on Wilson line symmetry breaking mechanism is considered for an SU(N) theory defined on space-time manifold R1,d−2×S1 with massless fermion in the adjoint representation of the gauge group. Detailed analysis is given for the groups SU(2) and SU(3) on R1,2×S1. It is found that, at fixed fermion boundary condition, the critical temperatures and densities at which the full SU(N) symmetry is restored are the same for N=2 and N=3.
SINGULARITIES OF HADRONIC AMPLITUDES IN QUANTUM CHROMODYNAMICS
Authors: OEHME REINHARD
Published: November 2004

Singularities of hadronic amplitudes are discussed within the framework of QCD as formulated on the basis of the BRST algebra. Only non-perturbative QCD is considered. Local, composite fields are introduced for hadrons. Given confinement, it is shown that hadronic amplitudes have no thresholds or structure singularities (anomalous thresholds) which are directly related to the underlying quark-gluon structure. In contrast, general amplitudes of QCD must have singularities in channels with nonzero color quantum number, which can be related to unphysical states.
SUGAWARA-TYPE CONSTRUCTIONS FOR THE CLASSICAL WN ALGEBRA
Authors: KUPERSHMIDT B.A.
Published: November 2004

A number of different Sugawara-type constructions is described for the classical WN algebra. This number is M+1 for W2M and W2M+1.
THE NO-HAIR THEOREM FOR THE ABELIAN HIGGS MODEL
Authors: LAHIRI AMITABHA
Published: November 2004

We consider the general procedure for proving no-hair theorems for static, spherically symmetric black holes. We apply this method to the Abelian Higgs model and find a proof of the no-hair conjecture that circumvents the objections raised against the original proof due to Adler and Pearson.
PIONIC EFFECTS IN DEEP INELASTIC SCATTERING OFF NUCLEI
Authors: GONZÁLEZ P. , VENTO V.
Published: November 2004

The structure functions calculated in the chiral bag model reproduce quite well, after appropriate perturbative evolution to large energy scales, the experimental data. We use these results to interpret the structure of the EMC data as a quenching of the pion decay constant due to the in-medium behavior of the nucleon. This explanation supports recent proposals of this phenomenon whose origin is the scale invariance of the QCD Lagrangian.
SEMICLASSICAL APPROXIMATION FOR A CLASS OF QUANTUM p-BRANE MODELS
Authors: BYTSENKO ANDREI A. , ZERBINI SERGIO
Published: November 2004

A class of quantum p-brane models is considered. An action that is linear in the determinant of the world-metric and equivalent to Nambu-Goto-Dirac p-brane action is proposed. A semiclassical approximation to path integral quantization is presented for the bosonic sector when the closed p-brane sweeps out an n=(p+1) dimensional compact hyperbolic manifold Hn/Γ, Γ being a strictly hyperbolic subgroup of isometries of the Lobachevsky space Hn. The computation of the related Laplace operator determinant is presented.
YANG-BAXTER EQUATION FOR BROKEN $\mathbb{Z}_N^{\otimes n-1}$ MODELS
Authors: QUANO YAS-HIRO , FUJII AKIRA
Published: November 2004

We construct a factorized representation of the [Formula: see text]-Sklyanin algebra from the vertex-face correspondence. Using this representation, we obtain a new solvable model which gives an [Formula: see text]-generalization of the broken ℤN model. We further prove the Yang-Baxter equation for this model.
THE K+→π+π0γ(DE) DECAY IN CHIRAL PERTURBATION THEORY AT THE QUARK LEVEL
Authors: IVANOV A.N. , NAGY M. , TROITSKAYA N.I.
Published: November 2004

The probability of the K+→π+π0γ (DE) decay with the direct emission of a photon is calculated. The strong low-energy interactions are accounted for within chiral perturbation theory at the quark level, based on the Extended Nambu-Jona-Lasinio (ENJL) model approximating QCD at low energies. The dominant role of chiral anomalies is confirmed.
DENSE (2+1)-DIMENSIONAL QUANTUM ELECTRODYNAMICS IN A UNIFORM MAGNETIC FIELD
Authors: ZEITLIN VAD. YU.
Published: November 2004

The effective action of the dense QED 2+1 in a uniform magnetic field is calculated. It is shown that the condition of the electrical neutrality [Formula: see text] is satisfied at µ≠0 and that in the neutral QED 2+1 Meissner effect takes place.
ARE QUARKS AND LEPTONS RELATED BY C, P AND T SYMMETRIES?
Authors: FOOT R. , LEW H. , VOLKAS R.R.
Published: November 2004

It is possible that the similarities between the quarks and leptons arise from the spontaneous breaking of an exact quark-lepton Z2 discrete symmetry. We study the connection between this type of discrete symmetry and the discrete symmetries of charge conjugation, parity and time reversal: C, P and T.
A COMMENT ON THE HAMILTON FORMALISM FOR NONLINEAR INTEGRABLE MODELS
Authors: KAWAI EI-ICHIRO
Published: November 2004

