bluuebunny/crossref_metadata_2025 huggingface dataset:
WARD IDENTITIES FOR AFFINE-VIRASORO CORRELATORS
Authors: HALPERN M.B. , OBERS N.A.
Published: November 2004

Generalizing the Knizhnik-Zamolodchikov equations, we derive a hierarchy of nonlinear Ward identities for affine-Virasoro correlators. The hierarchy follows from null states of the Knizhnik-Zamolodchikov type and the assumption of factorization, whose consistency we verify at an abstract level. Solution of the equations requires concrete factorization ansätze, which may vary over affine-Virasoro space. As a first example, we solve the nonlinear equations for the coset constructions, using a matrix factorization. The resulting coset correlators satisfy first-order linear partial differential equations whose solutions are the coset blocks defined by Douglas.
MAGNETIC MOMENTS OF OCTET BARYONS IN A RELATIVISTIC POTENTIAL MODEL WITH PIONIC AND CENTER OF MASS CORRECTIONS
Authors: BARIK N. , JENA S.N. , RATH D.P.
Published: November 2004

The magnetic moments of the octet baryons are calculated in a chiral symmetric inde-pendent quark potential model of the form [Formula: see text] The residual interaction arising from the quark-pion coupling over and above the dominant confining one represented by this phenomenological potential, is treated as a low order perturbation. The correction due to center of mass motion is also taken into account appropriately. The results are in reasonable agreement with the experimental data.
MASSLESS SCALAR FIELDS IN NON-ABELIAN KALUZA-KLEIN THEORY
Authors: ARIK M. , GABAY V.
Published: November 2004

We investigate the presence of massless scalar fields in a Kaluza—Klein theory based on a dimensionally continued Euler-form action. We show that massless scalar fields exist provided that the internal space is a direct product of two irreducible manifolds. The condition of a vanishing effective four-dimensional cosmological constant and the presence of a graviton, gauge fields and massless scalar fields can be satisfied if both irreducible manifolds have odd dimensions and the sum of these dimensions is equal to the dimension of the Euler form.
ON LOCAL QUANTUM DEFORMATIONS OF ANTISYMPLECTIC DIFFERENTIAL
Authors: BATALIN I.A. , TYUTIN I.V.
Published: November 2004

Quantum deformations of the nilpotent operator Δ, a foremost ingredient of the fieldantifield BV-formalism, are studied at the local level. It is found that the nilpotency-preserving local deformations are described by the formula Δ→ exp (−U)Δ exp (U)+δ, δ= const , comprehensively.
COMPUTATION OF β′(gc) AT O(1/N2) IN THE O(N) GROSS-NEVEU MODEL IN ARBITRARY DIMENSIONS
Authors: GRACEY J.A.
Published: November 2004

By using the corrections to the asymptotic scaling forms of the fields of the O(N) Gross-Neveu model to solve the dressed skeleton Schwinger-Dyson equations, we deduce the critical exponent corresponding to the β function of the model at O(1/N2).
WORLD-SHEET INSTANTONS IN THE 2D BLACK HOLE
Authors: YUNG A.V.
Published: November 2004

Nonperturbative effects in the gauged SL (2, R)/ U (1) WZW model, which has the black hold target space geometry, are considered. It is shown that the model has world-sheet instantons which give a nonzero contribution to the partition function. The question of the breakdown of the conformal invariance by instantons is studied. The answer depends on whether the topological term is introduced into the model or not.
CHIRAL PERTURBATION THEORY AT THE QUARK LEVEL AND NEW NONPERTURBATIVE FORMULAE FOR THE PION DECAY CONSTANT IN QCD
Authors: GOGOHIA V. SH.
Published: November 2004

Introducing the most general expression for the corresponding axial-vector vertex, the flavor nonsinglet, chiral axial-vector Ward-Takahashi (WT) identity is investigated in the framework of dynamical chiral symmetry breaking (DCSB). A chiral perturbation theory at the quark level (CHPTq) is proposed in terms of a Taylor series expansions in powers of the external momenta q (momentum of a massless pion) for the direct solution of the above identity at small momentum transfer q (momentum of a massless pion). Correct treatment of initial dynamical singularities at q=0 within the CHPTq approach in accordance with the Ball and Chiu procedure makes it possible to decompose the axial-vector vertex into pole and regular parts in a self-consistent way. The Bethe-Salpeter (BS) bound-state amplitude of a massless pion restored from the identity is shown to coincide with the residue at pole q2=0, which is proportional to the pion decay constant. We find exact solution for the regular piece of the corresponding vertex at zero momentum transfer in terms of the quark propagator dynamical variables alone. This solution automatically satisfies asymptotic freedom (it approaches the point-like vertex at infinity). Applying the proposed CHPTq approach to the matrix element of the axial-vector current determining the pion decay constant, we find “exact” (within the BS bound-state amplitude, restored fom the axial WT identity), nonperturbative expression for the pion decay constant in the current algebra (CA) representation. We show explicitly that the well-known formula of Pagels-Stokar-Cornwall for the pion decay constant is a particular case of the CHPTq approach. We find also new, nonperturbative formulae for the pion decay constant in the Jackiw-Johnson (JJ) representation as well. They now have full physical sense within the CHPTq approach. Renormalization of these expressions as well as their application in technicolor theories with slowly running couplings are briefly discussed. We also propose to distinguish between the scales of DCSB at the quark and hadronic levels (the scale of effective field theory) as well as advocate a simple relation between them based on naive counting arguments.
ON N = 4 INTEGRABLE MODELS
Authors: SAIDI E. H. , SEDRA M. B.
Published: November 2004

