bluuebunny/crossref_metadata_2025 huggingface dataset:
STUDY OF HYDROGEN-LIKE MESON STATES WITH A SCREENED POTENTIAL MODEL
Authors: DONG YU-BING
Published: November 2004

By utilizing the screened potential model, the spectra and decay properties of hydrogen-like mesons [Formula: see text] are studied. The calculated ratio of M1 decay widths for the D*+ and D*0 mesons is 0.0286. This result is much smaller than the data of MARK3 in 1988, but agrees with the observed data of CLEO in 1992. The result indicates that the contradiction between the calculated result and the data of MARK3 for hydrogen-like mesons in the quark model can be understood, if future experiment can confirm the data of CLEO in 1992.
TOWARDS A COMPLETE TWISTORIZATION OF THE HETEROTIC STRING
Authors: BANDOS IGOR A. , VOLKOV DMITRIJ V. , CEDERWALL MARTIN , SOROKIN DMITRIJ P.
Published: November 2004

In D = 3, 4, 6 and 10 space-time dimensions considered is a string model invariant under transformations of N = 1 space-time supersymmetry and n = D − 2 local worldsheet supersymmetry with both the Virasoro constraints solved in the twistor form. The twistor solution survives in a modified form even in the presence of the heterotic fermions.
D = 2 STRING THEORY IN TARGET SPACE/WORLDSHEET LIGHT-CONE GAUGE
Authors: ZUBAREV A. P.
Published: November 2004

The D = 2 free string in the linear dilaton background is considered in the so-called target space/worldsheet light-cone gauge X+ = 0, g++ = 0, g+− = 1. After gauge-fixing, the theory has the residual Virasoro and U(1) current symmetries. The physical spectrum related to the SL 2-invariant vacuum is found to be trivial. We find that the theory has a non-trivial spectrum if the states in different nonequivalent representations ("pictures") of CFT algebra of matter fields are considered.
QUANTUM MECHANICS AS QUANTUM MEASURE THEORY
Authors: SORKIN RAFAEL D.
Published: November 2004

The additivity of classical probabilities is only the first in a hierarchy of possible sum rules, each of which implies its successor. The first and most restrictive sum rule of the hierarchy yields measure theory in the Kolmogorov sense, which is appropriate physically for the description of stochastic processes such as Brownian motion. The next weaker sum rule defines a generalized measure theory which includes quantum mechanics as a special case. The fact that quantum probabilities can be expressed "as the squares of quantum amplitudes" is thus derived in a natural manner, and a series of natural generalizations of the quantum formalism is delineated. Conversely, the mathematical sense in which classical physics is a special case of quantum physics is clarified. The present paper presents these relationships in the context of a "realistic" interpretation of quantum mechanics.
COMPLEX LINE BUNDLES OVER TWO-SPHERE AND BLACK HOLE PHYSICS
Authors: GONCHAROV YU. P. , YAREVSKAYA J.V.
Published: November 2004

We discuss a long-standing problem of the global topological non-trivial properties of the four-dimensional space-times underlying black hole physics and observe that the standard space-time topology of the ℝ2×S2 form for black hole physics admits topologically inequivalent configurations of a complex scalar field on black hole by virtue of the availability of non-trivial complex line bundles over S2. Each configuration can be labeled by its Chern number n∈ℤ. For the Schwarzschild black hole we formulate an appropriate wave equation for these configurations in massless case and describe its solutions as a first step to study quantum effects for the above configurations within the framework of black hole physics.
N=2 SUPERSTRING THEORY GENERATES SUPERSYMMETRIC CHERN-SIMONS THEORIES
Authors: NISHINO HITOSHI
Published: November 2004

We show that the action of self-dual supersymmetric Yang-Mills theory in four dimensions, which describes the consistent massless background fields for N=2 superstring, generates the actions for N=1 and N=2 supersymmetric non-Abelian Chern-Simons theories in three dimensions after some dimensional reductions. Since the latters play important roles for supersymmetric integrable models, this result indicates the fundamental significance of the N=2 superstring theory controlling (possibly all) supersymmetric integrable models in lower dimensions.
A NEW SET OF TWO-PARAMETER SOLUTIONS OF THE YANG-BAXTER EQUATION
Authors: CISŁO JERZY
Published: November 2004

The connection between Zn×Zn symmetric solutions of the star-triangle equation and solutions of the Yang-Baxter equation is used to construct a new set of n-state (for any odd n) two-parameter solution of the Yang-Baxter equation. For n=3 the solution was found by M. Jimbo and T. Miwa in 1985.
ON q-COHERENT STATE OF q-DEFORMED OSCILLATOR
Authors: YANG YAPING , YU ZURONG
Published: November 2004

In this letter, we discuss detailed properties of coherent state of deformed oscillator, and obtain some significant results.
ON THE SINGULAR BEHAVIOR OF STRUCTURE FUNCTIONS AT LOW x
Authors: NAVELET H. , PESCHANSKI R. , WALLON S.
Published: November 2004

We discuss the phenomenological extraction of the leading j-plane singularity from singlet structure functions Fs estimated at small x. Using a saddle point method we show that [Formula: see text] is a suitable observable for this purpose in the region x≤10−2. As an application, we confront and distinguish in a model-independent way structure function parametrizations coming from two different QCD evolution equations, namely the Lipatov (or BFKL) equation and the Gribov-Lipatov-Altarelli-Parisi (or GLAP) equation. Recent results on the proton structure function F2 at HERA are discussed in this framework.
VERTEX FUNCTIONS FOR HIGHER ORDER FIELD THEORIES
Authors: BOLLINI C.G. , OXMAN L.E. , ROCCA M.
Published: November 2004

