bluuebunny/crossref_metadata_2025 huggingface dataset:
Monte-Carlo Simulation Artefacts in Physical Modeling due to Pseudo-Random Generators
Authors: BERDNICOV A.S. , TURTIA S.B.
Published: November 2004

A set of vector algorithms for random vectors generation is tested by the authors. Only the most reliable algorithms are selected for testing. The special system of original tests is developed with the main criteria of the independence of random vector components and the equability of N-dimensional hypercube filling. Some algorithms are discovered to be bad for physical modeling, and for others recommendations for their use for different physical problems are given.
Calculated Optical Properties of the Anisotropic Transition Metals
Authors: KRASOVSKII E.E. , ANTONOV V.N.
Published: November 2004

The optical properties of Sc, Ti, Y, Zr, Tc and Ru are studied theoretically. The dielectric functions of metals are calculated ab initio in the framework of self-consistent one-electron theory. The Schrödinger equation for the Bloch functions is solved numerically using the linear augmented plane wave (LAPW) method. The momentum matrix elements are computed directly from the LAPW wave functions. On the basis of the calculated energy band structure the optical constants (dielectric functions, optical conductivity, reflectivity, energy loss function) were determined.

The theoretically obtained spectra are compared with experimental data. The calculated curves have been found to describe all the main features of the anisotropy of optical spectra. The origin of all the structures is elucidated. The reason for the significant anisotropy of the infra-red reflectivity is discussed.
Internal Location of a Point in a Nonconvex Polygon in 3D
Authors: NICULESCU V.I.R. , CAVALERU A.O.R.
Published: November 2004

A subroutine is described that decides if a test point is located inside a domain enclosed by a nonconvex polygon from E3 (3D).
Molecular Force Field Calculations on Large Computers
Authors: SUNDIUS T.
Published: November 2004

A program for molecular force field calculations (MOLVIB) has been implemented on a CRAY X-MP computer, in order to test its performance for large molecules. Convergence tests were also performed with large sets of molecules to study how variations in the initial force constants affect the final force field.
Intermediate Effective Operators in Valence-Bond Model Spaces
Authors: ZAITSEVSKII A.V. , DEMENT’EV A.I.
Published: November 2004

We developed and implemented an algorithm of ab initio intermediate effective operator construction for model spaces spanned by valence-bond-like configuration state functions built from orthogonalized atomic orbitals.
CONVERGENCE TIME ON THE RS MODEL FOR NEURAL NETWORKS
Authors: PENNA T.J.P. , de OLIVEIRA P.M.C. , ARENZON J.J. , de ALMEIDA R.M.C. , IGLESIAS J.R.
Published: November 2004

Convergence times and the corresponding dispersions have been studied numerically as parameters to measure the efficiency of neural network models. These quantities are also supposed to be related to the number of spurious states for each configuration of stored patterns. In this work we measure these quantities for a recent multineuron interaction model presenting an enhanced performance compared to other traditional schemes.
SIMULATIONS OF KINETIC ROUGHENING WITH POWER-LAW NOISE ON THE CONNECTION MACHINE
Authors: BOURBONNAIS R. , HERRMANN H.J. , VICSEK T.
Published: November 2004

We present results of large scale simulations on the Connection Machine (CM) on the scaling behavior of the Zhang model and its variants for the kinetics of self-affine interfaces with power-law noise. Details on implementing this problem on a massively parallel computer such as the CM are given. Our calculations for the case when the amplitude η of the noise has a distribution P(η)~η−1−µ are in good agreement with earlier findings of non-universality for µ<7. We present data which suggest that for µ≥7 the model is in the universality class of Gaussian noise.
MONTE CARLO DIAGONALIZATION OF VERY LARGE MATRICES: APPLICATION TO FERMION SYSTEMS
Authors: RAEDT H. DE , LINDEN W. VON DER
Published: November 2004

All known Quantum-Monte-Carlo algorithms for fermions suffer from the so-called “minus-sign-problem” which is detrimental to the application of these simulation methods to fermion systems at very low temperatures and/or of very many lattice sites. We identify the origin of this fundamental problem, demonstrate that it is a very general feature, not necessarily related to the presence of fermionic degrees of freedom. We describe an novel algorithm which does not suffer from the minus-sign problem. Illustrative results for the two-dimensional Hubbard model are presented
Q2R+Q2R AS A UNIVERSAL BILLIARD
Authors: CORDERO PATRICIO , GOLES ERIC , HERNANDEZ GONZALO
Published: November 2004

In this work we study the computing capabilities as well as some dynamical properties of an automaton called M4R. This automaton corresponds to the mixing of the energy profiles of two independent copies of the Q2R automaton with frustrations. We associate to each copy of a Q2R an equivalent automaton M2R, which, with the Margoluos neighborhood, exhibits the local changes of the Q2R energy.1 By doing so we generalize the dynamics by upgrading M2R according to four partitions of the lattice. This new dynamics — called M4R — is based on a local rule which corresponds to the local energy change of two independent copies of Q2R.