Using the FS and HST versions of the free N = 4 matter multiplet (O4, (1/2)4), we construct two N = 4 SU(2) conformal superfield models. The corresponding N = 4 conserved currents are given. We find that no N = 4 SU(2) Liouville model exists as long as the SU(2) KM symmetry is manifestly preserved. However allowing an explicit breaking of the SU(2) KM subsymmetry of the N = 4 conformal algebra down to U(1) KM, we obtain a Feigin–Fuchs extension of the N = 4 supercurrent showing that N = 4 Liouville theory and its Toda generalizations could exist. Quantization and the N = 4 conformal anomaly are studied.
MULTIPLE CHERN–SIMONS FIELDS ON A TORUS
Authors: WESOLOWSKI DENNE , HOSOTANI YUTAKA , HO CHOON-LIN
Published: November 2004

Intertwined multiple Chern–Simons gauge fields induce matrix statistics among particles. We analyze this theory on a torus, focusing on the vacuum structure and the Hilbert space. The theory can be mimicked, although not completely, by an effective theory with one Chern–Simons gauge field. The correspondence between the Wilson line integrals, vacuum degeneracy and wave functions for these two theories are discussed. Further, it is found in both of these cases that the two total momenta and Hamiltonian commute only in the physical Hilbert space.
FERMIONIC CHARACTER SUMS AND THE CORNER TRANSFER MATRIX
Authors: MELZER EZER
Published: November 2004

We present a "natural finitization" of the fermionic q-series (certain generalizations of the Rogers–Ramanujan sums) which were recently conjectured to be equal to Virasoro characters of the unitary minimal conformal field theory (CFT) ℳ (p, p + 1). Within the quasi-particle interpretation of the fermionic q-series this finitization amounts to introducing an ultraviolet cutoff, which — contrary to a lattice spacing — does not modify the linear dispersion relation. The resulting polynomials are conjectured (proven, for p = 3, 4) to be equal to corner transfer matrix (CTM) sums which arise in the computation of order parameters in regime III of the r = p + 1 RSOS model of Andrews, Baxter and Forrester. Following Schur's proof of the Rogers–Ramanujan identities, these authors have shown that the infinite lattice limit of the CTM sums gives what later became known as the Rocha–Caridi formula for the Virasoro characters. Thus we provide a proof of the fermionic q-series representation for the Virasoro characters for p = 4 (the case p = 3 is "trivial"), in addition to extending the remarkable connection between CFT and off-critical RSOS models. We also discuss finitizations of the CFT modular-invariant partition functions.
CHIRAL BOSON, CHIRAL VACUUM AND EDGE STATES IN THE FRACTIONAL QUANTUM HALL EFFECT
Authors: MYUNG YUN SOO
Published: November 2004

By performing the Gupta–Bleuler quantization of a chiral boson, we obtain the chiral constraints, which correspond to the lowest Landau level conditions. From these, the chiral vacuum is defined as the vacuum of admixtures of many-harmonic oscillators. We construct the wave function for edge states of a droplet of incompressible quantum Hall fluid, by solving Schrödinger's equation on the basis of the chiral vacuum. This bosonic function can describe the collective edge modes, which are fundamentally a many-body effect of fermions at the lowest Landau level. In detail, the neutral edge state of FQHE is described by the α = 1 chiral boson theory. The charged edge states are described by the α ≠ 1 chiral boson theory.
ANOMALIES AT FINITE TEMPERATURE AND DENSITY
Authors: GÓMEZ NICOLA A. , ALVAREZ-ESTRADA R. F.
Published: November 2004

Chiral anomalies for Abelian and non-Abelian quantum field theories at finite temperature and density (FTFD) are analyzed in detail in both imaginary and real time (IT and RT) formalisms. IT and RT triangle diagrams and IT functional methods (à la Fujikawa) are used at FTFD. The vector anomaly (the one regarding the lepton and baryon numbers) in the Weinberg–Salam theory, for an arbitrary number of fermion families, is also treated using IT functional methods at FTFD. In all cases, the expressions for the FTFD anomalies (as functions of the corresponding quantities) turn out to be identical to those at zero temperature and density, thereby extending previous results by various authors for the finite temperature and zero density case. Moreover, the independence of anomalies from temperature and density is shown to be consistent, at least in the Abelian case, with the analytic continuation from the IT formulation to the RT one.
KLEINIAN GEOMETRY AND THE N = 2 SUPERSTRING
Authors: BARRETT J. , GIBBONS G. W. , PERRY M. J. , POPE C. N. , RUBACK P.
Published: November 2004

This paper is devoted to the exploration of some of the geometrical issues raised by the N = 2 superstring. We begin by reviewing the reasons that β functions for the N = 2 superstring require it to live in a four-dimensional self-dual space–time of signature (− − + +), together with some of the arguments as to why the only degree of freedom in the theory is that described by the gravitational field. We move on to describe at length the geometry of flat space, and how a real version of twistor theory is relevant to it. We then describe some of the more complicated space–times that satisfy the β function equations. Finally we speculate on the deeper significance of some of these space–times.
ON THE BREMSSTRAHLUNG OF LOW AND HIGH ENERGY PHOTONS
Authors: ALVARADO J. J. , LUCIO M. J. L.
Published: November 2004

We analyze single photon bremsstrahlung of very low and very high energies. We point out a remarkable similarity between the two regimes.
HIGGS BOSON DISCOVERY POTENTIAL BEYOND THE MINIMAL STANDARD MODEL
Authors: SOPCZAK ANDRÉ
Published: November 2004