For higher order theories, the propagators are characterized by a set of complex poles and a complex line of integration on the energy plane. A closed loop in a Feynman diagram implies an integration on an integral energy variable. The resultant composition of general propagators is explicitly obtained for triangle diagrams. We also give the method for the evaluation of arbitrary polygons.
ELECTROMAGNETIC-GRAVITATIONAL CONVERSION CROSS-SECTIONS IN EXTERNAL ELECTROMAGNETIC FIELDS
Authors: LONG HOANG NGOC , SOA DANG VAN , TRAN TUAN A.
Published: November 2004

The classical processes: the conversion of photons into gravitons in the static electromagnetic fields are considered by using Feynman perturbation techniques. The differential cross-sections are presented for the conversion in the electric field of the flat condenser and the magnetic field of the solenoid. A numerical evaluation shows that the cross-sections may have the observable value in the present technical scenario.
ON THE FOCK SPACE REPRESENTATION OF THE WITTEN VERTEX
Authors: DICK RAINER
Published: November 2004

The bosonic overlap conditions for operator representations of the Witten vertex and its closed string analog are solved in closed form for arbitrary many external strings. This is accomplished by the use of transformed operator bases of the strings. In particular, the bosonic factor of the Witten vertex for three closed strings is realized in Fock space.
THE SU(2) GLOBAL ANOMALY THROUGH LEVEL CIRCLING
Authors: AXENIDES MINOS , NIELSEN HOLGER BECH , JOHANSEN ANDREI
Published: November 2004

We discuss a novel manifestation of the SU(2) global anomaly in an SU(2) gauge theorywith an odd number of chiral quark doublets and arbitrary Yukawa couplings. We arguethat the massive four-dimensional Euclidean Dirac operator is non-Hermitian with itsspectrum of eigenvalues (λ, −λ) lying in pairs in the complex plane. Consequently theexistence of an odd number of normalizable zero modes of the four-dimensional massiveDirac operator is equivalent to a fermionic level exchange phenomenon, level “circling,”under continuous topologically non-trivial deformations of the external gauge field. Moregenerally global anomalies are a manifestation of fermionic level “circling” in any SP(2n)gauge theory with an odd number of massive fermions in the spinor representation andarbitrary Yukawa couplings.
BOSONIZATION OF A TOPOLOGICAL COSET MODEL AND NON-CRITICAL STRING THEORY
Authors: OHTA NOBUYOSHI , SUZUKI HISAO
Published: November 2004

We analyze the relation between a topological coset model based on super SL(2, R)/U(1) coset and non-critical string theory by using free field realization. We show that the twisted N=2 algebra of the coset model can be naturally transformed into that of non-critical string. The screening operators of the coset models can be identified either with those of the minimal matters or with the cosmological constant operator. We also find that another screening operator, which is intrinsic in our approach, becomes the BRST non-trivial state of ghost number 0 (generator of the ground ring for c=1 gravity).

The relation between non-critical strings and topological field theories is the subject of current interest. It has long been suggested that the latter theories describe the unbroken phase of gravity,1 but their precise relation has not been clear.

It has been known that the twisting of N=2 superconformal field theory gives rise to topological theory.1,2 This suggests that any non-critical string theories may have hidden N=2 superconformal symmetry. Indeed, several authors have observed that the BRST current and the antighost field b(z) generate an algebra that is quite similar but apparently not identical to the N=2 superconformal algebra.3 It turns out that the BRST current can be modified by total derivative terms so that the antighost and the physical BRST current exactly generate a topologically twisted N=2 superconformal algebra.4,5 This does not identify, however, the structure of the models with N=2 symmetry.

Recently, rather non-trivial correspondence between super SL(2, R)k/U(1) coset model6 and c=1 string has been analyzed through twisted N=2 structure. Mukhi and Vafa7 have revealed an amazing correspondence between these two models for k=3. In this letter, we discuss the relation of these models and the generalization of the correspondence to the minimal models coupled to gravity by means of the free field realization. We find that there is another interesting correspondence for k=1.

Super SL(2, R)k/U(1) model is described by the bosonic coset model of SL(2, R)k×U(1)/U(1).8 For a representation of SL(2, R)k, we use the following
TRIANGULAR ALPHA CLUSTER GEOMETRIES AND HARMONIC OSCILLATOR SHELL STRUCTURE
Authors: RAE W.D.M. , ZHANG J.
Published: November 2004

We demonstrate that there is a link between the underlying geometrical structure in the Bloch-Brink α-cluster model and shell structure in the axially-symmetric deformed Harmonic oscillator model. Indeed all the axially-symmetric Harmonic oscillator configurations can be related to structures formed from triangular layers of α-clusters whose centres lie on an fcc lattice. In particular all Harmonic oscillator closed-shell nuclei can be related to tetrahedral arrangements of α-cluster centers, generalizing the result known for 16O for many years. These results suggest that the octupole degree of freedom which can be associated with triangular and tetrahedral α-cluster structures could be important in such nuclei.
THE g-LOOP VACUUM IN THE NEVEU-SCHWARZ SECTOR BY OPERATOR SEWING OF DUAL VERTICES
Authors: ENGBERG NICLAS
Published: November 2004

The matter part of the g-loop Reggeon vacuum of the Neveu-Schwara string is constructed by operator sewing of dual four-vertices using superfields. The economical parametrization of the locations of the external legs in the dual vertex leads to significant simplifications compared to ordinary sewing of three vertices. The final answer is in agreement with previous results, derived both through a mixture of path-integrals and sewing of three vertices, and through supersymmetrization of the bosonic result.
PERTURBATIVE GAUGE ANOMALIES IN THE HAMILTONIAN FORMALISM: A COHOMOLOGICAL ANALYSIS
Authors: BARNICH G.
Published: November 2004

