bluuebunny/crossref_metadata_2025 huggingface dataset:
FEYNMAN PATH-INTEGRAL FOR THE SUM OF THE GLOBAL AND LOCAL KAC-MOODY CHARACTERS
Authors: BAAQUIE BELAL E.
Published: November 2004

Global Kac-Moody characters are defined for arbitrary maps from S1 to G. A pathintegral expression is obtained for the sum over the unitary representations of the global and local Kac-Moody characters for an arbitrary compact group using a functional differential realization of the Kac-Moody generators. The U(1) case is then solved exactly, and the global characters for a given representation are obtained.
TOP QUARK MASS IN THE CONDENSATE MODEL AND THE POSSIBILITY OF COLORED BOSONS
Authors: KUNDU ANIRBAN , DE TRIPTESH , DUTTA-ROY BINAYAK
Published: November 2004

The dynamical electroweak symmetry breaking of the Standard Model triggered by a top quark condensate (induced by an effective strong interaction, associated with a highenergy scale, of the form [Formula: see text]) usually requires an embarrassingly large top quark mass. A suggestion that this problem could be avoided through the introduction of an additional interaction [Formula: see text] (where [Formula: see text] are SU(3)c generators á la Okubo) is analyzed using the renormalization group approach. The mass of the top quark and the concomitant emergence of colored composite bosons is discussed.
REDUCTION OF THE TWO-BODY PROBLEM WITH SPIN IN (2+1)-DIMENSIONAL GRAVITY
Authors: MANSOURI F. , FALBO-KENKEL M.K.
Published: November 2004

The two-body problem with spin in (2+1)-dimensional gravity is analyzed nonperturbatively. Utilizing topological methods similar to those used in the reduction of the spinless case, we show that the general two-body problem with spin can again be reduced to an equivalent one-body formalism. We give exact expressions for the mass and spin of the reduced problem.
ON THE FADDEEV-JACKIW QUANTIZATION OF THE LINEAR CONSTRAINT CHIRAL BOSON
Authors: WOTZASEK CLOVIS
Published: November 2004

The symplectic quantization method of Faddeev and Jackiw with true constraints is employed to study two-dimensional self-dual scalar fields with linear chiral constraints. A gauge invariant embedding of the previous model is explicitly obtained and investigated under Faddeev-Jackiw point of view.
DO PRESENT LEP DATA PROVIDE EVIDENCE FOR ELECTROWEAK CORRECTIONS?
Authors: NOVIKOV V.A. , OKUN L.B. , VYSOTSKY M.I.
Published: November 2004

The Born approximation, based on [Formula: see text] instead of α, reproduces all electroweak precision measurements within their (1σ) accuracy. The low upper limits for the genuinely electroweak corrections constitute one of the major achievements of LEP. The astonishing smallness of these corrections results from the cancellation of a large positive contribution from the heavy top quark and large negative contributions from all other virtual particles. It is precisely the non-observation of electroweak radiative corrections that places stringent upper and lower limits on the top mass.
SUBTHRESHOLD ANTIPROTON PRODUCTION IN HEAVY-ION COLLISIONS
Authors: SPIELES C. , JAHNS A. , SORGE H. , STÖCKER H. , GREINER W.
Published: November 2004

We present a RQMD calculation of antiproton yields and their momentum distribution in Ne+NaF collisions at 2 GeV /u. The antiprotons can be produced below threshold due to multi-step excitations for which meson-baryon interactions play a considerable role. In this system the annihilation probability for an initially produced antiproton is predicted to be about 65%.
q-DEFORMED BAKER-CAMPBELL-HAUSDORFF FORMULA
Authors: CHUNG WON-SANG
Published: November 2004

In this paper we obtain and prove the q-deformed Baker-Campbell-Hausdorff formula.
HOPF TERM, LOOP ALGEBRAS AND THREE-DIMENSIONAL NAVIER-STOKES EQUATION
Authors: MATSUO YUTAKA
Published: November 2004

The dynamics of the three-dimensional perfect fluid is equivalent to the motion of vortex filaments or "strings." We study the action principle and find that it is described by the Hopf term of the nonlinear sigma model. The Poisson bracket structure is described by the loop algebra, for example, the Virasoro algebra or the analog of O(3) current algebra. As a string theory, it is quite different from the standard Nambu-Goto string in its coupling to the extrinsic geometry. We also analyze briefly the two-dimensional case and give some emphasis on the w1+∞ structure.
KINK FINDING IN THE ALEPH TPC USING NEURAL NETWORKS
Authors: STIMPFL-ABELE GEORG
Published: November 2004

The task of finding the decays of charged tracks inside a tracking device is divided into two parts. First a neural net is used to recognize kinks in well-reconstructed tracks. If a kink has been found, a second net determines the radial position of the decay vertex. Both algorithms use feed-forward nets with error back-propagation. Very good performance is obtained in comparison with conventional methods using simulated data from the ALEPH TPC.

The behavior of the nets is analyzed by studying the correlations between the inputs and the output.
NEW TENSOR PARTICLES FROM $\pi^- \to e^- \tilde \nu\gamma$ AND K+ → πoe+ν DECAYS
Authors: CHIZHOV M. V.
Published: November 2004

The inserting of antisymmetric tensor fields into the standard electroweak theory may explain the recent experiments on [Formula: see text] and K+ → πoe+ν decays. New intermediate particles can induce the destructive interference in the pion decay and the nonzero tensor and scalar form factors in the kaon decay.
TOP-LOOP CORRECTION TO NEUTRAL PSEUDO-GOLDSTONE BOSON DECAYS
Authors: YUE CHONG XING , LU GONG RU , YANG JIN MIN
Published: November 2004