The M4R model is reversible and conservative (magnetization is constant in time) and it has properties of a discrete billiard (as some of the hydrodynamics discrete versions of Navier-Stokes models).

Moreover, this automaton has powerful computing capabilities. In fact, by using some special configurations of M4R, we exhibit universal gates and register that allow us to code any algorithm.
FINITE-SIZE SCALING AT CRITICAL POINTS WITH SPATIAL ANISOTROPIES
Authors: LEUNG KWAN-TAI
Published: November 2004

We report some selected recent developments in the finite-size scaling theory of critical phenomena occurring in systems with strong spatial anisotropies. Such systems are characterized by correlation lengths divergent with different exponents (ν⊥, ν||) along different directions. Attention is focused on the driven diffusive lattice gas that exhibits a second order nonequilibrium phase transition. We present in detail the phenomenology and its comparison with computer simulation. Novel features of finite-size effects in anisotropic nonequilibrium systems are emphasized.
CELLULAR-AUTOMATON-CONTROLLED LOGISTIC MAP: AN UNUSUAL TYPE OF NOISE
Authors: STARIOLO DANIEL A. , TSALLIS CONSTANTINO
Published: November 2004

We present a numerical study of the logistic map dynamics with time dependent parameter values whose evolution is in turn governed by a deterministic cellular automaton. We find an unusual type of noise which presents a surprising internal structure yielding a multiple band attractor.
FEIGENBAUM’S CONSTANT FOR MEROMORPHIC FUNCTIONS
Authors: GALLAS JASON A.C.
Published: November 2004

We calculate Feigenbaum’s constant for a double-periodic meromorphic function: the Jacobian elliptic function sn[2K (m)x, m].

For m=0 this function reduces to sin(πx), with real period, while for m=1 it reduces to a hyperbolic tangent, having a pure imaginary period. For intermediary m values it is unimodal but with a non-quadratic m-dependent maximum. The bifurcation tree for sn[2K(m)x, m], although very much compressed in [0, 1], presents δ=4.699… for all values of m.
INTERFACES AND THE QUARK HADRON PHASE TRANSITION
Authors: KAJANTIE K.
Published: November 2004

The tension of the interface between the high and low temperature phases of finite temperature Quantum Chromodynamics is an important characteristic of the quarkhadron phase transition. We discuss its cosmological effects and its determination, for planar and spherical interfaces, with lattice Monte Carlo techniques for the case of pure glue, Nt=2 SU(3) gauge theory.
CHIRAL PHASE TRANSITION IN HIGH TEMPERATURE QCD WITH MASSIVE QUARKS
Authors: BARBOUR I.M. , BELL A.J. , KLEPFISH E.G.
Published: November 2004

The thermal phase transition in lattice QCD at finite quark mass is studied from the distribution of the zeros of the partition function in the complex quark mass plane. Results from simulations at strong and intermediate coupling are presented. Evidence for a chirally related transition at non-zero quark mass in the intermediate coupling region for β<5.2. The method exhibits remarkable stability in the evaluation of the critical mass as the lattice volume increases. Conclusions regarding the possible phase structure of QCD in the mass-temperature plane are discussed.
ON THE TWO-POINT CORRELATION FUNCTION IN DYNAMICAL SCALING AND SCHRÖDINGER INVARIANCE
Authors: HENKEL MALTE
Published: November 2004

The extension of dynamical scaling to local, space-time dependent rescaling factors is investigated. For a dynamical exponent z=2, the corresponding invariance group is the Schrödinger group. Schrödinger invariance is shown to determine completely the two-point correlation function. The result is checked in two exactly solvable models.
MONTE CARLO METHODS FOR FIRST ORDER PHASE TRANSITIONS: SOME RECENT PROGRESS
Authors: BINDER KURT , VOLLMAYR KATHARINA , DEUTSCH HANS-PETER , REGER JOSEPH D. , SCHEUCHER MANFRED , LANDAU DAVID P.
Published: November 2004

This brief review discusses methods to locate and characterize first order phase transitions, paying particular attention to finite size effects. In the first part, the order parameter probability distribution and its fourth-order cumulant is discussed for thermally driven first-order transitions (the 3-state Potts model in d=3 dimensions is treated as an example). First-order transitions are characterized by a minimum of the cumulant, which gets very deep for large enough systems. In the second part, we discuss how to locate first order phase boundaries ending in a critical point in a large parameter space. As an example, the study of the unmixing transition of asymmetric polymer mixtures by a combination of histogram techniques and finite size scaling is described.