The quantum action principle of renormalization theory is applied to the antibracket-antifield formalism for Hamiltonian systems. General results on the local BRST cohomology allow one to prove that the anomalies appear in the time development of the BRST charge and violate the nilpotency of this charge. Furthermore they are equivalent to those of the Lagrangian formalism. The analysis provides a completely gauge and regularization independent proof of Faddeev’s conjecture on the relationship between gauge anomalies and Schwinger terms in the context of descent equations.
ON PROBLEM OF ANOMALIES IN DUAL VERSION OF 10D SUPERGRAVITY IN SUPERSPACE
Authors: TERENTJEV M.V.
Published: November 2004

The dual version of 10D supergravity (SUGRA) is analyzed in the superspace approach. The standard set of constraints on the fundamental superfields is used, making it possible to consider the theory on the mass shell. There is an additional degree of freedom in the theory that consists in the presence of the 3-form superfield Zabc, which is not determined by the equations of motion for fundamental fields. The Z field is the ghost-free and is restricted by linear homogeneous equations. The derivation of these equations is the main result of the present paper. The Z field describes the Green-Schwarz anomaly compensating terms in dual SUGRA.
GAUGE INVARIANCE AND QUANTIZATION OF THE SPINOR STRONG INTERACTION MODEL
Authors: HOH F.C.
Published: November 2004

The spinor strong interaction model recently proposed to account for the meson spectra is extended to include interaction with external gauge fields. An action integral is constructed and a restricted variational principle is employed to reproduce the earlier basic meson equations.

In establishing U(1) gauge invariance, the so-called U(1) problem, the absence of pseudoscalar singlet mesons that do not decay strongly, is naturally resolved. SU(2)× U(1) or SO(3) gauge invariance leads to that pseudoscalar isodoublet or isotriplet mesons can generate masses of the gauge bosons without recourse to the unobserved Higgs bosons of the standard electroweak model. The gauge boson masses relate to the linear confinement potential constant of pseudoscalar mesons.

The spinor strong interaction model is quantized in a macroscopic approximation due to the finite size of mesons. Commutation relations and the rest frame Hamiltonian are obtained. In this frame, the relative energy of the quark and antiquark is shown to vanish.
ELECTROMAGNETIC DEFLECTION OF SPINNING PARTICLES
Authors: COSTELLA JOHN P. , MCKELLAR BRUCE H.J.
Published: November 2004

We show that it is possible to obtain self-consistent and physically acceptable relativistic classical equations of motion for a pointlike spin-half particle possessing an electric charge and a magnetic dipole moment, directly from a manifestly covariant Lagrangian, if the classical degrees of freedom are appropriately chosen. It is shown that the equations obtained encompass the well-tested Lorentz force and Thomas-Bargmann-Michel-Telegdi spin equations, as well as providing a definite specification of the classical magnetic dipole force, whose exact form has been the subject of recent debate. Radiation reaction — the force and torque on an accelerated particle due to its self-interaction — is neglected at this stage.
A SEMIPHENOMENOLOGICAL DETERMINATION OF QUARK CONDENSATE
Authors: GUO XIN-HENG , HUANG TAO
Published: November 2004

A consistent equation for the quark condensate in the chiral limit provides a determination of the renormalization-group-invariant quark condensate. A critical point at which the strong coupling constant is big enough for chiral symmetry breaking to take place is found. They are analyzed at the one- and two-loop levels respectively. An intuitive picture of the condensation above the critical coupling constant is discussed.
NEW PROPOSALS FOR THE REACTION e+e−→π+π−π0
Authors: ACHASOV N.N. , KOZHEVNIKOV A.A.
Published: November 2004

The influence of the singularity of the triangle diagram on patterns of ρω interference in the π+π− mass spectrum of the reaction e+e−→π+π−π0 is considered at energies in the range [Formula: see text]. This influence arises due to the difference between the phases of the ω→ρπ and ρ→ωπ transition amplitudes implied by the imaginary part of this diagram. The decay kinematics of the triangle diagram results in the distortion of the π+π− mass spectrum. Taking this diagram into account at energies in between ω and φ peaks implies the measurable decrease of the cross section. Experimental studies of the effect of the imaginary part of the triangle diagram at e+e− colliders with the luminosity L=1031 cm −2 s −1 or higher could be of great interest as a tool for testing the self-consistency of calculations going beyond the tree approximation and as the possibility of obtaining additional information on the mechanism of breaking of the OZI rule and G parity.
FUSION AND THE NEVEU-SCHWARZ SINGULAR VECTORS
Authors: BENOIT LOUIS , SAINT-AUBIN YVAN
Published: November 2004

Bauer, di Francesco, Itzykson and Zuber recently proposed an algorithm to construct all singular vectors of the Virasoro algebra. It is based on the decoupling of (already known) singular fields in the fusion process. We show the extension of their algorithm to the Neveu-Schwarz superalgebra.
COMPUTATION OF CRITICAL EXPONENT η AT O(1/N3) IN THE FOUR-FERMI MODEL IN ARBITRARY DIMENSIONS
Authors: GRACEY J.A.
Published: November 2004

We solve the conformal bootstrap equations of the four-fermi model or O(N) Gross-Neveu model to deduce the fermion anomalous dimension of the theory at O(1/N3) in arbitrary dimensions.
WZW-TODA REDUCTION USING THE CASIMIR OPERATOR
Authors: JACK I. , PANVEL J.
Published: November 2004