We develop the total effective Lagrangian of the two-photon couplings to the color-singlet neutral pseudo-Goldstone boson P0, as predicted in technicolor models. We calculate the effect of t-quark loop on the coupling. Such effect significantly changes the coupling strength which ordinarily arise from the Wess-Zumino term.
LEPTONIC DECAY WIDTH OF VECTOR MESONS IN A FIELD-THEORETIC QUARK MODEL
Authors: PANDA A. R. , ROY K. C.
Published: November 2004

We consider here the leptonic decay of vector mesons ρ, ω, ϕ, ψ and ϒ through one photon mechanism in the lowest order, and calculate their decay widths as well as the decay constants based on a field-theoretic quark model where the constituent quark field operators are described with an ansatz to satisfy equal time algebra and the translationally invariant hadron states are described with harmonic oscillator wave functions. With the harmonic oscillator radii for vector mesons and the constituent quark masses as used earlier in other investigations, the present calculations show a reasonable agreement with the experimental data in light as well as heavy flavor sectors, where available.
RENORMALIZING THE GAUGED NAMBU-JONA-LASINIO MODEL
Authors: KONDO KEI-ICHI , TANABASHI MASAHARU , YAMAWAKI KOICHI
Published: November 2004

Non-perturbative renormalization is given for both symmetric and spontaneously broken phases of the chiral symmetry in the gauged Nambu-Jona-Lasinio model. We explicitly obtain β-function having non-trivial uv fixed line for the renormalized coupling as well as the bare one. In both phases the anomalous dimension is very large (> 1) near the fixed line without discontinuity.
FROM ONE-MATRIX MODEL TO KONTSEVICH MODEL
Authors: AMBJØRN J. , KRISTJANSEN C. F.
Published: November 2004

Loop equations of matrix models express the invariance of the models under field redefinitions. We use loop equations to prove that it is possible to define continuum times for the generic Hermitian one-matrix model such that all correlation functions in the double scaling limit agree with the corresponding correlation functions of the Kontsevich model expressed in terms of KdV times. In addition the double scaling limit of the partition function of the Hermitian matrix model agrees with the τ-function of the KdV hierarchy corresponding to the Kontsevich model (and not the square of the τ-function) except for some complications at genus zero.
q-HYPERGEOMETRIC FUNCTIONS IN THE FORMALISM OF FREE FIELDS
Authors: MOROZOV ALEXEI , VINET LUC
Published: November 2004

We describe a representation of the q-hypergeometric functions of one variable in terms of correlators of vertex operators made out of free scalar fields on the Riemann sphere.
HAMILTONIAN FORMULATION OF SL(3) Ur-KdV EQUATION
Authors: CHUNG B. K. , JOO K. G. , NAM SOONKEON
Published: November 2004

We give a unified view of the relation between the SL(2) KdV, the mKdV, and the Ur-KdV equations through the Fréchet derivatives and their inverses. For this we introduce a new procedure of obtaining the Ur-KdV equation, where we require that it has no nonlocal operators. We extend this method to the SL(3) KdV equation, i.e. Boussinesq (Bsq) equation and obtain the Hamiltonian structure of Ur-Bsq .equation in a simple form. In particular, we explicitly construct the Hamiltonian operator of the Ur-Bsq system which defines the Poisson structure of the system, through the Fréchet derivative and its inverse.
2D SUPERGRAVITY WITH APPLICATIONS TO INTEGRABLE MODELS
Authors: ARNAUDOV L. N. , PRODANOV E. M. , CH. RASHKOV R.
Published: November 2004

In recent work two different approaches for obtaining the covariant action of 2D quantum supergravity are developed. The first one is based on Hamiltonian reduction of flat OSP (2|1) connection in holomorphic polarization. Adding extra degrees of freedom with the help of gauging procedure, the action and the superconformal Ward identity are obtained. It is shown that super-Virasoro transformations preserve the form of the Lax connection and therefore are symmetries of the sKdV equations. In the second approach starting with Chern-Simons theory and using non-canonical polarization the zero-curvature condition entails the same results.
GONIHEDRIC STRING AND ASYMPTOTIC FREEDOM
Authors: SAVVIDY G. K. , SAVVIDY K. G.
Published: November 2004

Very few natural basic principles allow to extend Feynman integral over the paths to an integral over the surfaces so that they coincide at long time scale, that is when the surface degenerates into a single particle world line. In the classical approximation the loop Green functions have perimeter behavior. That corresponds to the free quarks. Quantum fluctuations of the surface generate nonzero string tension, that is the area law and we have quark confinement. In this string theory confinement and asymptotic freedom can coexist.
ON A FERMIONIC REALIZATIONS OF W-TYPE SYMMETRIES
Authors: KAVALOV AN. R. , MKRTCHYAN R.L.
Published: November 2004

The simplest W-type algebra is considered, which includes spin-3/2 and 1 currents, with the aim of finding all its realizations in the free fermion theory through the currents of the type γi1…i2sψi1 … ψi2s. The solution of this problem appears to be related to some problem in the theory of Lie algebras, and we give a classification of the solutions for γ tensors, which turn out to be connected with structure constants of Lie algebras. This is in parallel with previously known similar bosonic construction, connected with symmetric counterpart of the Lie algebras — the Jordan algebras.
DIFFERENTIAL CALCULI ON h-DEFORMED BOSONIC AND FERMIONIC QUANTUM PLANES
Authors: KOBAYASHI TATSUO
Published: November 2004

We study differential calculus on h-deformed bosonic and fermionic quantum space. It is shown that the fermionic quantum space involves a parafermionic variable as well as a classical fermionic one. Further we construct the classical su(2) algebra on the fermionic quantum space and discuss a mapping between the classical su(2) and the h-deformed su(2) algebras.
SPACE-TIME TORSION, BROKEN LORENTZ SYMMETRY AND INFLATION IN THE EARLY UNIVERSE
Authors: CHATTERJEE P. , BHATTACHARYA B.
Published: November 2004