It is clarified that by taking dual symplectic structures into account in an infinite-dimensional phase manifold, at least one of which must be nonlinear, induces a completely unique nonlinear integrable model.
ON THE POSSIBILITY OF SPINORIAL QUANTIZATION IN THE SKYRME MODEL
Authors: GIULINI DOMENICO
Published: November 2004

We consider the configuration space of the Skyrme model and give a simple proof that loops generated by 2π-rotations are contractible in the even-, and non-contractible in the odd-winding-number sectors.
SEMICLASSICAL EXPANSION FOR DIRAC HAMILTONIANS
Authors: ARRIOLA E. RUIZ , SALCEDO L.L.
Published: November 2004

A simple and efficient calculation of the level density of Dirac Hamiltonians in the semi-classical approximation is presented. The method is applied to compute the level density up to ħ4-order of a Dirac Hamiltonian with time independent scalar and electromagnetic external fields. The final expressions are explicitly gauge invariant and convergent at the turning points. As a byproduct, we obtain ħ-corrections to the semiclassical quantization rule of a Dirac Hamiltonian in D space dimensions. The result is illustrated in an exactly solvable problem.
THE BATEMAN SOLUTIONS OF THE SPINOR WAVE EQUATION
Authors: HILLION PIERRE
Published: November 2004

Many years ago Bateman1,2 gave two methods for generating new solutions of the scalar wave equation from a particular one. We generalize these two methods to the spinor wave equation.
NAMBU-JONA-LASINIO MODEL IN CURVED SPACE-TIME
Authors: INAGAKI T. , MUTA T. , ODINTSOV S.D.
Published: November 2004

The phase structure of Nambu-Jona-Lasinio model with N-component fermions in curved space-time is studied in the leading order of the 1/N expansion. The effective potential for composite operator [Formula: see text] is calculated by using the normal coordinate expansion in the Schwinger proper-time method. The existence of the first order phase transition caused by the change of the space-time curvature is confirmed and the dynamical mass of the fermion is calculated as a simultaneous function of the curvature and the four-fermion coupling constant. The phase diagram in the curvature and the coupling constant is obtained.
THE SPECTRUM OF TOPOLOGICALLY MASSIVE QUANTUM ELECTRODYNAMICS
Authors: DOBROLIUBOV MIKHAIL I. , ELIEZER DAVID , KOGAN IAN I. , SEMENOFF GORDON W. , SZABO RICHARD J.
Published: November 2004

We discuss the possibility for the spectrum of topologically massive quantum electrodynamics with spinor matter fields to contain unexpected and unusual stable particle excitations for certain values of the topological photon mass. The new field theoretical phenomena arising from this novel spectral structure are briefly discussed.
GAUGE INDEPENDENT PHASE STRUCTURE OF GAUGED NAMBU-JONA-LASINIO AND YUKAWA MODELS
Authors: KONDO KEI-ICHI
Published: November 2004

We investigate the critical behavior of the gauged NJL model (QED plus four-fermion interaction) and the gauged Yukawa model by the use of the inversion method. By calculating the gauge-invariant chiral condensate in the inversion method to the lowest order, we derive the critical line which separates the spontaneous chiral-symmetry breaking phase from the chiral symmetric one. The critical exponent for the chiral order parameter associated with the second order chiral phase transition is shown to take the mean field value together with possible logarithmic correction to the mean-field prediction. All the above results are gauge-parameter independent and are compared with the previous results obtained from the Schwinger-Dyson equation for the fermion propagator.
EQUIVALENCE OF S3-INVARIANT LATTICE MODEL AND MODEL OF VERTEX-FACE TYPE
Authors: BOOS H.E.
Published: November 2004

We show that the S3-invariant model proposed in Ref. 2 is equivalent to vertex-face model with two kinds of Boltzmann weights, which appeared to satisfy the generalized Yang-Baxter equation. The more general solution of this equation is constructed in the framework of some appropriate ansatz. This solution depends on the continuous parameter q. The initial model is a particular case of q=±ie∓2π/3i. The integrability of this model is discussed.
LIGHT-CONE QUANTIZATION OF SCALAR FIELD
Authors: CHAO LIU
Published: November 2004

The light-cone quantization of two-dimensional one-component self-interacting scalar field theory is discussed using the Dirac method. Several subtleties are pointed out. In particular, it is found that the left and right quantization are not essentially equivalent, at least for the free field case, and that there is a Virasoro current algebra for every non-trivially self-interacting field theories which show that all the nonconformally interacting two-dimensional field theory can be considered as the off-critical perturbation of conformal field theories.
THE c=1 MATRIX MODEL FORMULATION OF TWO-DIMENSIONAL YANG-MILLS THEORIES
Authors: PANZERI STEFANO
Published: November 2004