We construct a quantum Hamiltonian operator for the Wess-Zumino-Witten (WZW) model in terms of the Casimir operator. This facilitates the discussion of the reduction of the WZW model to the Toda field theory at the quantum level and provides a very straightforward derivation of the quantum central charge for the Toda field theory.
NONPERTURBATIVE QUARK PROPAGATOR APPROACH TO QCD AT LARGE DISTANCES
Authors: GOGOHIA V. SH.
Published: November 2004

A nonperturbative approach to QCD at large distances in the context of the Schwinger-Dyson equations and corresponding Slavnov-Taylor identity in the quark sector is presented. Making only one widely accepted assumption that the full gluon propagator becomes an infrared singular like (q2)−2 in the arbitrary covariant gauge, we find three and only three confinement-type solutions for the quark propagator (quark confinement theorem). Two of them vanish after the removal of the infrared regulation parameter. The third solution does not depend on this latter parameter, but it has no pole and it implies dynamical chiral symmetry breakdown (DCSB), which means a close connection between quark confinement and DCSB. We also show that multiplication solely by the quark infrared renormalization constant would make all the Green’s functions infrared finite (multiplicative renormalizability). The final forms of the renormalized (infrared finite) quark SD equations do not explicitly depend on a gauge-fixing parameter (“gauge invariance”). Our approach is free of ghost complications despite the fact that they play an essential role in nonperturbative dynamics. Our approach also implies the existence of a characteristic scale at which confinement, DCSB and other nonperturbative effects become essential. We solve explicitly the SD equation with corresponding ST identity for the above-mentioned IR finite quark propagator in the chiral limit and apply an effective potential in order to determine completely this solution.
WARD IDENTITIES AND W CONSTRAINTS IN THE GENERALIZED KONTSEVICH MODEL
Authors: MIKHAILOV A
Published: November 2004

The connection is obtained between Ward identities and W constraints in the generalized Kontsevich model with the potential X4/4. We show that Ward identities include W constraints (and do not include any other constraints) for this potential and make some observations in favor of the same connection for the model with the potential of the form X(K+1)/(K+1) for any K ≥ 2.
REALISTIC SIMULATION OF NJL MECHANISM WITH VECTOR-TYPE COUPLING
Authors: MITRA A. N. , MITRA-SODERMARK BANI
Published: November 2004

The concrete possibilities for a realistic simulation of the Nambu–Jona-Lasino mechanism of dynamical mass generation are examined from the viewpoint of a vector-type confining form of four-fermion Lagrangian with a natural mass scale which substitutes for the canonical NJL model of contact interaction, and is designed to keep a conscious link with spectroscopy. Such Lagrangians are known to lead (through the minimality condition on the effective action) to both the Schwinger–Dyson and Bethe–Salpeter equations for the quark-mass operator Σ(p) and the hadron-quark vertex function ΓH(q, P) respectively. With a choice of the interaction which corresponds to a Lorentz-covariant generalization of the familiar instantaneous approximation, the related Bethe–Salpeter equation already provides a good description of both [Formula: see text] and qqq spectra, as well a Lorentz-covariant access to different types of transition amplitudes via quark loops, within a common dynamical framework. With this precalibration, the model is subjected to the interlinked SDE and BSE for testing some key aspects of the NJL self-consistency mechanism by evaluating some basic constants. The results are: m NJL = 300 MeV , [Formula: see text]; Mσ = 857 MeV ; [Formula: see text]. From these values two independent estimates of mc are found as 21.8 and 17.8 (MeV).
LORENTZ-COVARIANT AND GAUGE-INVARIANT INSTANTANEOUS VACUUM FOR EXTERNAL FIELD PROBLEMS
Authors: CAPRI A. Z. , ROY S. M.
Published: November 2004

For a Dirac field coupled to time-dependent external electromagnetic field we define an instantaneous (on a fixed spacelike surface) causal vacuum respecting Lorentz covariance and gauge invariance. The instantaneous particle states on this surface are then defined covariantly and connected to states at another time by a Bogoliubov transformation.
RENORMALIZATION-GROUP STUDY OF THE MASSIVE SINE–GORDON THEORY AND PHASE STRUCTURE OF THE ABELIAN HIGGS MODEL
Authors: ICHINOSE IKUO , MUKAIDA HISAMITSU
Published: November 2004

Mapping the Abelian Higgs model to the massive sine–Gordon theory, the phase structure of the Abelian Higgs model is studied. The effect of interaction between instantons in the Abelian Higgs model is treated through the renormalization-group study of the massive sine–Gordon model. In the small dynamical-mass region the interaction between instantons is not negligible, and the effective density of instantons becomes very low at long distance (over the crossover distance) by the pairing mechanism. Therefore, the Abelian Higgs model reduces to a massive scalar theory interacting with very dilute instantons. In the large dynamical-mass region, the pairing mechanism of instanton and anti-instanton does not occur. This crossover phenomenon can be observed by the Wilson loop of a fractional charge. The relationship with the massive Schwinger–Thirring model is also discussed. It is also shown that the recently studied topological-field region is an ultraviolet fixed point of the renormalization-group flow.
THERMO FIELD DYNAMICS IN TIME REPRESENTATION
Authors: YAMANAKA Y. , UMEZAWA H. , NAKAMURA K. , ARIMITSU T.
Published: November 2004