Detailed studies of neutral and charged Higgs boson pair production with full statistic detector simulations around [Formula: see text] with 500 pb−1 are presented in the context of a review of the Higgs boson discovery potential at LEP200. Already in the first phase of LEP200, a significant increase of the mass parameter space compared to LEP1 for the discovery of nonminimal Higgs bosons will be possible, while the mass range for the discovery of the minimal Standard Model Higgs boson will increase only marginally. The requirements for a decisive test of the Minimal Supersymmetric extension of the Standard Model (MSSM) at a later stage of LEP200 are discussed. A sensitivity mass range is given for charged Higgs bosons.
S MATRICES OF ϕ1,2-PERTURBED MINIMAL MODELS: IRF FORMULATION AND BOOTSTRAP PROGRAM
Authors: KOUBEK A.
Published: November 2004

We analyze the algebraic structure of ϕ1,2-perturbed minimal models, relating them to graph state models with an underlying Birman-Wenzl-Murakami algebra. Using this approach many physical properties of the IRF amplitudes can be derived, as the phase shifts in the ultraviolet limit, crossing relations and a simple formulation of the bootstrap equations. These are used to calculate explicitly the S matrix elements of higher kinks, and to determine the breather spectrum of the ϕ1,2 perturbations of the unitary minimal models ℳr,r+1. Finally it is checked that the bootstrap closes on those particles.
VARIATIONAL PERTURBATION THEORY
Authors: SISSAKIAN ALEXEY , SOLOVTSOV IGOR , SHEVCHENKO OLEG
Published: November 2004

A nonperturbative method — variational perturbation theory (VPT) — is discussed. A quantity we are interested in is represented by a series, a finite number of terms of which not only describe the region of small coupling constant but reproduce well the strong coupling limit. The method is formulated only in terms of the Gaussian quadratures, and diagrams of the conventional perturbation theory are used. Its efficiency is demonstrated for the quantum-mechanical anharmonic oscillator. The properties of convergence are studied for series in VPT for the [Formula: see text] model. It is shown that it is possible to choose variational additions such that they lead to convergent series for any values of the coupling constant. Upper and lower estimates for the quantities under investigation are considered.

The nonperturbative Gaussian effective potential is derived from a more general approach, VPT. Various versions of the variational procedure are explored and the preference for the anharmonic variational procedure in view of convergence of the obtained series is argued.

We investigate the renormalization procedure in the φ4 model in VPT. The nonperturbative β function is derived in the framework of the proposed approach. The obtained result is in agreement with four-loop approximation and has the asymptotic behavior as g3/2 for a large coupling constant.

We construct the VPT series for Yang-Mills theory and study its convergence properties. We introduce coupling to spinor fields and demonstrate that they do not influence the VPT series convergence properties.
FERMIONIC AND BOSONIC DETERMINANTS IN THE SEMIBOSONIZED NAMBU-JONA-LASINIO MODEL
Authors: BLOTZ ANDREE , GOEKE KLAUS
Published: November 2004

For the semibosonized SU(2) Nambu-Jona-Lasinio model an expansion of the classical action is made up to the second order in the fermionic and bosonic fluctuations. Integrating out both types of fluctuations and performing the Legendre transform one obtains an effective action with classical meson fields and classical, anticommuting fermion fields. An explicit form for the effective potential is derived as well as expressions for the renormalization of the coupling constants, fermion mass and wave functions. The effects on meson and quark masses and the effective potential is of order [Formula: see text] and numerically turn out to be small in the physical region of coupling constants. It is shown that one can obtain the contributions from exchange diagrams in four-fermion theories within the present path integral quantization. The results differ from investigations in the literature by the inclusion of wave function renormalization. The gradient expansion method, well known from fermion determinants, can be generalized such that it can be applied to bosonic determinants. If such an expansion is performed in the present case one can identify terms which also appear in the Weinberg Lagrangian. Nevertheless altogether the influence of the bosonic loop on the axial vector coupling constant gA of constituent quarks vanishes and we obtain the classical value gA=1. The contribution of the bosonic loop to the isosinglet axial vector current of the quarks is considered for the case of a U (2)R ⊗ U (2)L symmetry and is actually nonvanishing.
A PROPOSAL FOR A DIFFERENTIAL CALCULUS IN QUANTUM MECHANICS
Authors: GOZZI E. , REUTER M.
Published: November 2004

In this paper, using, the Weyl-Wigner-Moyal formalism for quantum mechanics, we develop a quantum-deformed exterior calculus on the phase space of an arbitrary Hamiltonian system. Introducing additional bosonic and fermionic coordinates, we construct a supermanifold which is closely related to the tangent and cotangent bundle over phase space. Scalar functions on the supermanifold become equivalent to differential forms on the standard phase space. The algebra of these functions is equipped with a Moyal superstar product which deforms the pointwise product of the classical tensor calculus. We use the Moyal bracket algebra to derive a set of quantum-deformed rules for the exterior derivative, Lie derivative, contraction, and similar operations of the Cartan calculus.
A UNIFIED FORMALISM OF THERMAL QUANTUM FIELD THEORY
Authors: CHU H. , UMEZAWA H.
Published: November 2004