We find the exact matrix model description of two-dimensional Yang-Mills theories on a cylinder or on a torus and with an arbitrary semisimple compact gauge group. This matrix model is the singlet sector of a c=1 matrix model where the matrix field is in the fundamental representation of the gauge group. We also prove that the basic constituents of the theory are Sutherland fermions in the zero coupling limit, and this leads to an interesting connection between two-dimensional gauge theories and one-dimensional integrable systems. In particular we derive for all the classical groups the exact grand canonical partition function of the free fermion system corresponding to a two-dimensional gauge theory on a torus.
IS THE ANOMALOUS BEHAVIOR OF THE POMERON SPIN-FLIP PART POSSIBLE IN PERTURBATIVE QCD?
Authors: GOLOSKOKOV S.V.
Published: November 2004

The pomeron spin-flip properties at small quark masses and momenta transfer in the [Formula: see text] order of perturbative QCD are analyzed. It is shown that the mass and the momentum-transfer singularities exist in the axial and mass terms of the gluon-ladder diagrams for quarks on the mass shell and they are absent in the total spin-flip amplitudes of qq and γq scattering.
DECAY RATE OF A POSITRONIUM: REVIEW OF THEORY AND EXPERIMENT
Authors: DVOEGLAZOV VALERI V. , FAUSTOV RUDOLF N. , TYUKHTYAEV YURI N.
Published: November 2004

The present status of theoretical and experimental investigations of the decay rate of a positronium is considered. The increasing interest to this problem has been caused by the disagreement of the calculated value of Γ3 (o−Ps) and the recent series of precise experiments. The necessity of new calculations on the basis of the quantum field methods in bound state theory, taking into account the dependence of the interaction kernel on relative energies, is pointed out.
GENERALIZED COVARIANT TWO-BODY WAVE EQUATION
Authors: SOMMERER ALAN J. , SPENCE JOHN R. , VARY JAMES P.
Published: November 2004

We show that the traditional quasipotential equations (QPEs) may be viewed as special cases of a more general QPE written in terms of three parameters. We analyze the behavior of the ladder QPEs for bound states in terms of these parameters. From the generalized QPE we obtain one QPE that resembles more closely to QED fourth order perturbative results than the traditional QPEs. We compare and contrast the QPEs in the low, intermediate, and large coupling regimes, including fits to heavy meson spectra.
PHASE STRUCTURE OF COMPACT LATTICE QED3 WITH MASSLESS FERMIONS
Authors: AZCOITI VICENTE , LUO XIANG-QIAN
Published: November 2004

In the framework of (2+1)-dimensional compact lattice QED with light fermions, we investigate the phase diagram in the (β, N) plane. The approximations involved are related to an expansion of the effective fermionic action as a power series of the flavor number N. We also develop a new mechanism for understanding the N-critical phenomenon in the full theory. Our results for the specific heat show the existence of a first order phase transition line at large-N, terminating in a critical point at finite β. We give strong evidences that this qualitative result should not be changed with the inclusion of higher order terms in the N expansion.
SUPERCONFORMAL STRUCTURES AND HOLOMORPHIC 1/2-SUPERDIFFERENTIALS ON N=1 SUPER RIEMANN SURFACES
Authors: KACHKACHI H. , KACHKACHI M.
Published: November 2004

Using the super Riemann-Roch theorem we give a local expression for a holomorphic ½-superdifferential in a superconformal structure parametrized by special isothermal coordinates on an N=1 super Riemann surface. The holomorphy of these coordinates with respect to super Beltrami differentials is proved. The monodromy of these differentials is discussed.
VORTICES IN CURVED SPACE-TIME
Authors: EDELSTEIN J.D. , LOZANO G. , SCHAPOSNIK F.A.
Published: November 2004

We study an Abelian Higgs model coupled to a background metric. We find Bogomol’nyi equations when the coupling is achieved through an Rɸ2 term (R being the scalar curvature and ɸ the Higgs scalar). Remarkably, these equations coincide with those arising in models where the gauge field dynamics is governed by a Chern-Simons term so that vortex solutions in our system can be related to self-dual Chern-Simons vortices.
ON THE BEHAVIOR OF DYNAMICAL QUARK-ANTIQUARK PAIRS IN EXTERNAL CHROMO-ELECTRIC FIELDS
Authors: IVANOV A. N. , TROITSKAYA N. I. , FABER M. , SCHALER M. , NAGY M.
Published: November 2004