Making use of the thermo field dynamics (TFD) we formulate a calculable method for time-dependent nonequilibrium systems in a time representation (t-representation) rather than in the k0-Fourier representation. The corrected one-body propagator in the t-representation has the form of B−1 (diagonal matrix) B (B being a thermal Bogoliubov matrix). The number parameter in B here is the observed number (the Heisenberg number) with a fluctuation. With the usual definition of the on-shell self-energy a self-consistent renormalization condition leads to a kinetic equation for the number parameter. This equation turns out to be the Boltzmann equation, from which the entropy law follows.
STRUCTURE OF TOPOLOGICAL LATTICE FIELD THEORIES IN THREE DIMENSIONS
Authors: CHUNG STEPHEN-WEI , FUKUMA MASAFUMI , SHAPERE ALFRED
Published: November 2004

We construct and classify topological lattice field theories in three dimensions. After defining a general class of local lattice field theories, we impose invariance under arbitrary topology-preserving deformations of the underlying lattice, which are generated by two new local lattice moves. Invariant solutions are in one-to-one correspondence with Hopf algebras satisfying a certain constraint. As an example, we study in detail the topological lattice field theory corresponding to the Hopf algebra based on the group ring C[G], and show that it is equivalent to lattice gauge theory at zero coupling, and to the Ponzano-Regge theory for G = SU (2).
MAGNETIC MOMENT OF ELECTRONS NEAR COSMIC STRINGS
Authors: MAKI TAKUYA , SHIRAISHI KIYOSHI
Published: November 2004

We study the effect of background geometry generated by a thin cosmic string on the anomalous magnetic moment of the electron. We find that the magnitude of the quantum correction to the magnetic moment depends on the distance from the cosmic string as well as on the deficit angle.
TOPOLOGICAL DEFECTS AND STRUCTURE FORMATION
Authors: BRANDENBERGER ROBERT H.
Published: November 2004

Topological defects are produced during phase transitions in the very early Universe. They arise in most unified theories of strong, weak and electromagnetic interactions. This article focuses on the role of topological defects in cosmology, with particular emphasis on the models of structure formation based on defects. The role of topological defects in baryogenesis is also reviewed.
ON THE MOTION OF HEAVY QUARKS INSIDE HADRONS: UNIVERSAL DISTRIBUTIONS AND INCLUSIVE DECAYS
Authors: BIGI I.I. , SHIFMAN M.A. , URALTSEV N.G. , VAINSHTEIN A.L.
Published: November 2004

In previous papers we have pointed out that there exists a QCD analog of the phenomenological concept of the so-called Fermi motion for the heavy quark inside a hadron. Here we show in a more detailed way how this comes about and we analyze the limitations of this concept. Nonperturbative as well as perturbative aspects are included. We emphasize both similarities and differences to the well-known treatment of deep inelastic lepton-nucleon scattering. We derive a model-independent lower bound on the kinetic energy of the heavy quark inside the hadron.
ASYMPTOTIC ANALYSIS AND SPECTRUM OF THREE ANYONS
Authors: DATE G. , KRISHNA M. , MURTHY M.V.N.
Published: November 2004

The spectrum of anyons confined in a harmonic oscillator potential shows both linear and nonlinear dependence on the statistical parameter. While the existence of exact linear solutions has been shown analytically, the nonlinear dependence has been arrived at by numerical and/or perturbative methods. We develop a method which shows the possibility of a nonlinearly interpolating spectrum. To be specific we analyze the eigenvalue equation in various asymptotic regions for the three-anyon problem.
“ENVIRONMENTALLY FRIENDLY” RENORMALIZATION
Authors: O’CONNOR DENJOE , STEPHENS C.R.
Published: November 2004

We analyze the renormalization of systems whose effective degrees of freedom are described in terms of fluctuations which are “environment”-dependent. Relevant environmental parameters considered are: temperature, system size, boundary conditions and external fields. The points in the space of “coupling constants” at which such systems exhibit scale invariance coincide only with the fixed points of a global renormalization group which is necessarily environment-dependent. Using such a renormalization group we give formal expressions to two loops for effective critical exponents for a generic crossover induced by a relevant mass scale g. These effective exponents are seen to obey scaling laws across the entire crossover, including hyperscaling, but in terms of an effective dimensionality, deff=4−γλ, which represents the effects of the leading irrelevant operator. We analyze the crossover of an O(N) model on a d-dimensional layered geometry with periodic, antiperiodic and Dirichlet boundary conditions. Explicit results to two loops for effective exponents are obtained using a [2/1] Padé-resummed coupling, for: the “Gaussian model” (N=−2), spherical model (N=∞), Ising model (N=1), polymers (N=0), XY model (N=2) and Heisenberg (N=3) models in four dimensions. We also give two-loop Padé resummed results for a three-dimensional Ising ferromagnet in a transverse magnetic field and corresponding one-loop results for the two-dimensional model. One-loop results are also presented for a three-dimensional layered Ising model with periodic, Dirichlet and antiperiodic boundary conditions. Asymptotically the effective exponents are in excellent agreement with known results.
NONINTEGRABLE PHASE DYNAMICS IN TWO-DIMENSIONAL GAUGE MODELS
Authors: SARADZHEV FUAD M.
Published: November 2004

In two-dimensional gauge models the nonintegrable phases of the line Wilson integrals are the only physical gauge field degrees of freedom, providing the gauge field diminishes rather rapidly at spatial infinities. We construct a “physical” quantum Hamiltonian in terms of the physical degrees of freedom for the Schwinger model and the chiral Schwinger model. We show that in the latter case the physical quantum picture can be formulated in two equivalent ways: either in terms of the fermionic matter degrees of freedom moving in a linearly rising background electric field, or in terms of matter fields with exotic statistics.
SPACE-TIME VARIABLE SUPERSTRING VACUA (CALABI-YAU COSMIC YARN)
Authors: GREEN PAUL S. , HÜBSCH TRISTAN
Published: November 2004