We present a comprehensive review of the most fundamental and practical aspects of thermo-field dynamics (TFD), including some of the most recent developments in the field. To make TFD fully consistent, some suitable changes in the structure of the thermal doublets and the Bogoliubov transformation matrices have been made. A close comparison between TFD and the Schwinger-Keldysh closed time path formalism (SKF) is presented. We find that TFD and SKF are in many ways the same in form; in particular, the two approaches are identical in stationary situations. However, TFD and SKF are quite different in time-dependent nonequilibrium situations. The main source of this difference is that the time evolution of the density matrix itself is ignored in SKF while in TFD it is replaced by a time-dependent Bogoliubov transformation. In this sense TFD is a better candidate for time-dependent quantum field theory. Even in equilibrium situations, TFD has some remarkable advantages over the Matsubara approach and SKF, the most notable being the Feynman diagram recipes, which we will present. We will show that the calculations of two-point functions are simplified, instead of being complicated, by the matrix nature of the formalism. We will present some explicit calculations using TFD, including space-time inhomogeneous situations and the vacuum polarization in equilibrium relativistic QED.
NEAR FUTURE PROSPECTS OF QCD SPIN STUDIES
Authors: NADOLSKY P.M. , TROSHIN S.M. , TYURIN N.E.
Published: November 2004

We consider the physics motivations and prospects for the study of spin phenomena at future high energy accelerators. The possibilities of using the already operating machines are also discussed. It is emphasized that the present status of QCD spin studies requires a wide range of spin measurements.
NONCLASSICAL ANALOGIES OF CLASSICAL SOLITON SOLUTIONS
Authors: SVESHNIKOV K.A.
Published: November 2004

We discuss the possible existence of a series of nonclassical analogies of classical soliton solutions, which do not exist when the effective Planck constant of the theory γ tends to zero. Within the conventional weak-coupling expansion in [Formula: see text], such nonclassical configurations are [Formula: see text] in energy and therefore lie between the true classical solutions and true secondary quantized excitations. The analytic results concerning the shape functions, masses and stability properties of such excitations are given for φ4-kink theory.
NEW SETS OF KINK-BEARING HAMILTONIANS
Authors: DEY B. , KUMAR C.N.
Published: November 2004

Given a kink-bearing Hamiltonian, the isospectral Hamiltonian approach is used in generating new sets of Hamiltonians which also admit kink solutions. We use the sine-Gordon model as an example and explicitly work out new sets of potentials and solutions.
A UNIFIED SCHEME FOR MODULAR INVARIANT PARTITION FUNCTIONS OF WZW MODELS
Authors: ABOLHASSANI M.R. , ARDALAN F.
Published: November 2004

We introduce a unified method which can be applied to any WZW model at arbitrary level to search systematically for modular invariant physical partition functions. Our method is based essentially on modding out a known theory on group manifold G by a discrete group Γ. We apply our method to [Formula: see text] with n=2, 3, 4, 5, 6, and to [Formula: see text] models, and obtain all the known partition functions and some new ones, and give explicit expressions for all of them.
TO THE TOPOLOGY OF KRAMERS-WANNIER DUALITY
Authors: MISIRPASHAEV T. SH.
Published: November 2004

We show that for an even-dimensional hypercubic lattice one can modify the construction of a dual lattice to have the correspondence edge-edge instead of the conventional correspondence edge-(d−1)-dimensional face. This gives a straightforward generalization of Kramers-Wannier duality for an even-dimensional Ising model. In the same way as the partition function for the 2D Ising model is related to a sum over paths on a torus, higher-dimensional models involve sums over paths on Riemannian surfaces of higher genus. The critical temperature can be located only in the d=2 case in which all topological effects disappear from the thermodynamic limit. The duality in higher dimensions, however, being weak, leads nevertheless to some interesting relations for sums over paths on Riemannian surfaces, which can be considered as a topological characteristic of a critical point.
QUADRATIC DIVERGENCES IN GUTS WITH VANISHING ONE-LOOP BETA FUNCTIONS
Authors: LUCHA WOLFGANG , MOSER MICHAEL
Published: November 2004

All members of a recently proposed new set of (nonsupersymmetric) grand unified theories with one-loop-level vanishing beta functions for the gauge, Yukawa, and scalar-boson self-interaction coupling constants are shown to involve, already at the one-loop level, quadratically divergent contributions to both the vector-boson and scalar-boson masses.
NONSTANDARD MODEL COUPLINGS IN WWV VERTEX
Authors: RASHID A.M. HARUN AR , ISLAM KH. SAIFUL
Published: November 2004

Using the nonstandard model vertex for WWV coupling, the helicity amplitudes, differential cross-sections and total cross-sections for the process e+e−→W+W− as functions of κV and λV have been calculated, and compared with SM predictions. A similar calculation has also been done for the process eγ→Wνe.
ALE MANIFOLDS AND CONFORMAL FIELD THEORIES
Authors: ANSELMI DAMIANO , BILLÓ MARCO , FRÉ PIETRO , ZAFFARONI ALBERTO , GIRARDELLO LUCIANO
Published: November 2004

We address the problem of constructing the family of (4,4) theories associated with the σ model on a parametrized family ℳζ of asymptotically locally Euclidean (ALE) manifolds. We rely on the ADE classification of these manifolds and on their construction as hyper-Kähler quotients, due to Kronheimer. By so doing we are able to define the family of (4,4) theories corresponding to a ℳζ family of ALE manifolds as the deformation of a solvable orbifold C2/Γ conformal field theory, Γ being a Kleinian group. We discuss the relation between the algebraic structure underlying the topological and metric properties of self-dual four-manifolds and the algebraic properties of nonrational (4,4) theories admitting an infinite spectrum of primary fields. In particular, we identify the Hirzebruch signature τ with the dimension of the local polynomial ring [Formula: see text] associated with the ADE singularity, with the number of nontrivial conjugacy classes in the corresponding Kleinian group and with the number of short representations of the (4,4) theory minus four.
CANONICAL QUANTIZATION OF TWO-DIMENSIONAL GAUGE FIELDS
Authors: HETRICK JAMES E.
Published: November 2004