As a final problem, we discuss the shift of the gas-liquid condensation in thin-film geometry confined between two parallel plates due to boundary fields (“capillary condensation”). Being interested in temperatures far below bulk criticality (e. g. near the wetting transition), special thermodynamic integration techniques are the method of choice, rather than the use of finite sizes scaling to map out the (asymmetric) phase diagram.
SUSCEPTIBILITY SINGULARITIES AT FIRST-ORDER PHASE TRANSITIONS
Authors: ABRAHAM D.B. , UPTON P.J.
Published: November 2004

Problems associated with analyticity of thermodynamic functions close to first-order phase transitions are briefly reviewed. The bubble model for correlation functions is then applied to planar Ising-like models at subcritical temperatures (T<Tc) with a bulk magnetic field h. The fluctuation sum is used to calculate the susceptibility χ(h) from the bubble correlation function. We show that χ(h), calculated this way, must contain an essential singularity at h=0 i.e. at the first-order phase boundary. This has important implications to metastability, where we demonstrate that if the ensemble is restricted such that the magnetization stays positive when h goes negative, χ(h) has an infinite number of poles along the negative real axis with a limit-point at h=0. For an unrestricted ensemble, a Yang-Lee circle theorem is derived.
MULTICANONICAL SIMULATION OF THE TWO-DIMENSIONAL 7-STATE POTTS MODEL
Authors: JANKE WOLFHARD
Published: November 2004

Using multicanonical Monte Carlo simulations, we have calculated the interface free energy between the coexisting ordered and disordered phase at the temperature driven first-order phase transition of the two-dimensional 7-state Potts model. Our result 2f3= 0.0241±0.0010 is about an order of magnitude smaller than other estimates in the recent literature. We discuss the differences in analysis and give a possible explanation for the discrepancy. Finally, we briefly mention similar investigations at the deconfining phase transition of SU(3) lattice gauge theory.
PAIR INTERACTION LATTICE GAS ON GENERAL PURPOSE COMPUTERS: FORTRAN OR C?
Authors: WOLF-GLADROW DIETER , VOGELER ARMIN
Published: November 2004

We report on performance tests of pair interaction lattice gas automata in two and three dimensions coded in FORTRAN and C. The programs have been run on ALLIANT/FX-80, ALLIANT/FX-2800, CONVEX C2, CRAY-YMP, NEC/SX3, and SUN/IPC. The maximum update rates are 200 million site updates per second on the NEC/SX3 (FORTRAN), 117 (2D version) and 29 (3D version) on the CRAY-YMP (C). As a byproduct we give results for the performance of integer arithmetic and bit operations. Usually the C-programs were somewhat faster than the FORTRAN-programs except on the NEC/SX3 where the C-compiler was not able to vectorize the main loops.
COMPUTER ALGEBRA AND ITS APPLICATIONS IN PHYSICS
Authors: STEEB W.-H.
Published: November 2004

Computer algebra is a powerful tool in the study of a wide class of problems in mathematics, physics, and engineering. The primary domain of computer algebra is the solution of large scale formal problems. We give an introduction and survey on computer algebra. In particular we show with examples how problems in physics can be solved. We also show with an example how object-oriented programming can be used in such problems.
QUANTUM REACTIVE SCATTERING USING THE S-MATRIX KOHN VARIATIONAL METHOD
Authors: ZHANG JOHN Z.H.
Published: November 2004

This paper intends to give a short review on the recent progress and application of the S-matrix Kohn variational method to quantum reactive scattering in gas phase. The basic formalisms of the S-matrix Kohn method are reviewed and several numerical techniques that improve the efficiency of the Kohn method are described in the review. These include the body-fixed representation, quasi-adiabatic basis contraction method, and the use of distorted waves in numerical application. The efficacy of these numerical techniques are illustrated by numerical results obtained by using the latest version of the S-matrix Kohn variational method for three-dimensional F+H2 and F+D2 reactions.
INVESTIGATION OF INTERMITTENCY IN 28Si-NUCLEUS COLLISIONS AT 14.5A GeV
Authors: JAIN P.L. , SINGH G.
Published: November 2004