In a general superstring vacuum configuration, the “internal” space (sector) varies in space-time. When this variation is nontrivial only in two spacelike dimensions, the vacuum contains static cosmic strings with finite energy per unit length and which is, up to interactions with matter, an easily computed topological invariant. The total space-time is smooth although the “internal” space is singular at the center of each cosmic string. In a similar analysis of the Wick-rotated Euclidean model, these cosmic strings acquire expected self-interactions. Also, a possibility emerges to define a global time in order to rotate back to the Lorentzian case.
RINGS AND BALLS
Authors: BREKKE LEE , IMBO TOM D. , HUGHES SHANE J.
Published: November 2004

We examine the various linkings in space-time of “ball-like” and “ring-like” topological solitons in certain nonlinear sigma models in 2+1 and 3+1 dimensions. By going to theories where soliton overlaps are forbidden, these linkings become homotopically nontrivial and can be studied by investigating the topology of the corresponding configuration spaces. Our analysis reveals the existence of topological terms which give the linking number of the world tubes of distinct species of ball solitons in 2+1 dimensions, or which in 3+1 dimensions count the number of times a ball or ring soliton threads through the center of a ring of a different species. We explicitly construct these terms for our models, and generalize them to cases where soliton overlaps are no longer strictly forbidden so the terms are no longer purely topological. One of the (3+1)-dimensional theories we consider also has topological solitons which consist of two rings (of distinct species) linked in space.
EXTRACTION OF INFRARED DIVERGENCES IN THE DIMENSIONAL REGULARIZED TWO-LOOP LADDER GRAPH
Authors: RAKOWSKI M. , SAVATIER F.
Published: November 2004

We consider the evaluation of the fundamental scalar integral in the on-shell two-loop ladder graph with different external masses and arbitrary transfer momentum. A method for cleanly extracting the infrared divergences in the Feynman parameter integrals using dimensional regularization is presented, and we analyze one of the finite part contributions to this integral.
STRONG–WEAK COUPLING DUALITY IN FOUR-DIMENSIONAL STRING THEORY
Authors: SEN ASHOKE
Published: November 2004

We present several pieces of evidence for strong–weak coupling duality symmetry in the heterotic string theory, compactified on a six-dimensional torus. They include symmetry of the (1) low energy effective action, (2) allowed spectrum of electric and magnetic charges in the theory, (3) allowed mass spectrum of particles saturating the Bogomol'nyi bound, and (4) Yukawa couplings between massless neutral particles and massive charged particles saturating the Bogomol'nyi bound.

This duality transformation exchanges the electrically charged elementary string excitations with the magnetically charged soliton states in the theory. It is shown that the existence of a strong–weak coupling duality symmetry in four-dimensional string theory makes definite predictions about the existence of new stable monopole and dyon states in the theory with specific degeneracies, including certain supersymmetric bound states of monopoles and dyons. The relationship between strong–weak coupling duality transformation in string theory and target space duality transformation in the five-brane theory is also discussed.
A NEW THEORY OF GRAVITATION WITH PARITY-VIOLATING PROPAGATING TORSION
Authors: JHA RAMANAND
Published: November 2004

A new theory of gravitation has been proposed in a more general space–time than Riemannian. It is a generalization of the ECSK and Brans–Dicke (BD) theory of gravitation. It is found that, in contrast to the standard the ECSK theory, a parity-violating propagating torsion is generated by the BD scalar field. The interesting consequence of the theory is that it can successfully predict solar system experimental results to desired accuracy.
THE VANISHING OF A THERMAL EXPECTATION VALUE  IN HOT QCD
Authors: SAWAYANAGI HIROHUMI
Published: November 2004

In QCD at high temperature, a naive perturbative calculation produces infrared divergences. We construct the leading term of an effective potential by summing up diagrams with leading infrared divergences. Based on this potential, we show that the temporal component of gauge field A4 cannot develop a thermal expectation value ≪O(T) at high temperature. We explain why the usual perturbative calculation which was used in previous literature may lead to a wrong result.
FUSION IN CONFORMAL FIELD THEORY AS THE TENSOR PRODUCT OF THE SYMMETRY ALGEBRA
Authors: GABERDIEL MATTHIAS
Published: November 2004

Following a recent proposal of Richard Borcherds to regard fusion as the ringlike tensor product of modules of a quantum ring, a generalization of rings and vertex algebras, we define fusion as a certain quotient of the (vector space) tensor product of representations of the symmetry algebra [Formula: see text]. We prove that this tensor product is associative and symmetric up to equivalence. We also determine explicitly the action of [Formula: see text] on it, under which the central extension is preserved.

Having defined fusion in this way, determining the fusion rules is then the algebraic problem of decomposing the tensor product into irreducible representations. We demonstrate how to solve this for the case of the WZW and the minimal models and recover thereby the well-known fusion rules.