We have shown here, a possible scheme of inflationary scenario at an early stage of the universe during the radiation dominated era by introducing a local Lorentz symmetry violating term in the space-time torsion of Einstein-Cartan action in E(4,1) space. This 'additional' mechanism for producing inflation may also suggest the answer to the question of the local relative abundance of particles over antiparticles in the observed universe.
COMMENTS ON WITTEN INVARIANTS OF THREE-MANIFOLDS FOR SU(2) AND Zm
Authors: RAMA S. KALYANA , SEN SIDDIHARTHA
Published: November 2004

The values of the Witten invariants, IW, of the lens space L(p,1) for SU (2) at level k are obtained for arbitrary p. A duality relation for IW when p and k are interchanged, valid for asymptotic k, is observed. A method for calculating IW for any group G is described. It is found that IW for Zm, even for m=2, distinguishes three-manifolds quite effectively.
ON QUANTUM INTEGRABILITY AND THE LEFSCHETZ NUMBER
Authors: NIEMI ANTTI J. , PALO KAUPO
Published: November 2004

Certain phase space path integrals can be evaluated exactly using equivalent cohomology and localization in the canonical loop space. Here we extend this to a general class of models. We consider Hamiltonians which are a priori arbitrary functions of the Cartan subalgebra generators of a Lie group which is defined on the phase space. We evaluate the corresponding path integral and find that it is closely related to the infinitesimal Lefschetz number of a Dirac operator on the phase space. Our results indicate that equivariant characteristic classes could provide a natural geometric framework for understanding quantum integrability.
TOWARDS THE DETERMINATION OF THE π-p → f2(1270)n REACTION CROSS-SECTION
Authors: ACHASOV N. N. , SHESTAKOV G. N.
Published: November 2004

In this letter, the necessity of a more precise estimation of the data on the reaction π-p → f2(1270)n → π0π0n is mentioned. The total cross-section σ(π-p → f2(1270)n) obtained from the data on the reaction π-p → π0π0n is shown to be approximately three times smaller than that following from the π-p → π+π-n data and also four times smaller than the prediction of the one-pion-exchange model. It is very important to resolve this disagreement because the results on the reaction π-p → f2(1270)n → π0π0n are used directly for the normalization of other reaction cross-sections and determination of branching ratios for some resonances.
EVALUATING ONE-LOOP LIGHT-CONE INTEGRALS BY "COVARIANTIZING" THE GAUGE-DEPENDENT POLE
Authors: SUZUKI A. T.
Published: November 2004

Making sure that causality be preserved by means of "covariantizing" the gauge-dependent singularity in the propagator of the vector potential Aμ(x), we show that the evaluation of some basic one-loop light-cone integrals reproduce those results obtained through the Mandelstam-Leibbrandt prescription. Moreover, such a covariantization has the advantage of leading to simpler integrals to be performed in the cone variables (the bonus), although, of course, it introduces an additional α-parameter integral to be performed (the price to pay).
CORRELATORS OF THE KAZAKOV-MIGDAL MODEL
Authors: DOBROLIUBOV M. I. , MAKEENKO YU. , SEMENOFF G. W.
Published: November 2004

We derive loop equations for the one-link correlators of gauge and scalar fields in the Kazakov-Migdal model. These equations determine the solution of the model in the large-N limit and are similar to analogous equations for the Hermitian two-matrix model. We give an explicit solution of the equations for the case of a Gaussian, quadratic potential. We also show how similar calculations in a non-Gaussian case reduce to purely algebraic equations.
RARE FCNC-B DECAYS AT HADRON MACHINES
Authors: CLINE DAVID B.
Published: November 2004

We review the current studies and future prospects for studies of Flavor Changing Neutral Current (FCNC) processes, emphasizing rare B decays. These experiments will be very sensitive to physics beyond the standard model. A key problem in these studies is the method to trigger the detector. We discuss a novel technique that uses an optical-Cherenkov light trigger to select events with significant impact parameters.
qQCD2 AND G/G MODEL
Authors: BOULATOV D. V.
Published: November 2004

The 2D lattice gauge theory with a quantum gauge group SL q(2) is considered. When q=ei2π/(k+2), its weak coupling partition function coincides with the one of the G/G coset model (i.e. equals the Verlinde numbers). However, despite such a remarkable coincidence, these models are not equivalent but, in certain sense, dual to each other.
ON q-COVARIANT WAVE FUNCTIONS
Authors: GILLER S. , GONERA C. , KOSIŃSKI P. , MAJEWSKI M. , MAŚLANKA P. , KUNZ J.
Published: November 2004

The differential realization of the recently proposed deformed Poincaré algebra is considered. The notion of covariant wave functions is introduced and their explicit form in the "minimal" (in Weinberg's sense) case is given. The deformed Dirac equation is constructed.
BEHAVIOR OF CHARGED PARTICLE MOTION IN A MAGNETIC FIELD AND A RETARDING POTENTIAL II – OBSERVATIONS OF THE EXISTENCE OF "FORBIDDEN STATES" AND AHARANOV-BOHM ANALOG IN CLASSICAL MECHANICAL DOMAIN
Authors: VARMA R. K. , PUNITHAVELU A. M.
Published: November 2004

The observations made earlier1 on the existence of discrete 'forbidden' (and allowed) states in a classical mechanical system of charged particle motion in a magnetic field are extended to include the region where the applied retarding potential exceeds the potential equivalent of the electron energy. The electron current flowing to the ground from the anode of the electron gun is found to exhibit strong dips as the potential on the grid of the detector system kept at a distance along the magnetic field, is swept from a large negative value to zero. The observed anode current 'dips' are quite enigmatic since the electrons under the conditions (grid potential far exceeding the cathode potential) are unable to reach the grid, yet they respond to the grid potential changes in quite an unexpected manner. This observation is thus reminiscent of the Aharanov-Bohm effect in quantum mechanics. The dips are moreover found to fit a relation, a modified form of that given in the earlier reported results.
INTERMITTENCY PATTERNS IN PROTON-NUCLEUS INTERACTIONS AT HIGH ENERGY
Authors: MAITY D. K. , BANERJEE P. K. , DAS B. B. , RAVINDRAN D. , BHATTACHARJEE D. K.
Published: November 2004