Scaled factorial moments are computed for the multiplicity distributions of the 28 Si -emulsion interactions at 14.5A GeV in one- and two-dimensional phase spaces. An intermittency power-law is observed for the central collisions. The observations are found to be different in higher dimensions and they are compared with the other heavy-ion projectiles.
DIRAC FIELD IN THE EIGHT-DIMENSIONAL KALUZA-KLEIN THEORY
Authors: MACIAS A. , DEHNEN H.
Published: November 2004

We consider the eight-dimensional Kaluza-Klein theory where the extra dimensions are a SU(2)×U(1) group manifold. A Dirac-field is coupled to the metric field. As a result we obtain that the four-dimensional theory is non-chiral and contains no-kind of Higgs mechanism to predict gauge bosons, quark and lepton masses and mixing angles, although it exhibit to possess all gauge bosons and fermionic isospin couplings for left-handed particles of a Weinberg-Salam theory in a curved space-time.
EXACTLY SOLUBLE MATRIX MODELS
Authors: VISWANATHAN R. RAJU
Published: November 2004

We study examples of one-dimensional matrix models whose potentials possess an energy spectrum that can be explicitly determined. This allows for an exact solution in the continuum limit. Specifically, step-like potentials and the Morse potential are considered. The step-like potentials show no scaling behavior and the Morse potential (which corresponds to a γ=−1 model) has the interesting feature that there are no quantum corrections to the scaling behavior in the continuum limit.
PERTURBATIVE FINITENESS OF 2D INDUCED QUANTUM GRAVITY
Authors: ODINTSOV S.D. , SHAPIRO I.L.
Published: November 2004

The divergences structure of the local 2D induced quantum gravity in the generally covariant gauge of the general type is considered. It is shown that for the particular choice of this gauge the effective action is perturbatively finite. This fact is in full agreement with the fact that the theory is exactly solvable.
ENHANCED LEPTON FLAVOR VIOLATION WITH MASSLESS NEUTRINOS: A STUDY OF MUON AND TAU DECAYS
Authors: GONZALEZ-GARCIA M.C. , VALLE J.W.F.
Published: November 2004

Lepton flavor violating rates can be experimentally measurable even if the observed neutrinos are strictly massless. We make a study of the attainable rates for anomalous leptonic muon and tau number violating decays such as μ→eγ, μ→3e, τ→μγ, τ→eγ, τ→μμ+ μ−, τ→ ee+e−, τ→eμ+μ−, etc. as well as semileptonic lepton flavor violating tau decays such as τ→μπ0, τ→eπ0, τ→eη, etc. All muonic violating decays can be as large as the present limits from LAMPF, TRIUMF and PSI. The corresponding tau violating processes can all be at the limit of sensitivity of the upcoming τ factories.
SEMI-FREE FIELD REPRESENTATION AND STRING FIELD THEORY IN 2D GRAVITY
Authors: AREF’EVA I. YA. , ZUBAREV A.P.
Published: November 2004

String field theory for 2D gravity coupled to a c=1 matter field is described. We use the free field representation and take into account the semi-bounded of the Liouville mode in the last step of calculations. We call such representation semi-free field representation. It is shown that the Witten string field theory gives a tachyon action which up to some, factor in the interaction term coincides with the Das-Jevicki-Polchinski action.

Starting from string field theory with semi-free field representation we calculate string amplitudes. These amplitudes instead of energy conservation δ-functions contain energy denominators which residues coincide with the Veneziano (Shapiro-Virasoro) amplitudes for open (closed) string and exhibit very interesting property: the s, t and u poles become the poles in respect to individual external momentum. These poles are related with higher levels excitations living only with fixed momentum.
GENERALIZED DEFORMED VIRASORO ALGEBRAS
Authors: DASKALOYANNIS C.
Published: November 2004

The deformed Virasoro algebra is a structure, generated by a generalized deformed oscillator algebra. The usual or the q-deformed centerless Virasoro algebras are special cases of this structure, and their properties can be reduced from the properties of the generalized deformed algebra. The construction of other deformed Virasoro algebras is given, using known deformation schemes other than the q-deformation.
PRE-EQUILIBRIUM PRODUCTION OF PHOTONS AND LEPTONS IN RELATIVISTIC HEAVY-ION COLLISIONS
Authors: CHAKRABARTY SOMENATH , RAHA SIBAJI , SINHA BIKASH
Published: November 2004