The vacuum structure of QCD in an external chromo-electric field is investigated within the continuum space-time formulation of perturbative QCD and the extended NambuJona-Lasinio model, used as a low-energy approximation of QCD. We show that the density of dynamical quark-antiquark pairs decreases with increasing external chromoelectric field strength. These results are compared with recent numerical simulations of lattice QCD which indicate restoration of chiral symmetry in the vicinity of a static color
PRODUCTION OF Q-BOSONS BY A CLASSICAL CURRENT: AN EXACTLY SOLVABLE MODEL
Authors: GRANOVSKII YA. I. , ZHEDANOV A. S.
Published: November 2004

An exactly solvable model of q-bosons interacting with classical current is considered. The main important physical properties of this model are investigated: non-Poisson distribution of q-bosons, q-Bose condensation, finite number of discrete energy levels etc. Most profound effect of the model is the destroying of a vacuum state under strong current.
NEUTRINO ELECTRON SCATTERING
Authors: RÄDEL GABY , BEYER ROLF
Published: November 2004

This article reviews experimental results obtained from studies of neutrino electron scattering and shows in particular the important input from these experiments to the improved knowledge of weak neutral currents and the confirmation of the Standard Model at tree level. Special emphasis is put on recent high precision νe-experiments, whose results on electroweak parameters allow, in combination with precise results obtained at higher Q2, a test of the Standard Model at the level of higher order corrections.
PROTON HELICITY FLOW TO MESONIC CLOUD AND AXIAL COUPLINGS OF BARYONS
Authors: ZOLLER V. R.
Published: November 2004

We apply the relativistic light-cone perturbation theory to a flow of the helicity of baryons to the angular momentum of the mesonic cloud. Starting with the SU(6) symmetry, we find good description of the axial couplings in β-decay of hyperons. In the light-cone technique, the pattern of the spin-flip of nucleons differs significantly from that expected in the conventional non-relativistic models.
A LARGE CLASS OF SPACE-TIMES FROM THE SL(2, ℝ)/U(1) COSET MODEL
Authors: MOHAMMEDI NOUREDDINE
Published: November 2004

We show that the gauged SL (2, ℝ) WZWN model yields a large class of space-times in two dimensions. The c = 1 matter coupled to gravity and the black hole singularity are just two particular cases in these space-times.
A FINITE TEMPERATURE PERIODIC STRUCTURE IN (SUPER)STRING THEORY
Authors: BYTSENKO A. A. , ELIZALDE E. , ODINTSOV S. D. , ZERBINI S.
Published: November 2004

Using a Laurent series representation for the (super)string one-loop free energy, an explicit form for the analytic continuation of the Laurent series beyond the critical (Hagedorn) temperature is obtained. As an additional result, a periodic structure in (super)string thermodynamics is found. A brief physical discussion about the origin and meaning of such a structure is carried out.
CURRENT-CURRENT CORRELATION FUNCTION ON ALGEBRAIC CURVES
Authors: SOBCZYK JAN
Published: November 2004

We derive an explicit expression for a current-current correlation function on a Riemann surface represented as 3 sheets ramified covering over CP(1). The method used in the paper can be easily applied to more general algebraic curves. Knowledge of G(z, w) enables calculation of the expectation value of the energy momentum tensor for scalar field.
MASSIVE DIRAC NEUTRINOS AND SN1987A
Authors: RAJPOOT SUBHASH
Published: November 2004

If neutrinos are massive Dirac particles, their right-handed components are inert to interactions with matter. However, the helicity flip mechanism due to the mass term can participate in the cooling of a new born star. The observed neutrino bursts from SN1987A constrained Dirac neutrino masses to lie between 1 keV and 10 keV so as to avoid rapid cooling due to the mass induced helicity flip mechanism. We suggest scalar particle mediated new interactions between the right-handed neutrinos and nuclear matter that trap the right-handed neutrinos long enough so that the total energy of the exploding star is carried away predominantly by left-handed neutrinos. The bounds from cosmology are also shown to be satisfied.
SOFT PHOTON RADIATION IN $e^+ e^- \to t\bar t\to b\bar bW^+ W^-$
Authors: ABU LEIL G. F.
Published: November 2004

We present a detailed analysis of soft photon radiation in [Formula: see text]. The radiation pattern is shown to depend sensitively on the top mass, width and energy, as well as the relative orientation of the initial and final state particles. Optimum conditions in which initial state radiation is minimized and the radiation pattern has the richest structure are discussed.
Q-DEFORMATION OF VIRASORO ALGEBRA AND LATTICE CONFORMAL THEORIES
Authors: BELOV ALEXANDER A. , CHALTIKIAN KAREN D.
Published: November 2004

A natural definition of q-deformation of Virasoro and superconformal algebras is proposed. New Lie algebraic symmetries are shown to describe the lattice version of the original theory. On the classical (Poisson brackets) level these two-loop algebras are shown to be isomorphic to the Faddeev-Takhtadjan-Volkov lattice Virasoro algebra.