A study of intermittency in hadron-nucleus and the comparison with nucleus-nucleus interactions is presented. The power law behavior of the factorial moments and the variation of intermittency index with the center-of-mass energy are shown. Results favor the formation of quark-gluon plasma in preference to a cascade mechanism.
CLASSICAL FERMI FLUID AND GEOMETRIC ACTION FOR c=1
Authors: DHAR AVINASH , MANDAL GAUTAM , WADIA SPENTA R.
Published: November 2004

We formulate the c=1 matrix model as a quantum fluid and discuss its classical limit in detail, emphasizing the ħ corrections. We view the fermi fluid profiles as elements of w∞-coadjoint orbit and write down a geometric action for the classical phase space. In the specific representation of fluid profiles as “strings” the action is written in a four-dimensional form in terms of gauge fields built out of the embedding of the “string” in the phase plane. We show that the collective field action can be derived from the above action provided one restricts to quadratic fluid profiles and ignores the dynamics of their “turning points”.
MAXIMAL CP VIOLATION VIA HIGGS-BOSON EXCHANGE
Authors: LAVOURA L.
Published: November 2004

The unitarity of the mixing matrix of the charged Higgs bosons, and the orthogonality of the mixing matrix of the neutral Higgs bosons, are used to derive upper bounds on the values of general CP-violating expressions. The bounds are independent of the total number of Higgs fields in any specific model. They allow us to relax the usual assumption of only one Higgs boson being light. It is natural that the CP violation in the exchange of neutral Higgs bosons between bottom quarks be particularly large.
THE EDGE STATES OF THE BF SYSTEM AND THE LONDON EQUATIONS
Authors: BALACHANDRAN A.P. , TEOTONIO-SOBRINHO P.
Published: November 2004

It is known that the 3D Chern–Simons interaction describes the scaling limit of a quantum Hall system and predicts edge currents in a sample with boundary, the currents generating a chiral U(1) Kac-Moody algebra. It is no doubt also recognized that, in a somewhat similar way, the 4D BF interaction (with B a two-form, dB the dual *j of the electromagnetic current, and F the electromagnetic field form) describes the scaling limit of a superconductor. We show in this paper that there are edge excitations in this model as well for manifolds with boundaries. They are the modes of a scalar field with invariance under the group of diffeomorphisms (diffeos) of the bounding spatial two-manifold. Not all diffeos of this group seem implementable by operators in quantum theory, the implementable group being a subgroup of volume-preserving diffeos. The BF system in this manner can lead to the w1+∞ algebra and its variants. Lagrangians for fields on the bounding manifold which account for the edge observables on quantization are also presented. They are the analogs of the (1+1)-dimensional massless scalar field Lagrangian describing the edge modes of an Abelian Chern-Simons theory with a disk as the spatial manifold. We argue that the addition of “Maxwell” terms constructed from F∧*F and dB∧*dB does not affect the edge states, and that the augmented Lagrangian has an infinite number of conserved charges—the aforementioned scalar field modes—localized at the edges. This Lagrangian is known to describe London equations and a massive vector field. A (3+1)-dimensional generalization of the Hall effect involving vortices coupled to B is also proposed.
STAIRCASE MODELS FROM AFFINE TODA FIELD THEORY
Authors: DOREY PATRICK , RAVANINI FRANCESCO
Published: November 2004

We propose a class of purely elastic scattering theories generalising the staircase model of Al. B. Zamolodchikov, based on the affine Toda field theories for simply-laced Lie algebras g=A, D, E at suitable complex values of their coupling constants. Considering their Thermodynamic Bethe Ansatz (TBA) equations, we give analytic arguments in support of a conjectured renormalisation group flow visiting the neighbourhood of each Wg minimal model in turn.
PERTURBATION THEORY FOR ANTISYMMETRIC TENSOR FIELDS IN FOUR DIMENSIONS
Authors: MAGGIORE N. , SORELLA S.P.
Published: November 2004

Perturbation theory for a class of topological field theories containing antisymmetric tensor fields is considered. These models are characterized by a supersymmetric structure which allows us to establish their perturbative finiteness.
THE CRITICAL POINT OF UNORIENTED RANDOM SURFACES WITH A NONEVEN POTENTIAL
Authors: MARTÍN-DELGADO M.A.
Published: November 2004

The discrete model of the real symmetric one-matrix ensemble is analyzed with a cubic interaction. The partition function is found to satisfy a recursion relation that solves the model. The double scaling-limit of the recursion relation leads to a Miura transformation relating the contributions to the free energy coming from oriented and unoriented random surfaces. This transformation is the same kind as found with a quartic interaction.
MESONS AND DIQUARKS IN A NJL MODEL AT FINITE TEMPERATURE AND CHEMICAL POTENTIAL
Authors: EBERT D. , KALINOVSKY YU. L. , MÜNCHOW L. , VOLKOV M.K.
Published: November 2004

An extended NJL model with [Formula: see text] and (qq)-interactions is studied at finite temperature and baryon number density. We investigate the chiral symmetry breaking, its restoration and the behavior of meson and diquark masses, decay and coupling constants as functions of T and µ.
PHOTOPRODUCTION OF HEAVY QUARKS AS A TOOL FOR INVESTIGATION OF THE SPIN-DEPENDENT GLUON DISTRIBUTIONS
Authors: ALEKHIN S.I. , BORODULIN V.I. , SULTANOV S.F.
Published: November 2004