Within the framework of a model similar to Brownian motion in a thermal bath where gluons equilibrate at times earlier than the quarks, it is argued that simultaneous observation of inclusive photons and photon pairs provides a ‘clue’ to the collective distribution of glue in an extended space-time regime.
INFLATION AND COMPACTIFICATION DERIVED FROM DUALITY INVARIANT GAUGINO CONDENSATION
Authors: STEWART N.R.
Published: November 2004

Recently it has been demonstrated that the breaking of space-time supersymmetry in the context of string-induced effective actions may be realized in a duality invariant way using gaugino condensates. Although generically the ground state is a negative minimum, we present a toy model of a Hawking-Moss type inflation by invoking a one-loop Casimir effect and adjusting the cosmological constant to zero. This can only be justified a posteriori since we obtain inflation and compactification of the target space albeit fine-tuning is necessary.
DYNAMICAL GENERATION OF THE EFFECTIVE POTENTIAL IN SUPERSTRING THEORY
Authors: CLAVELLI L. , HARMS B. , LEBLANC Y.
Published: November 2004

We obtain the effective potential of the type-II superstring with broken supersymmetry due to twisted toroidal compactification of one of the string coordinates. Supersymmetry breaking of this type is shown to yield non-vanishing contact interactions among the massless modes at genus-1 order, thus dynamically providing the theory with a nontrivial effective potential. We argue that, if for a general compactification scheme the sum of this potential and tree level contributions has a minimum(zero total tadpole), this would provide us with a self-consistent criterion for selecting true string vacua.
AFFINE (TWO-LOOP) WZNW MODEL, REDUCTION AND SPONTANEOUS BREAKDOWN OF CONFORMAL SYMMETRY
Authors: ZHANG YAO-ZHONG
Published: November 2004

A large theory—the affine (two-loop) WZNW theory, which is universal in the sense that (at least classically) conformal and integrable models may be considered as its various reductions, has been proposed in our recent papers with Bonora and Martellini. In this letter we study a different Hamiltonian reduction (named as type III reduction in the text) of the affine (two-loop) WZNW model and discuss the integrability property of the reduced model. By a BRST analysis, we elaborate on a previously introduced idea regarding integrable systems as spontaneously conformal-symmetry-broken versions of CFTs.
QUANTUM RINGS AND RECURSION RELATIONS IN 2D QUANTUM GRAVITY
Authors: KACHRU SHAMIT
Published: November 2004

I study tachyon condensate perturbations to the action of the two-dimensional string theory corresponding to the c=1 matrix model. These are shown to deform the action of the ground ring on the tachyon modules, confirming a conjecture of Witten. The ground ring structure is used to derive recursion relations which relate (N+1) and N tachyon bulk scattering amplitudes. These recursion relations allow one to compute all bulk amplitudes.
A NOTE ON THE KP HIERARCHY
Authors: DEPIREUX DIDIER A.
Published: November 2004

Given the two boson representation of the conformal algebra Ŵ∞, the second Hamiltonian structure of the KP hierarchy, I construct a bi-Hamiltonian hierarchy for the two associated currents. The KP hierarchy appears as a composite of this new and simpler system. The bi-Hamiltonian structure of the new hierarchy gives naturally all the Hamiltonian structures of the KP system.
A COMMENT ON WITTEN’S TOPOLOGICAL LAGRANGIAN
Authors: NASH CHARLES
Published: November 2004

The occurrence of distinct differentiable structures in four dimensions is examined within the framework of Witten’s topological Lagrangian.
ARE 100 GeV ELECTRON-ELECTRON COLLISIONS INTERESTING?
Authors: FRAMPTON PAUL H.
Published: November 2004

It is pointed out that e−e−→µ−µ− at center of mass energy=100 GeV can be sensitive to dileptonic gauge bosons in an unexplored mass region; such states are predicted in a wide class of theories.
$K_{l_4}$ DECAY ANALYSIS IN A PARAMETER-FREE RELATIVISTIC MODEL
Authors: RAMANATHAN R.
Published: November 2004