SU (N) gauge fields on a cylindrical space-time are canonically quantized via two routes revealing almost equivalent but different quantizations. After removal of all continuous gauge degrees of freedom, the canonical coordinate Aµ (in the Cartan subalgebra [Formula: see text]) is quantized. The compact route, as in lattice gauge theory, quantizes the Wilson loop W, projecting out gauge-invariant wave functions on the group manifold G. After a Casimir energy related to the curvature of SU (N) is added to the compact spectrum, it is seen to be a subset of the noncompact spectrum. States of the two quantizations with corresponding energy are shifted relative to each other, such that the ground state on G, χ0(W), is the first excited state Ψ1(Aµ) on [Formula: see text]. The ground state Ψ0(Aµ) does not appear in the character spectrum, as its lift is not globally defined on G. Implications for lattice gauge theory and the sum-over-maps representation of two-dimensional QCD are discussed.
MAXWELL-CHERN-SIMONS ELECTRODYNAMICS ON A DISK
Authors: BALACHANDRAN A.P. , CHANDAR L. , ERCOLESSI E. , GOVINDARAJAN T.R. , SHANKAR R.
Published: November 2004

The Maxwell-Chern-Simons (MCS) Lagrangian is the Maxwell Lagrangian augmented by the Chern-Simons term. In this paper, we study the MCS and Maxwell Lagrangians on a disk D. They are of interest for the quantum Hall effect, and also when the disk and its exterior are composed of different media. We show that quantization is not unique, but depends on a nonnegative parameter λ. 1/λ is the penetration depth of the fields described by these Lagrangians into the medium in the exterior of D. For λ=0, there are edge observables and edge states localized at the boundary ∂D for the MCS system. They describe the affine Lie group [Formula: see text]. Their excitations carry zero energy, signifying an infinite degeneracy of all states of the theory. There is also an additional infinity of single particle excitations of exactly the same energy proportional to |k|, k being the strength of the Chern-Simons term. The MCS theory for λ=0 has the huge symmetry group [Formula: see text]. In the Maxwell theory, the last-mentioned excitations are absent while the edge observables, which exist for λ=0, commute. Also, these excitations are described by states which are not localized at ∂D and are characterized by a continuous and infinitely degenerate spectrum. All these degeneracies are lifted and edge observables and their states cease to exist for λ>0.

The novel excitations discovered in this paper should be accessible to observations. We will discuss issues related to observations, as also the generalization of the present considerations to vortices, domain walls and monopoles, in a paper under preparation.
CONSERVATION LAWS AND GEOMETRY OF PERTURBED COSET MODELS
Authors: BAKAS IOANNIS
Published: November 2004

We present a Lagrangian description of the SU(2)/U(1) coset model perturbed by its first thermal operator. This is the simplest perturbation that changes sign under Krammers-Wannier duality. The resulting theory, which is a two-component generalization of the sine-Gordon model, is then taken in Minkowski space. For negative values of the coupling constant g, it is classically equivalent to the O(4) nonlinear σ model reduced in a certain frame. For g>0, it describes the relativistic motion of vortices in a constant external field. Viewing the classical equations of motion as a zero curvature condition, we obtain recursive relations for the infinitely many conservation laws by the abelianization method of gauge connections. The higher spin currents are constructed entirely using an off-critical generalization of the W∞ generators. We give a geometric interpretation to the corresponding charges in terms of embeddings. Applications to the chirally invariant U(2) Gross-Neveu model are also discussed.
FINITE CHAINS WITH QUANTUM AFFINE SYMMETRIES
Authors: ALCARAZ F.C. , ARNAUDON D. , RITTENBERG V. , SCHEUNERT M.
Published: November 2004

We consider an extension of the t-U Hubbard model taking into account new interactions between the numbers of up and down electrons. We confine ourselves to a one-dimensional open chain with L sites (4L states) and derive the effective Hamiltonian in the strong repulsion (large U) regime. This Hamiltonian acts on 3L states. We show that the spectrum of the latter Hamiltonian (not the degeneracies) coincides with the spectrum of the anisotropic Heisenberg chain (XX Z model) in the presence of a Z field (2L states). The wave functions of the 3L-state system are obtained explicitly from those of the 2L-state system, and the degeneracies can be understood in terms of irreducible representations of [Formula: see text].
THERMAL PROPERTIES AND GROUND STATE ENERGY SHIFT OF CHARGED ANYONS
Authors: KIM J.Y. , MYUNG Y.S. , YI S.H.
Published: November 2004

We derive the second and third virial coefficients and the ground state energy shift for charged anyons within the Hartree-Fock approximation. A second quantization scheme at finite temperature is introduced for this calculation up to the second order and the vertex is composed of anyonic, point, constant as well as Coulomb interactions. The thermodynamic potential for the second order correlation diagram of Coulomb interaction leads to the logarithmic divergence (V ln V). Hence, we find the heat capacity and the correlation energy of anyons without Coulomb-Coulomb interaction. Finally, we discuss the magnetic-field-induced localization at low filling ν, including the Wigner crystal phase.
BOUNDARY S MATRIX AND BOUNDARY STATE IN TWO-DIMENSIONAL INTEGRABLE QUANTUM FIELD THEORY
Authors: GHOSHAL SUBIR , ZAMOLODCHIKOV ALEXANDER
Published: November 2004

We study integrals of motion and factorizable S matrices in two-dimensional integrable field theory with boundary. We propose the "boundary cross-unitarity equation," which is the boundary analog of the crossing-symmetry condition of the "bulk" S matrix. We derive the boundary S matrices for the Ising field theory with boundary magnetic field and for the boundary sine–Gordon model.
QUANTUM LOOP MODULES AND QUANTUM SPIN CHAINS
Authors: ALTSCHULER DANIEL , DAVIES BRIAN
Published: November 2004