The possibility for measuring polarized gluon distributions in the process of heavy quark production in the scattering of real photons off polarized fixed target has been considered. The estimates of γ-beam intensities required to determine the polarization asymmetry have been made.
BOUND STATE ENERGIES IN THE 1/N EXPANSION
Authors: JAROSZEWICZ T. , KURZEPA P.S.
Published: November 2004

We derive and solve — in an arbitrary number of dimensions — Omnès-type equations for bound-state energies in weakly coupled quantum field theories. We show that, for theories defined in the 1/N expansion, these equations are exact to leading order in 1/N. We derive and discuss the weak coupling and nonrelativistic limits of the Omnès equations. We then calculate the binding energies and effective bound-state couplings in (1+1), (1+2) and (1+3)-dimensional O(N)-invariant ϕ4 theory. We consider both the scalar and symmetric tensor bound states.
EUCLIDEAN ASYMPTOTIC EXPANSIONS OF GREEN FUNCTIONS OF QUANTUM FIELDS (I) EXPANSIONS OF PRODUCT OF SINGULAR FUNCTIONS
Authors: TKACHOV F. V.
Published: November 2004

The problem of asymptotic expansion of Green functions in perturbative QFT is studied for the class of Euclidean asymptotic regimes. Phenomenological applications are analyzed to obtain a meaningful mathematical formulation of the problem. It is shown that the problem reduces to studying asymptotic expansion of products of a class of singular functions in the sense of the distribution theory. Existence, uniqueness and explicit expressions for such expansions. (As-operation for products of singular functions) in dimensionally regularized form are obtained using the so-called extention principle.
EUCLIDEAN ASYMPTOTIC EXPANSIONS OF GREEN FUNCTIONS OF QUANTUM FIELDS (II) COMBINATORICS OF THE AS OPERATION
Authors: PIVOVAROV G. B. , TKACHOV F. V.
Published: November 2004

The results of Ref. 1 are used to obtain full asymptotic expansions of Feynman diagrams renormalized within the MS scheme in the regimes when some of the masses and external momenta are large with respect to the others. The large momenta are Euclidean, and the expanded diagrams are regarded as distributions with respect to them. The small masses may be equal to zero. The As operation for integrals is defined and a simple combinatorial technique is developed to study its exponentiation. The As operation is used to obtain the corresponding expansions of arbitrary Green functions. Such expansions generalize and improve upon the well-known short-distance, operator-product expansions, the decoupling theorem etc.: e.g. the low-energy effective Lagrangians are obtained to all orders of the inverse heavy mass. The obtained expansions possess the property of perfect factorization of large and small parameters, which is essential for meaningful applications to phenomenology. As an auxiliary tool, the inversion of the R operation is constructed. The results are valid for arbitrary QFT models.
RELATIVISTIC SPIN 1/2 PARTICLE ON THE TOTAL SPACE OF U(1)-MONOPOLE BUNDLE
Authors: IVANOV O. M. , SAVINKOV A. G.
Published: November 2004

A relativistic spin 1/2 particle quantum dynamics on the total space P of principle bundle, which is commonly attributed to Dirac monopole, is described. This dynamics is completely characterized with the help of additional U (1)-bundle P* which turned out to be connected with scattering problem. We formulate the representation in which the Hamiltonian has the most simple form. Lift of the Lorentz group to the total space is constructed.
NONDISPERSIVE WAVES: ENERGY
Authors: HILLION PIERRE
Published: November 2004

We give the expressions for the energy of the nondispersive scalar and electromagnetic waves and the conditions that energy is finite.
THE RELATIVISTIC THEORY FOR PRINCIPAL TRAJECTORIES AND ELECTROMAGNETIC TRANSITIONS OF LIGHT MESONS PART II
Authors: BERDNIKOV E. B. , NANOBASHVILI G. G. , PRON'KO G. P.
Published: November 2004

On the basis of the results of Ref. 1, the electromagnetic transition operator for the relativistic extended object has been constructed. The noncommutativity of charge coordinates makes this problem nontrivial. The system can be considered as a realistic model of light mesons.
HOW MUCH CAN BE LEARNT ABOUT PION WAVE FUNCTION FROM THE DRELL–YAN PROCESS?
Authors: AGAEV SHAHIN S.
Published: November 2004

Contribution of the high twist Feynman diagrams to the dilepton production cross section in pion–hadron collisions is investigated. In calculations the asymptotic, Chernyak–Zhitnitsky and two other pion model wave functions P2, P3 are used. It is shown that this contribution depends on the choice of wave functions and for large dilepton transverse momentum pT and invariant mass Q in the limit [Formula: see text] exceeds the leading one by an order of magnitude. Perspectives of the Drell–Yan process in the context of the pion wave function investigation are discussed.
THE EFFECTIVE STRING OF 3D Z2 GAUGE THEORY AS A c = 1 COMPACTIFIED CFT
Authors: CASELLE M. , GLIOZZI F. , VINTI S. , FIORE R.
Published: November 2004

We report on a high precision Monte Carlo test of the three-dimensional Ising gauge model at finite temperature. The string tension σ is extracted from the expectation values of correlations of Polyakov lines. Agreement with the string tension extracted from Wilson loops is found only if the quantum fluctuations of the flux tube are properly taken into account. The central charge of the underlying conformal field theory is c = 1.
DIFFERENTIAL RENORMALIZATION OF A YUKAWA MODEL WITH γ5
Authors: MANUEL CRISTINA
Published: November 2004

We present a two-loop computation of the beta functions and the anomalous dimensions of a γ5 Yukawa model using differential renormalization. The calculation is carried out in coordinate space without modifying the space–time dimension and no ad hoc prescription for γ5 is needed. It is shown that this procedure is specially suited for theories involving γ5, and it should be considered in analyzing chiral gauge theories.
SPONTANEOUS CP VIOLATION FROM A QUATERNIONIC KALUZA–KLEIN THEORY
Authors: HANLON B. E. , JOSHI G. C.
Published: November 2004