The dimensionless form factors fs(0), g(0), h(0) and λ which account for almost all the microscopic details of the [Formula: see text] decay are computed in an integrated QCD oriented Bethe-Salpeter framework, where all the free parameters involved in the formalism are fixed by the best fit with the Hadron mass spectroscopy, so that for the present evaluation we have a parameter-free model. The values of the form factors so obtained are in good agreement with the experimental values and the agreement is comparable with the recent similar calculations using large-Nc limits in chiral QCD theory.
TESTS OF CP AND CPT WITH POLARIZED POSITRONIUM
Authors: SKALSEY MARK
Published: November 2004

Two experiments, using polarization techniques with triplet positronium (Ps), have searched for violations of initially the CPT and, most recently, the CP symmetries. Angular correlations between the Ps spin (S) and the momenta of the decay λ-rays (|k1| > |k2| > |k3|) were measured: [Formula: see text] The coefficients, Cn and C CP , are expected to be zero if the respective symmetries areconserved. No symmetry violations were observed in either experiment at the 2.3% and1.5% level of uncertainty, respectively, in the angular correlation coefficients.
UNITARY MATRIX MODELS AND 2D QUANTUM GRAVITY
Authors: DALLEY S. , JOHNSON C. V. , MORRIS T. R. , WÄTTERSTAM A.
Published: November 2004

The KdV and modified KdV integrable hierarchies are shown to be different descriptions of the same 2D gravitational system — open-closed string theory. Non-perturbative solutions of the multicritical unitary matrix models map to non-singular solutions of the 'renormalization group' equation for the string susceptibility, [Formula: see text]. We also demonstrate that the large-N solutions of unitary matrix integrals in external fields, studied by Gross and Newman, equal the non-singular pure closed-string solutions of [Formula: see text].
FLAVOR SU(4) BARYON AND MESON MASSES IN DIQUARK-QUARK MODEL USING THE PAULI-GÜRSEY SYMMETRY
Authors: SUZUKI K. , TOKI H.
Published: November 2004

We study the color-current Nambu and Jona-Lasinio model for mesons and diquarks and find that the masses of diquarks are the same as meson masses of the same spin and the opposite parity with the same flavor content due to the Pauli-Gürsey symmetry. By taking the weak coupling diquark-quark model for baryons, we calculate the baryon masses with the use of the known meson masses through the Pauli-Gürsey symmetry. The agreement with the existing data is extremely good. We predict several SU(4) baryon masses with charms to be checked experimentally.
TARGET SPACE INTERPRETATION OF NEW MODULI IN 2D STRING THEORY
Authors: MAHAPATRA SWAPNA , MUKHERJI SUDIPTA , SENGUPTA ANIRVAN M.
Published: November 2004

We analyze the new states that have recently been discovered in 2D string theory by E. Witten and B. Zwiebach. Since the Liouville direction is uncompactified, we show that the deformations by the new ghost number two states generate equivalent classical solutions of the string fields. We argue that the new ghost number one states are responsible for generating transformations which relate such equivalent solutions. We also discuss the possible interpretation of higher ghost number states of these.
SUPERRADIANCE FROM A CHARGED DILATON BLACK HOLE
Authors: SHIRAISHI KIYOSHI
Published: November 2004

We study the behavior of the wave function of charged Klein-Gordon field around a charge dilaton black hole. The rate of spontaneous charge loss is estimated for large black hole case.
THE OPERATOR PRODUCT EXPANSION OF THE QCD PROPAGATORS
Authors: LAVELLE MARTIN , OLESZCZUK MICHAEL
Published: November 2004

We bring together for the first time the coefficients in covariant gauges of all the condensates of dimension four or less in the operator product expansion (OPE) of the quark, gluon and ghost propagators. It is stressed that contrary to general belief the condensates do not enter the OPE of the propagators in gauge-invariant combinations like [Formula: see text] and 〈G2〉. The results are presented in arbitrary dimension to lowest order in the light quark masses for the SU (Nc) internal symmetry group. All terms which, through the equations of motion, may be viewed as being effectively of order αs are included. The importance of the equations of motion if one is to fulfill the Slavnov-Taylor identities is demonstrated. We briefly consider the equivalent, but less complete, calculations in other gauges and give an overview of the status of the OPE of the QCD vertices. Finally we discuss what these non-perturbative structures tell us about the correct solutions of QCD and point out their significance for the Fourier acceleration technique as applied to lattice QCD.
NON-ABELIAN CHIRAL SCALARS FROM THE MODIFIED WESS-ZUMINO-WITTEN ACTION
Authors: KIM WON-TAE , SHIN HYEONJOON , PARK YOUNG-JAI
Published: November 2004