The action of the symmetry algebra on the tensor product is given in terms of a comultiplication. We calculate the R matrix of this comultiplication and find that it is triangular. This seems to shed some new light on the possible rôle of the quantum group in conformal field theory.
KASHIWARA-MIWA MODEL AND OPERATORS ACTING ON SPIN CHAINS
Authors: HU ZHAN-NING
Published: November 2004

In this paper, the Kashiwara-Miwa broken ZN model is discussed and a proof of the Yang-Baxter equation (YBE) is given, which shows that the YBE obtained by Hasegawa and Yamada is a special case. The Q operators acting on spin chains have a structure which is similar to that of the ordinary Hopf algebra, and the quantum algebra sl q(2) with qN=1 can be obtained from these operators as a limit of the elliptic case.
ON THE LANDAU-GINZBURG DESCRIPTION OF N=2 MINIMAL MODELS
Authors: WITTEN EDWARD
Published: November 2004

The conjecture that N=2 minimal models in two dimensions are critical points of a superrenormalizable Landau-Ginzburg model can be tested by computing the path integral of the Landau-Ginzburg model with certain twisted boundary conditions. This leads to simple expressions for certain characters of the N=2 models which can be verified at least at low levels. An N=2 superconformal algebra can in fact be found directly in the noncritical Landau-Ginzburg system, giving further support for the conjecture.
BOUND STATE BOUNDARY S MATRIX OF THE SINE-GORDON MODEL
Authors: GHOSHAL SUBIR
Published: November 2004

We study the boundary S matrix for the reflection of bound states of the two-dimensional sine-Gordon integrable field theory in the presence of a boundary.
WEYL INVARIANCE AND SPURIOUS BLACK HOLES IN TWO-DIMENSIONAL DILATON GRAVITY
Authors: FUJIWARA TAKANORI , IGARASHI YUJI , KUBO JISUKE
Published: November 2004

In two-dimensional dilaton gravity theories, there may exist a global Weyl invariance which makes the black hole spurious. If the global invariance and the local Weyl invariance of the matter coupling are intact at the quantum level, there is no Hawking radiation. We explicitly verify the absence of anomalies in these symmetries for the model proposed by Callan, Giddings, Harvey and Strominger. The crucial observation is that the conformal anomaly can be cohomologically trivial and so not truly anomalous in such dilaton gravity models.
EXTRA SYMMETRIES IN THE EFFECTIVE THEORY OF HEAVY QUARKS
Authors: SOTO JOAN , TZANI RODANTHY
Published: November 2004

Extra symmetries are shown to exist in the effective theory of heavy quarks when both quarks and antiquarks with the same velocity are included. These symmetries mix the quark with the antiquark sector and they resemble the axial type of symmetries. Together with the known flavor and spin symmetries they form a u(4) algebra when a single flavor is considered. It is shown that the full U(4) set of symmetries breaks spontaneously down to U(2)⊗U(2). The Goldstone modes corresponding to the spontaneously broken currents are identified and their relation to physical particles is discussed. Finally, the precise connection of this theory with the fundamental QCD is derived and it is investigated under some approximations. Some physical processes where these extra symmetries may be relevant are pointed out.
N=2 SUPER-W-ALGEBRA IN THE HALF-TWISTED LANDAU-GINZBURG MODEL
Authors: MOHRI KENJI
Published: November 2004

We investigate N=2 extended superconformal symmetry, using the half-twisted Landau-Ginzburg models. The first example is the D2n+2 type minimal model. It has been conjectured that this model has a spin n super-W-current. We check this by direct computations of the BRST cohomology class up to n=4. We observe that for n≤3 the super-W-currents generate the ring isomorphic to the chiral ring of the model with respect to the classical product. We thus conjecture that this isomorphism holds for any n. The next example is the CPn coset model. In this case we find a sort of Miura transformation which gives a simple formula for the super-W-currents of spin {1, 2, …, n} in terms of the chiral superfields. Explicit forms of the super-W-currents and their Poisson brackets are obtained for the CP2 and CP3 cases. We also conjecture that as far as the classical product is concerned, these super-W-currents generate the ring isomorphic to the chiral ring of the model, and this is checked for CP2 coset model.
FUNCTIONAL RELATIONS IN SOLVABLE LATTICE MODELS I: FUNCTIONAL RELATIONS AND REPRESENTATION THEORY
Authors: KUNIBA ATSUO , NAKANISHI TOMOKI , SUZUKI JUNJI
Published: November 2004

We study a system of functional relations among a commuting family of row-to-row transfer matrices in solvable lattice models. The role of exact sequences of the finite-dimensional quantum group modules is clarified. We find a curious phenomenon where the solutions of those functional relations also solve the so-called thermodynamic Bethe ansatz equations in the high temperature limit for sl(r+1) models. Based on this observation, we propose possible functional relations for models associated with all the simple Lie algebras. We show that these functional relations certainly fulfill strong constraints coming from the fusion procedure analysis. The application to the calculations of physical quantities will be presented in the subsequent paper.
FREE MOTION ON THE SPHERES (THE 0+1 NONLINEAR SIGMA MODEL)
Authors: BOYA LUIS J.
Published: November 2004

We study the free motion of a particle on a sphere SN −1, at both the classical and the quantum level. Particular attention is paid to such aspects as ground state degeneracy, orbit space, orthogonal symmetry and its quantum implementation, superintegrability, Casimir operators, spectrum-generating groups, as well as supersymmetric solutions and extensions, all with a view to obtaining a better understanding of the field-theoretic sigma models.
INTERMEDIATE AND HIGH ENERGY BEHAVIOR OF THE SU(5)C MODEL
Authors: BANDYOPADHYAY KRISHNANATH , SARKAR SASWATI , RAY ASIM K.
Published: November 2004

We have shown that the SU(5) C model cannot be distinguished from the Standard Model by measuring the spin-averaged cross-section and forward-backward asymmetry parameters in the processes [Formula: see text] near the Z peak and in the nonresonant sector. However, the e+e−→μ+μ− process can distinguish the SU(5) C model from the Standard Model in the nonresonant sector at the level of 2σ effect when MZ is around 100 GeV.
SOME INTEGRAL FORMULAS FOR THE SOLUTIONS OF THE sl2 dKZ EQUATION WITH LEVEL −4
Authors: NAKAYASHIKI ATSUSHI
Published: November 2004