We construct level-0 modules of the quantum affine algebra [Formula: see text], as the q-deformed version of the Lie algebra loop module construction. We give necessary and sufficient conditions for the modules to be irreducible. We construct the crystal base for some of these modules and find significant differences from the case of highest weight modules. We also consider the role of loop modules in the recent scheme for diagonalizing certain quantum spin chains using their [Formula: see text] symmetry.
FACTORIZATION AND DISCRETE STATES IN $\hat c =1$ SUPER-LIOUVILLE THEORY
Authors: ALDAZABAL G. , BONINI M. , MALDACENA J. M.
Published: November 2004

Factorization properties of scattering amplitudes are used to study the discrete state structure of [Formula: see text] superconformal matter coupled to 2D supergravity theory. Vertex operators are explicitly constructed and possible gauge transformations analyzed. The fitting of these states into SU(2) multiplets is briefly discussed. The algebra generated by both Neveu–Schwarz and Ramond states is considered in the limit of null cosmological constant.
THE q-DEFORMED SCHRÖDINGER EQUATION OF THE HARMONIC OSCILLATOR ON THE QUANTUM EUCLIDEAN SPACE
Authors: CAROW-WATAMURA URSULA , WATAMURA SATOSHI
Published: November 2004

We consider the q-deformed Schrödinger equation of the harmonic oscillator on the N-dimensional quantum Euclidean space. The creation and annihilation operators are found, which systematically produce all energy levels and eigenfunctions of the Schrödinger equation. In order to get the q series representation of the eigenfunction, we also give an alternative way to solve the Schrödinger equation which is based on the q analysis. We represent the Schrödinger equation by the q difference equation and solve it by using q polynomials and q exponential functions.
THREE-DIMENSIONAL FIELD THEORIES FROM INFINITE-DIMENSIONAL LIE ALGEBRAS
Authors: PERRET R. E. C.
Published: November 2004

A procedure for constructing topological actions from centrally extended Lie algebras is introduced. For a Kac–Moody algebra, this produces the three-dimensional Chern–Simons theory, while for the Virasoro algebra, the result is a new three-dimensional topological field theory whose physical states satisfy the Virasoro Ward identity. This topological field theory is shown to be a first order formulation of two-dimensional induced gravity in the chiral gauge. The extension to W3 gravity is discussed.
PHASE TRANSITION IN RIGID QED
Authors: AWADA MOUSTAFA , ZOLLER DAVID
Published: November 2004

We present a new model of QED which exhibits two distinct phases. The model emerges in the first-quantized formalism where it is possible to generalize QED by adding the curvature of the world line to the usual kinetic term, the arc length action of the point particle. The Boltzmann factor associated with the curvature term favors rigid paths. The curvature term is not only scale-invariant and hence renormalizable but it is also the unique reparametrization-invariant term with second derivatives with this property. The new term transforms a single electron of mass m into an infinite number of particles with masses varying inversely with the spin (Majorana mass spectrum). The value of the bare curvature coupling determines which phase the theory is in. For bare curvature coupling α0 less than a certain critical coupling αc, we recover conventional QED as one phase where the curvature term is absent at large distance scales in the continuum theory. For α0 greater than αc, we have a new phase characterized by a curvature law. Using mean field theory methods, we determine αc to be of the order of one. We argue that the positronium spectrum in the strong curvature phase is approximately described by a Majorana mass formula. Even though the GSI experiments might not survive further experimental tests, we nevertheless examine the Majorana spectrum with the three observed narrow e+ e− peaks observed in the GSI experiments and make some possible new predictions.
HIGHER ORDER EQUATIONS AND CONSTITUENT FIELDS
Authors: BARCI D. G. , BOLLINI C. G. , OXMAN L. E. , ROCCA M.
Published: November 2004

We consider a simple wave equation of fourth degree in the D'Alembertian operator. It contains the main ingredients of a general Lorentz-invariant higher order equation, namely, a normal bradyonic sector, a tachyonic state and a pair of complex conjugate modes. The propagators are respectively the Feynman causal function and three Wheeler-Green functions (half-advanced and half-retarded). The latter are Lorentz-invariant and consistent with the elimination of tachyons and complex modes from free asymptotic states. We also verify the absence of absorptive parts from convolutions involving Wheeler propagators.
HUNTING FOR SUPERSYMMETRY IN INTENSE ELECTROMAGNETIC FIELDS
Authors: KURILIN ALEXANDER V.
Published: November 2004

We calculate the probabilities of slepton and photino production via a charged lepton decay induced by an arbitrary electromagnetic wave or by a constant homogeneous external field, Fμν. This allows us to estimate the domains where this reaction could be significant. Comparing the process [Formula: see text] with the synchrotron radiation we conclude that for all values of the background field parameter [Formula: see text], with pν being the lepton’s momentum, the following estimate holds: [Formula: see text].