Motivated by the isomorphism between the universal covering group of the six-dimensional Lorentz group and the special linear group over the quaternions, a locally quaternionic covariant theory is postulated to exist in six space–time dimensions. Compactifying onto the space–time M4 ⊗ S2 a complex theory is retrieved on the four-dimensional Minkowski space with the essential quaternionic nature confined to S2. Quaternionic spinors are introduced and a dimensionally reduced theory recovered which exhibits a CP-violating effect via spontaneous symmetry breaking.
ON THE QUANTIZATION OF THE N = 2 SUPERSYMMETRIC NONLINEAR SIGMA MODEL
Authors: ALDAZABAL G. , MALDACENA J. M.
Published: November 2004

A method for quantizing the bidimensional N = 2 supersymmetric nonlinear sigma model is developed. This method is both covariant under coordinate transformations (concerning the order relevant for calculation) and explicitly N = 2 supersymmetric. The operator product expansion of the supercurrent is computed accordingly, including also the dilaton. By imposing the N = 2 superconformal algebra the equations for the metric and the dilaton are obtained. In particular, they imply that the dilaton is a constant.
FUSION ALGEBRAS INDUCED BY REPRESENTATIONS OF THE MODULAR GROUP
Authors: EHOLZER W.
Published: November 2004

Using the representation theory of the subgroups SL 2(ℤp) of the modular group we investigate the induced fusion algebras in some simple examples. Only some of these representations lead to "good" fusion algebras. Furthermore, the conformal dimensions and the central charge of the corresponding rational conformal field theories are calculated. Two series of representations which can be realized by unitary theories are presented. We show that most of the fusion algebras induced by admissible representations are realized in well-known rational models.
A CLASSICAL N = 4 SUPER W ALGEBRA
Authors: PERRET R. E. C.
Published: November 2004

I construct classical superextensions of the Virasoro algebra by employing the Ward identities of a linearly realized subalgebra. For the N = 4 superconformal algebra, this subalgebra is generated by the N = 2 U (1) supercurrent and a spin 0 N = 2 superfield. I show that this structure can be extended to an N = 4 super W3 algebra, and give the complete form of this algebra.
APPLICATION OF THE WORMHOLE MECHANISM TO THE DECAYING COSMOLOGICAL CONSTANT MODEL
Authors: NISHIOKA TSUYOSHI , WADA SUMIO
Published: November 2004

According to some of the recent analyses, the cosmological constant Λ may be extremely small but finite. The decaying cosmological constant model can naturally explain the smallness of Λ from the oldness of our universe, provided that some of the parameters in the Lagrangian are fine-tuned so that the asymptotic value of Λ is zero. In this report we show that Coleman’s wormhole mechanism can naturally explain why the parameters are fine-tuned in this model.
PHYSICS AT THE PLANCK LENGTH
Authors: WHEELER JOHN ARCHIBALD
Published: November 2004

Results of the conference, “String Quantum Gravity and Physics at the Planck Energy Scale,” organized by Dr. Norma Sanchez, in Erice, Sicily, June 21–28, 1992 will appear in Proceedings of the International Workshop of Theoretical Physics, 6th Session, World Scientific Publishing Co. Pte. Ltd., Singapore, 1993. The conference has given new occasion to ask what linkage, if any, ties together particle physics and the quantum theory of gravitation, where this fantastically short distance first displayed its relevance.
THE COVARIANT SCATTERING AND COHOMOLOGY OF W3 STRINGS
Authors: FREEMAN MICHAEL , WEST PETER
Published: November 2004

A general formalism for covariant W3 string scattering is given. It is found necessary to use screening charges that are constructed from the W3 fields including ghosts. The scattering amplitudes so constructed contain within them Ising model correlation functions and agree with those found previously by the authors. Using the screening charge and a picture-changing operator, an infinite number of states in the cohomology of Q are generated from only three states. We conjecture that, apart from discrete states, these are all the states in the cohomology of Q.
QUANTUM RANDOM WALKS AND TIME REVERSAL
Authors: MAJID S.
Published: November 2004

Classical random walks and Markov processes are easily described by Hopf algebras. It is also known that groups and Hopf algebras (quantum groups) lead to classical and quantum diffusions. We study here the more primitive notion of a quantum random walk associated with a general Hopf algebra and show that it has a simple physical interpretation in quantum mechanics. This is by means of a representation theorem motivated from the theory of Kac algebras: If H is any Hopf algebra, it may be realized in Lin(H) in such a way that Δh=W(h⊗1)W−1 for an operator W. This W is interpreted as the time evolution operator for the system at time t coupled quantum-mechanically to the system at time t+δ. Finally, for every Hopf algebra there is a dual one, leading us to a duality operation for quantum random walks and quantum diffusions and a notion of the coentropy of an observable. The dual system has its time reversed with respect to the original system, leading us to a novel kind of CTP theorem.
NON-ABELIAN FLUX TUBE INSTABILITY
Authors: GUENDELMAN E.I. , OWEN D.A. , LEONIDOV A.
Published: November 2004

We investigate the effect of external field boundary conditions of a background chromomagnetic field on the instability (discovered by Nielsen and Olesen) for the vacuum of a non-Abelian field theory. We find that the vacuum is neither stabilized by a one-dimensional nor a two-dimensional cutoff of this magnetic field. However, the vacuum in the presence of flux tubes whose length is restricted to be under a critical value, L0, is stable. Therefore, there is a tendency for flux tubes of lengths greater than L0 to spontaneously fragment into segments each of which is smaller than L0. This corresponds to a dual picture which allows stable electric flux tubes.
QUANTUM GRAVITY AND BLACK HOLE DYNAMICS IN 1+1 DIMENSIONS
Authors: HAMADA KEN-JI , TSUCHIYA ASATO
Published: November 2004