We study a system of non-Abelian chiral bosons which is described by the modified Wess-Zumino-Witten (W2W) action. We show that a single chiral boson and left-right chiral bosons appear according to a parameter in the action.
STATISTICS OF LINKED STRINGS
Authors: ANEZIRIS CHARILAOS
Published: November 2004

We discuss the possibilities for statistics of identical strings when they are linked. We show that while there are possibilities for novel statistics and for a violation of the spin-statistics relation, the results we get are different from the ones for unlinked strings.
THE BAXTERIZATION OF THE ZAMOLODCHIKOV MODEL
Authors: EMIL VINTELER
Published: November 2004

We use the method of M. P. Bellon, J.-M. Maillard, C. Viallet to construct continuous families of solutions from an isolated one, known as the baxterization, for the Zamolodchikov model. The algebraic varieties which were obtained may be useful in order to search for the invariants for models which generalize the Zamolodchikov model.
SUPERSYMMETRY IN THE TWO-ANYON PROBLEM
Authors: CHITRA R. , KUMAR C. NAGARAJA , SEN DIPTIMAN
Published: November 2004

We show that the problem of two anyons interacting through a simple harmonic potential or a Coulomb potential is supersymmetric. The supersymmetry operators map a theory described by statistics parameter θ to one described by π+θ. Thus fermions and bosons go into each other, while semions are supersymmetric by themselves. The simple harmonic problem has a Sp(4) symmetry for any value of θ which explains the energy degeneracies.
THE MARINARI-PARISI MODEL AND COLLECTIVE FIELD THEORY
Authors: COHN J. D. , DYKSTRA H.
Published: November 2004

We derive the supersymmetric collective field theory for the Marinari-Parisi model. For a specific choice of the superpotential, to leading order we find a one-parameter family of ground states which can be connected via instantons. At this level of analysis the instanton size implied by the underlying matrix model does not appear.
A NEW ANSATZ FOR QUARK AND LEPTON MASS MATRICES
Authors: GIUDICE GIAN F.
Published: November 2004

A new ansatz for quark and lepton mass matrices is proposed in the context of supersymmetric grand unified theories. The 13 parameters describing fermion masses and mixings are determined in terms of only 6 free parameters, allowing 7 testable predictions. The values of Vus, Vcb, Vub, mu, md, ms and mb are then predicted as a function of the 3 charged lepton masses, mc, mt and tan β, the ratio of Higgs vacuum expectation values. In particular the Cabibbo angle and ms/md are determined in terms of only lepton masses. All predictions are in very good agreement with experiments.
A COSMOLOGY WITH CONFORMALLY COUPLED SCALAR FIELD
Authors: NG KIN-WANG
Published: November 2004

A theory of gravitation with a conformally coupled scalar field is considered in which the gravitational “constant” is associated with the vacuum expectation value of the scalar field. It is found that the universe will remain dominated by classical radiation unless the conformal symmetry is broken. The equations of motion thus derived bear a de Sitter phase solution, which could have an exponential growth of the cosmic scale factor with no vacuum energy. We discuss the cosmological implications of this kind of “inflation”. We also find that in the present theory the smallness of the vacuum energy for most time of the universe is due to the constancy of the gravitational “constant”.
CONDENSATION ENERGY OF THE NAMBU-JONA-LASINIO VACUUM AND THE MIT BAG CONSTANT
Authors: LI SHUXI , BHALERAO R.S. , BHADURI R.K.
Published: November 2004

The energy densities of the vacuum in the Wigner and the Goldstone modes of the Nambu-Jona-Lasinio Hamiltonian are calculated. The difference of these two quantities is analogous to the condensation energy of a BCS superconductor, and is used here to estimate the temperature dependence of the MIT bag constant. The formalism of da Providencia et al. is generalized to finite temperatures, yielding the same gap equation as the finite-temperature field theory. The thermodynamics of the vacuum in the two phases is studied.
ALGORITHM DEPENDENCE OF PARTON SHOWERS IN DEEP INELASTIC SCATTERING
Authors: MUNEHISA TOMO , TANAKA HIDEKAZU
Published: November 2004

Parton showers for deep inelastic electron-proton scattering are studied. Forward and backward evolution algorithms are constructed using the same definitions for splitting and evolution variables. We discuss features of two algorithms and examine algorithm dependence of final parton distributions.
(2, 2) VACUA OF THE HETEROTIC SUPERSTRING COMPACTIFIED ON SU(2)3 GROUPFOLDS
Authors: CASTELLANI LEONARDO , FRE’ PIETRO , GLIOZZI FERDINANDO , MONTEIRO MARCO R.
Published: November 2004