We also study the impact of the intense field on radiative corrections to the lepton’s anomalous magnetic moment. It is found that, when χ exceeds the cube of the masses’ ratios, [Formula: see text], [Formula: see text], the sparticle’s contribution to the anomalous magnetic moment is of the same order as the QED correction. In this region the magnitude of the anomalous magnetic moment of the lepton is very sensitive to the masses of the slepton and the photino.
INDUCED B∧F TERM AND PHOTON MASS GENERATION IN 3+1 DIMENSIONS
Authors: LEBLANC M. , MACKENZIE R. , PANIGRAHI P.K. , RAY R.
Published: November 2004

Analyzing a (3+1)-dimensional model with four-fermi interactions, we show that topological B∧F terms (both Abelian and non-Abelian) can be induced radiatively by massive fermions at the one-loop level. It is further pointed out that a mechanism of photon (or non-Abelian gauge field) mass generation distinct from the usual Higgs mechanism, through the B∧F term, is also implemented in the long distance effective action of this model, provided a gap equation is satisfied.
A NEW GEOMETRIC SETTING FOR LAX EQUATIONS
Authors: CARIÑENA J.F. , MARTÍNEZ E.
Published: November 2004

We show the existence of Lax equations which does not correspond to the vanishing of the Lie or covariant derivative of a (1, 1) type tensor field with respect to a vector field, but they have a different origin, and we provide a more general setting for this kind of equations.
OBTAINING DYNAMICAL GROUPS AND QUANTUM DEGREES OF FREEDOM BY USING NOETHER’S THEOREM: THE PLANAR LANDAU SYSTEM
Authors: SIMÕES TIAGO J.M.
Published: November 2004

The noncompact quantum dynamical group SU(2, 1) and the associated su(2, 1) spectrum-generating algebra of the nonrelativistic planar Landau system are constructively obtained from the classical theory, by considering time-dependent Noether symmetry transformations and along the lines of a procedure recently proposed by Castaños, Frank and López-Peña. For this nonconstrained system in the circular gauge, we have found an explicitly time-dependent Hermitian invariant operator, which is crucial for the correct identification of the number of quantum degrees of freedom.
PREDICTIONS FOR NON-ABELIAN FINE STRUCTURE CONSTANTS FROM MULTIPLE POINT CRITICALITY
Authors: BENNETT D.L. , NIELSEN H.B.
Published: November 2004

In developing a model for predicting the non-Abelian gauge coupling constants, we argue for the phenomenological validity of a “principle of multiple point criticality.” This is supplemented with the assumption of an “(grand) antiunified” gauge group SMG N gen ~ U(1) N gen × SU(2) N gen × SU(3) N gen which, at the Planck scale, breaks down to the diagonal subgroup. (Ngen is the number of generations, which is assumed to be three.) According to this principle of multiple point criticality, the Planck scale experimental couplings correspond to multiple point couplings of the bulk phase transition of a lattice gauge theory (with SMG N gen ). Predictions from this principle agree with running non-Abelian couplings (after an extrapolation to the Planck scale using the assumption of a “desert”) to an accuracy of 7%. As an explanation for the existence of the multiple point, a speculative model using a glassy lattice gauge theory is presented.
FUNCTIONAL RELATIONS IN SOLVABLE LATTICE MODELS II: APPLICATIONS
Authors: KUNIBA ATSUO , NAKANISHI TOMOKI , SUZUKI JUNJI
Published: November 2004

Reported are two applications of the functional relations (T system) among a commuting family of row-to-row transfer matrices proposed in the previous paper (Part I). For a general simple Lie algebra Xr, we determine the correlation lengths of the associated massive vertex models in the antiferroelectric regime and central charges of the RSOS models in two critical regimes. The results reproduce known values or even generalize them, demonstrating the efficiency of the T system.
TWO- AND THREE-VECTOR-BOSON PRODUCTION IN e+e- COLLISIONS WITHIN THE BESS MODEL
Authors: CVETIČ G. , GROSSE-KNETTER C. , KÖGERLER R.
Published: November 2004

The BESS model is the Higgsless alternative to the standard model of electroweak interaction with nonlinear realized spontaneous symmetry breaking. Since it is nonrenormalizable, new couplings (not existing in the SM) are induced at each loop order. On the basis of the one-loop induced gauge boson self-couplings we calculated the cross sections for the two- and three-gauge-boson production processes in e+e- collisions. Measurements of these cross sections in a planned e+e- linear collider at [Formula: see text] (NLC) will supply a good empirical test of the gauge boson self-interactions and thus should enable us to discriminate between the SM and the BESS model.
SYMPLECTIC QUANTIZATION OF SUPERFIELDS
Authors: BARCELOS-NETO J. , CHEB-TERRAB E.S.
Published: November 2004

We show how the extension of the Faddeev-Jackiw symplectic quantization (including true constraints) can be used in superspace. We first deal with supersymmetric free field theory in the component language. After that, we consider the method applied to superfields, taken as canonical variables. We also use the formalism, directly in superfield formulation, for the supersymmetric nonlinear sigma model.
A VARIATIONAL BETHE-ANSATZ APPROACH TO THE HEISENBERG ANTIFERROMAGNET AT NON-ZERO FIELD
Authors: MONTENEGRO M. , GOTTLIEB D. , MEDEIROS DJALMA , CABRERA G. G.
Published: November 2004

The antiferromagnetic Heisenberg chain with axial anisotropy and applied magnetic field parallel to the axis, is probed through a new variational approach based on the Bethe–Ansatz solution at zero field. The variational ket is built by rotating the spins in the Bethe solution, with the angles and the value of the local magnetic moment as variational parameters. This procedure allows for a description of the various magnetic phases in the presence of a parallel field, such as ferromagnetic (F), antiferromagnetic (AF), and spin-flop (SF) phases. The approximation reduces to the exact Bethe solution for vanishing field. We compare with exact numerical results (Lanczos calculations for finite systems), and exact solutions when available.
A CONDENSED MATTER ANALOG OF QCD WITH QUARKS
Authors: SHANKAR R.
Published: November 2004