We study the quantum theory of 1+1 dimensional dilaton gravity, which is an interesting toy model of the black hole dynamics. The functional measures are explicitly evaluated and the physical state conditions corresponding to the Hamiltonian and the momentum constraints are derived. It is pointed out that the constraints form the Virasoro algebra without central charge. In the ADM formalism the measures are very ambiguous, but in our formalism they are explicitly defined. Then the new features which are not seen in the ADM formalism come out. A singularity appears at φ2=κ(>0), where κ=(N–51/2)/12 and N is the number of matter fields. Behind the singularity the quantum mechanical region κ>φ2>0 extends, where the sign of the kinetic term in the Hamiltonian constraint changes. If κ<0, the singularity disappears. We discuss the quantum dynamics of a black hole and then give a suggestion for the resolution of the information loss paradox. We also argue the quantization of the spherically symmetric gravitational system in 3+1 dimensions. In the appendix, the differences between the other quantum dilaton gravities and ours are clarified and our status is stressed.
PARA-GRASSMANN EXTENSIONS OF THE VIRASORO ALGEBRA
Authors: FILIPPOV A.T. , ISAEV A.P. , KURDIKOV A.B.
Published: November 2004

The para-Grassmann differential calculus is briefly reviewed. Algebras of the transformations of the para-superplane preserving the form of the para-superderivative are constructed and their geometric meaning is discussed. A new feature of these algebras is that they contain generators of the automorphisms of the para-Grassmann algebra (in addition to Ramond-Neveu-Schwarz-like conformal generators). As a first step in analyzing these algebras we introduce more tractable multilinear algebras not including the new generators. In these algebras there exists a set of multilinear identities based on the cyclic polycommutators. Different possibilities of the closure are therefore admissible. The central extensions of the algebras are given. Their number varies from 1 to [Formula: see text], depending on the form of the closure chosen. Finally, simple explicit examples of the paraconformal transformations are given.
FUSED POTTS MODELS
Authors: KOO W.M. , SALEUR H.
Published: November 2004

Generalizing the mapping between the Potts model with nearest neighbor interaction and the six-vertex model, we build a family of “fused Potts models” related to the spin k/2 U q su (2) invariant vertex model and quantum spin chain. These Potts models still have variables taking values 1, …,Q[Formula: see text] but they have a set of complicated multispin interactions. The general technique to compute these interactions, the resulting lattice geometry, symmetries, and the detailed examples of k=2, 3 are given.

For Q>4, spontaneous magnetizations are computed on the integrable first order phase transition line, generalizing Baxter’s results for k=1.

For Q≤4, we discuss the full phase diagram of the spin 1 (k=2) anisotropic and U q su (2) invariant quantum spin chain [it reduces in the limit Q=4 (q=1) to the much studied phase diagram of the isotropic spin 1 quantum spin chain], Several critical lines and massless phases are exhibited. The appropriate generalization of the valence bond state method of Affleck et al. is worked out.
SU(2)k×SU(2)l/SU(2)k+l COSET CONFORMAL FIELD THEORY AND TOPOLOGICAL MINIMAL MODEL ON HIGHER GENUS RIEMANN SURFACE
Authors: KONNO HITOSHI
Published: November 2004

We consider the Feigin-Fuchs-Felder formalism of the SU (2)k× SU (2)l/ SU (2)k+l coset minimal conformal field theory and extend it to higher genus. We investigate a double BRST complex with respect to two compatible BRST charges, one associated with the parafermion sector and the other associated with the minimal sector in the theory. The usual screened vertex operator is extended to the BRST-invariant screened three-string vertex. We carry out a sewing operation of these vertices and derive the BRST-invariant screened g-loop operator. The latter operator characterizes the higher genus structure of the theory. An analogous operator formalism for the topological minimal model is obtained as the limit l=0 of the coset theory. We give some calculations of correlation functions on higher genus.
REGULARIZATIONS, ANOMALIES AND FERMION NUMBER NONCONSERVATION IN CHIRAL GAUGE THEORIES
Authors: AOKI SINYA
Published: November 2004

We show that the fermion number has to be carried by the gauge field configurations with nonzero winding number in the fermion-number-preserving regularization scheme of chiral gauge theories and that this fermion number is not conserved in the presence of instantons. Furthermore we show that the operator which corresponds to the fermion number is different if the global symmetries of the regularization are different. We point out the problem of the universalities in the Wilson-Yukawa approach for lattice chiral gauge theories.
HEAVY FERMIONS — THEIR MAGNETISM AND SUPERCONDUCTIVITY
Authors: STEGLICH F. , GEIBEL C. , LOIDL A. , SPARN G. , BREDL C. D. , CASPARY R.
Published: November 2004

Heavy-fermion compounds are ideally suited to study cooperative phenomena in highly correlated electron systems. We discuss local-moment magnetism and heavy-fermion band magnetism in the exemplary systems CeCu 2 Ge 2 and Ni-rich Ce(Cu 1− x Ni x )2 Ge 2, respectively. In addition, the coexistence of long-range antiferromagnetic order and heavy-fermion superconductivity in UM 2 Al 3 (M: Ni, Pd) will be addressed.
THERMAL EXPANSION AND MAGNETOSTRICTION OF THE HEAVY-FERMION COMPOUND UPd2Al3
Authors: MODLER R. , GLOOS K. , GEIBEL C. , KOMATSUBARA T. , SATO N. , SCHANK C. , STEGLICH F.
Published: November 2004