A direct proof is given for the fact that the integral formula for the XXX limit of the trace of the type I q-vertex operators satisfies the deformed Knizhnik-Zamolodchikov (dKZ) equation with level −4. We have also carried out one-time integration by taking the residue at infinity. As a corollary of these we can construct a family of the integral formulas for solutions to the dKZ equation. Another corollary is the integral formula for the correlation function of the inhomogeneous XXX model, whose number of integrals is less than that of the previously obtained correlator for the XXZ model.
MASSIVE-CONFORMAL DICTIONARY
Authors: MELZER EZER
Published: November 2004

The finite-volume spectrum of an integrable massive perturbation of a rational conformal field theory interpolates between massive multiparticle states in infinite-volume (IR limit) and conformal states, which are approached at zero volume (UV limit). Each state is labeled in the IR by a set of “Bethe-ansatz quantum numbers,” while in the UV limit it is characterized primarily by the conformal dimensions of the conformal field creating it. We present explicit conjectures for the UV conformal dimensions corresponding to any IR state in the ϕ1, 3-perturbed minimal models ℳ(2, 5) and ℳ(3, 5). The conjectures, which are based on a combinatorial interpretation of the Rogers-Ramanujan-Schur identities, are consistent with numerical results obtained previously for low-lying energy levels.
FRACTIONAL QUANTUM HALL EFFECT: CONSTRUCTION OF THE HARTREE–FOCK STATE BY USING TRANSLATIONAL COVARIANCE
Authors: FERRARI R.
Published: November 2004

The formalism introduced in a previous paper is used for discussing the Coulomb interaction of many electrons moving in two space-dimensions in the presence of a strong magnetic field. The matrix element of the Coulomb interaction is evaluated in the new basis, whose states are invariant under discrete translations (up to a gauge transformation). This paper is devoted to the case of low filling factor, thus we limit ourselves to the lowest Landau level and to spins all oriented along the magnetic field. For the case of filling factor νf = 1/u we give an Ansatz on the state of many electrons which provides a good approximated solution of the Hartree–Fock equation. For general filling factor νf = u′/u a trial state is given which converges very rapidly to a solution of the self-consistent equation. We generalize the Hartree–Fock equation by considering some correlation: all quantum states are allowed for the u′ electrons with the same translation quantum numbers. Numerical results are given for the mean energy and the energy bands, for some values of the filling factor (νf = 1/2, 1/3, 2/3, 1/4, 3/4, 1/5, 2/5, 3/5, 4/5). Our results agree numerically with the Charge Density Wave approach. The boundary conditions are shown to be very important: only large systems (degeneracy of Landau level over 200) are not affected by the boundaries. Therefore results obtained on small scale systems are somewhat unreliable. The relevance of the results for the Fractional Quantum Hall Effect is briefly discussed.
MODIFICATION OF NORMAL-STATE AND SUPERCONDUCTING PROPERTIES OF HIGH-Tc OXIDES VIA TREATMENT BY METAL-PHTHALOCYANINES
Authors: GRIGORYAN LEONID , YAKUSHI KYUYA , NARLIKAR A. V. , DUTTA P. K. , SAMANTHA S. B.
Published: November 2004

Exposure of Bi- or Tl-based high-T c oxide powders to vapors of metal-phthalocyanines MPc (M is Zn or Ni) resulted in the formation of a family of new compounds with modified crystal lattice parameters, electronic structure, phonon spectrum and magnetic properties as compared to the starting materials. Based on the combined X ray diffraction, scanning tunneling microscopy, optical, FT–IR and microwave absorption data, a model of crystal structure is proposed where the key feature is intercalation of MPc molecules between the Bi-O (Tl-O) bilayers. Values of dc magnetization at 300 K varied over two orders of magnitude as a function of chemical composition and nature of the central metal ion in MPc. Measurements of temperature dependence of magnetization of the intercalated samples revealed a divergence at low temperatures between the zero-field and the field-cooled cycles, though of lower magnitude as compared to the starting high-T c oxides. The results of this study suggest that treatment by MPc offers a possibility of controllable variation of key properties of high-T c oxides.
ANALYSIS OF GIANT RESONANT PHOTOEMISSION, MAGNETIC X RAY DICHROISM, AND CIRCULAR DICHROISM IN SPIN POLARIZED PHOTOEMISSION FROM CORE STATES OF FERROMAGNETIC NICKEL
Authors: VAN DER LAAN G.
Published: November 2004

The strong variations observed in the satellite and multiplet structure of photoemission at resonance with a deep core level and in the circular dichroism and spin resolved photoemission provide an interesting method to determine the electronic structure of correlated materials as well as the possibility to assign the peak structures. Analysis of these effects in the x ray absorption and photoemission of ferromagnetic nickel using an Anderson impurity model suggest that nickel has a ground state with d weights of around 15% d8, 50% d9 and 35% d10, and that its bulk orbital magnetic moment of 0.053 μ B is strongly enhanced at the surface.
PERTURBED WAVEFUNCTIONS OF THE EXCITED STATES OF HYDROGEN ATOM IN STARK EFFECT
Authors: SAPRA G. K. , BHASIN V. S. , KOTHARI L. S.
Published: November 2004

We extend the procedure originally suggested by Dalgarno and Lewis in studying the second-order Stark effect for the ground-state hydrogen atom to the excited states. We solve the perturbation equations for the excited states of hydrogen atom placed in an external electric field to obtain expressions for the perturbed wavefunctions. Here the emphasis is on studying in detail the nature of the perturbed wavefunction rather than energy shifts as investigated in most of the attempts made so far. The effect of the electric field on these wavefunctions is analysed and the values of the electric polarizability of the hydrogen atom in the excited states obtained in this way are compared with the earlier work.