It is well known that the d = 1 + 1 nonlinear sigma model is a remarkable analog of pure Yang-Mills theory in d = 3 + 1 and that the former in turn arises in the study of Quantum Spin Chains. It is shown that, upon doping with holes, the chain is described by a fully relativistic theory of Dirac fermions coupled to the sigma model by a gauge interaction. The theory is seen to mimic QCD with quarks in many remarkable ways.
The Conjugate Electromagnetic Properties of Bosons and Vortices in Two-dimensions
Authors: Lee Dung-Hai
Published: November 2004

The electromagnetic properties of bosons and vortices are conjugate to each other. In this paper we demonstrate this duality using several different "states of matter" in two dimensions.
A SINGLE HOLE IN THE TWO-DIMENSIONAL INFINITE-U HUBBARD MODEL IN AN ORBITAL MAGNETIC FIELD
Authors: MESHKOV S. V. , ANGLÈS D'AURIAC J. C.
Published: November 2004

Using an original Quantum Monte Carlo algorithm, we study the thermodynamical properties of a single hole in the two-dimensional infinite-U Hubbard model at finite temperature. We investigate the energy and the spin correlators as a function of an external orbital magnetic field. This field is found to destroy the Nagaoka ferromagnetism and to induce chirality in the spin background. The applied field is partially screened by a fictitious magnetic field coming from the chirality. Our algorithm allows us to reach a temperature low enough to discuss the ground state properties of the model.
HOPPING CONDUCTION IN POLYMERS
Authors: Bässler Heinz
Published: November 2004

The concept of hopping within a Gaussian density of localized states introduced earlier to rationalize charge transport in random organic photoconductors is developed further to account for temporal features of time of flight (TOF) signals. At moderate degree of energetic disorder (σ/kT~3.5…4.5) there is a transport regime intermediate between dispersive and quasi-Gaussian type whose signatures are (i) universal TOF signals that can appear weakly dispersive despite yielding a well defined carrier mobility and (ii) an asymmetric propagator of the carrier packet yielding a time dependent diffusivity.
LOW ENERGY EXCITATIONS AND NON-ERGODICITY IN THE COULOMB GLASS
Authors: Ortuño M. , Pollak M. , Talamantes J.
Published: November 2004

Recent computational methods permit the determination of the low energy states of fair sized systems of localized interacting particles in random media. Making use of such methods, this paper evaluates the nature of the low-energy excitations of the system, and it’s implications on conductivity and on ergodicity. Two- and three-dimensional systems are examined. It is found that the low energy excitations exhibit strong correlation effects, indicating that one-particle theories for equilibrium and non-equilibrium properties are not justified. Ergodicity is tested by relaxation at zero temperature. It is found that relaxation time can be extremely long, indicating that the system is not ergodic at low temperatures.
NONLINEAR TRANSPORT IN HYDROGEN-BONDED CHAINS: SOLITONS UNDER EXTERNAL FIELDS AND DAMPING
Authors: KIVSHAR YU.S. , SAVIN A.V. , VELGAKIS M.J. , ZOLOTARYUK A.V.
Published: November 2004

The longitudinal dynamics of protons in hydrogen-bonded chains is studied in the framework of a simple one-component one-dimensional model with a two-parameter doubly periodic symmetric on-site potential proposed by Zolotaryuk and Pnevmatikos (1990) under an external electric field and damping. The behavior of the ionic and bonding defects has been proved analytically and numerically to exhibit particle-like properties. Mobilities of the dc and ac driven defects have also been calculated with different methods. Small-amplitude oscillating solutions of breather and envelope solitons have been studied analytically and numerically.
THE LINEAR RESPONSE APPROACH TO THE FOKKER-PLANCK EQUATION III: A DETERMINISTIC AND CHAOTIC BOOSTER
Authors: BIANUCCI MARCO , MANNELLA RICCARDO , GRIGOLINI PAOLO , WEST BRUCE J.
Published: November 2004

We apply the theory developed in I1 to two deterministic nonlinear systems with few degrees of freedom (mappings). The first mapping considered is known to exactly satisfy the prescriptions laid down in I to obtain the Fokker-Planck equation associated to Brownian motion. For the second mapping, due to its more complex form, it is not possible to prove analytically that it too satisfies the prescriptions of I; however, we show numerically that this fact is plausible, at least in the chaotic regime. For both cases we show that indeed Brownian motion for the variable of interest w arises. We conclude arguing that the theory developped in I is generally applicable to systems for which the “thermal bath” is in a fully chaotic state.
QUASIPROBABILITY DISTRIBUTIONS FOR THE THREE-LEVEL JAYNES-CUMMINGS MODEL
Authors: HUYEN NGUYEN DINH , DUNG HO TRUNG
Published: November 2004

The Q-function and Wigner function for a three-level system coupled to a one-mode coherent field under two-photon resonance are treated for various initial atomic states. It is shown that the dynamical behavior of the quasiprobability distributions reflects the collapses and revivals in the time histories of the Rabi oscillations in a very interesting way. The structured quasiprobabilities are reviewed in the light of the semiclassical eigenstates.
EFFECTIVE FIELD THEORY OF SINGLE AND MULTILAYERED QUANTUM HALL FLUIDS
Authors: GELLER MICHAEL R.
Published: November 2004

We review an effective field theory of the quantum Hall fluid, where electron currents are expressed in terms of multiple-component gauge fields, and develop further the case of two-component fields. The form of the effective action, a simple matrix Chern-Simons action, is dictated by the principles of current conservation, dimensional analysis, gauge invariance, and by the presence of a gap. The formalism naturally describes multiple-component systems such as coupled Hall fluids in layered geometries, in addition to describing more complicated single-fluid states. We provide a complete classification of fractional quantum Hall states describable by two-component Chern-Simons gauge fields.