We report on thermal expansion and magnetostriction of the new hexagonal heavy fermion magnetic superconductor UPd 2 Al 3. Measurements were taken on monocrystalline samples between 0.1K and 20K in magnetic fields up to 4T. Both thermal expansion and magnetostriction are strongly anisotropic and are dominated by magnetic effects. In an applied magnetic field, the thermal expansion anomaly observed near T c seems to be of first order.
THERMOPOWER OF URANIUM-BASED HEAVY FERMIONS
Authors: GRAUEL A. , FROMM D. , GEIBEL C. , STEGLICH F. , SATO N. , KOMATSUBARA T.
Published: November 2004

The thermoelectric power S(T) of single crystals of the antiferromagnetically ordered heavy-fermion superconductor UPd 2 Al 3( T N = 14K , T c = 2K ) as well as of polycrystalline UNi 2 Al 3( T N = 4.6K , T c = 1K ), UPd 2 Al 3 and of the ternary heavy-fermion system UCu 4+ x Al 8− x has been measured in the temperature range 2K ≤ T ≤ 350K . A temperature dependence of the thermopower, S(T) = A · T /(1+ T / T ′), was found at sufficiently high temperatures for all of these systems and for the well known heavy-fermion compounds UBe 13 and UPt 3.
ON THE THEORY OF THE HIGH-TcSUPERCONDUCTING MATERIALS
Authors: Fulde Peter
Published: November 2004

Methods are described which can be used for an analytical description of the strong electron correlations in the planes of the Cu–O based high-Tc superconducting materials. One is a projection technique which is applied in order to calculate the photoelectron and inverse photoelectron spectra for the cases of half filling and hole doping of the Cu–O planes. Good agreement with the results of exact diagonalization of (CuO2)4 clusters is obtained, proving the usefulness of the method. Another one is the concept of string states which can be applied to study the t–J model. Also in this case a number of numerical findings can be reproduced and improved by this analytic method.
SINGLE PARTICLE GREEN'S FUNCTION AND QUANTUM MAGNETIC OSCILLATION IN VORTEX STATE OF UNCONVENTIONAL SUPERCONDUCTORS
Authors: MAKI KAZUMI
Published: November 2004

Within weak-coupling model we construct the superconducting order parameter in the vortex states of the axial and hybrid wave function. In terms of these order parameters the quasi-particle Green's function in the vortex state in the vicinity of upper critical field is constructed. In general the most important modification on the quantum oscillation in the vortex state is increase of the damping constant (or the Dingle temperature). However, since this extra term is proportional to the average of | f |2 over the electron orbit at the belly or neck of the Fermi surface, we find that this exrtra term vanishes for the hybrid state for both [Formula: see text] and [Formula: see text], while it vanishes in the axial state only for [Formula: see text]. This should provide a unique probe to the nature of the superconducting wave functions.
PROPERTIES OF SPIN GLASS SUPERCONDUCTORS
Authors: CARBOTTE J. P. , PEREZ-GONZALEZ A. , NICOL E. J.
Published: November 2004

Magnetic impurities at random sites on a lattice and interacting via a long range indirect Rudermann–Kittel–Kasuya–Yosida interaction, can undergo a spin glass transition due to the importance of frustration and competing interactions. Within a simple model of the freezing transition in which the effect of the magnetism on the superconducting electrons reduces to a temperature dependent effective scattering time, we have worked out several superconducting properties and here present results for the upper critical magnetic field. We find that its temperature dependence is profoundly altered over the pure case and strongly reflects the temperature dependence of the magnetic microscopic parameters.
ANISOTROPIC SUPERCONDUCTING PROPERTIES OF YBa2Cu3O7 BASED THIN FILMS AND SUPERLATTICES
Authors: ADRIAN H. , JAKOB G. , TOMÉ-ROSA C. , SCHMITT M. , WAGNER P. , HAHN Th. , KLUGE Th. , SPECKMANN M.
Published: November 2004

Superconductivity in high-Tc oxides originates from the presence of (CuO2)-planes which lead to highly anisotropic normal and superconducting transport properties. The short coherence length ξc ≈ 1 to 3Å causes a spatial variation of the order parameter along the c-direction with dramatic consequences on the vortex dynamics. As model systems to study the influence of structural changes we prepared epitaxial YBa 2( Cu 1−x TM x)3 O 7 films ( TM = Zn and Ni), Bi 2 Sr 2 CaCu 2 O 8 films and coherent YBa 2 Cu 3 O 7/ PrBa 2 Cu 3 O 7 superlattices. Measurements of the critical current density [Formula: see text] clearly reveal the intrinsic pinning mechanism in YBa 2 Cu 3 O 7 for B ⊥ c at low temperatures which disappears approaching Tc. Small transition metal dopings act as pinning centers reducing dissipation due to thermally activated flux movement. The decoupling of the (CuO2)-layers in the superlattices causes a transition from anisotropic 3d to 2d behavior. Therefore the superconducting properties in external magnetic fields, which resemble closely those of Bi 2 Sr 2 CaCu 2 O 8 films, are dominated by the field component parallel to the c-axis. For B ⊥ c the resistive transitions ρ (B, T) and the critical current density jc (B, T) are nearly field independent.
SUCCESSIVE TRANSITIONS IN YBa2Cu4O8 CERAMIC SUPERCONDUCTOR BY DC AND AC MAGNETIC MEASUREMENTS
Authors: KAWACHI M. , HAGIWARA M. , MIYOSHI K. , MATSUURA M. , KOYAMA K.
Published: November 2004

Ordering of a YBa 2 Cu 4 O 8 ceramic superconductor is investigated by DC and AC magnetic measurements. Successive transitions are found at two temperatures T c1 (= 80 K ) and T c2 (= 30 K ) and identified as those from the normal state into a superconductive order inside cach grain with inter-grain disorder and from the intermediate state into the inter-grain(bulk) superconductive state over the whole sample, respectively. Linear and nonlinear responses to AC magnetic excitation at very low frequencies revealed a remarkable anomaly around T c2 and T c1 , reflecting the critical fluctuation at the transitions.