In this paper we classify the (2, 2) superstring vacua corresponding to non-linear σ-models on SU (2)3 groupfolds fermionized by 18 + 18 Majorana fermions. For the subclass of the completely bosonizable vacua, the generation number ½X is a multiple of 12 and the number of tangent-bundle deformations End(T) is a multiple of 4. The dimensions of the moduli spaces h1,1, h2, 1 are small odd numbers in the range 1 ÷ ~50. Very few of these vacua have the same Dolbeault cohomology as those described by minimal model tensor products, CICY, or Calabi-Yau threefolds in weighted P4. The vacua we classify are characterized by a rank 8 enhancement group and some of them can be viewed as N=2 truncations. We also discuss examples of vacua that are only partially bosonizable, showing that the class of vacua obtained by free fermion constructions is not fully contained in the class of vacua obtained by lattice constructions.
CP ASYMMETRIES IN B0DECAYS BEYOND THE STANDARD MODEL
Authors: DIB CLAUDIO O. , LONDON DAVID , NIR YOSEF
Published: November 2004

Of the many ingredients of the Standard Model that are relevant to the analysis of CP asymmetries in B0 decays, some are likely to hold even beyond the Standard Model while others are sensitive to new physics. Consequently, certain predictions are maintained while others may show dramatic deviations from the Standard Model. Many classes of models may show clear signatures when the asymmetries are measured: four quark generations, Z-mediated flavor-changing neutral currents, supersymmetry and “real superweak” models. On the other hand, models of left-right symmetry and multi-Higgs sectors with natural flavor conservation are unlikely to modify the Standard Model predictions.
STRING EQUATIONS OF MOTION FROM VANISHING CURVATURE
Authors: BOWICK MARK J. , YANG KONG-QING
Published: November 2004

The equations of motion for the massless modes of the closed bosonic string are obtained in the adiabatic approximation from the requirement of the vanishing of the curvature of appropriate vector bundles over the space of complex structures Diff S1/S1. This vanishing is required for physical states to be independent of string parametrization.
EXACT S-MATRICES FOR ϕ1,2-PERTURBATED MINIMAL MODELS OF CONFORMAL FIELD THEORY
Authors: SMIRNOV F.A.
Published: November 2004

The S-matrices for ϕ1,2-perturbated minimal models are shown to be connected with RSOS projections of the [Formula: see text]R-matrix. The agreement with the known particular cases (E6, E7, E8, D4) is established.
QUARK DISTRIBUTION IN A POLARIZED NUCLEON IN QCD
Authors: BELYAEV V.M. , IOFFE B.L.
Published: November 2004

The method proposed in the previous papers by the authors1,2 is applied to calculation of quark distributions in a polarized nucleon. It is based on the operator expansion and is a generalization of the QCD sum rule approach applying to the given problem.
MASS FORMULAE IN TODA FIELD THEORIES
Authors: KOCA MEHMET , MUSSARDO GIUSEPPE
Published: November 2004

The characteristic equations which give the mass spectrum of the affine Toda field theories are analyzed. In order to determine the decoupling point of the finite renormalization due to the tadpoles we introduce the so-called mass formulae. We derive the recursive equations the mass formulae satisfy and study their properties for all Lie algebras. For the ADE series the mass formulae turn out to be sequences of integers.
ELECTROWEAK SYMMETRY BREAKING AND DYNAMICS OF TIGHT BOUND STATES
Authors: MIRANSKY VLADIMIR A.
Published: November 2004

The problem of dynamic electroweak symmetry breaking (DEWSB) is reviewed. The emphasis is on the consideration of the dynamics of spinless tight bound states which can be an essential ingredient of the DEWSB scenario.
THE GAUGE-INVARIANT THEORY OF HIGHER SPIN FIELDS IN CURVED SPACE
Authors: AVRAMIDI I.G.
Published: November 2004

It is shown that the gauge-invariant description of higher spin fields requires a nonlocal generalisation of the theory. Nonlocal gauge-invariant action functionals for spin 3/2 field and tensor spin 2 field in curved space are constructed.
A BOSONIC MODEL FOR PARTICLES WITH ARBITRARY SPIN
Authors: HASIEWICZ ZBIGNIEW , SIEMION PRZEMYSŁAW , DEFEVER FILIP
Published: November 2004

We formulate a simple classical model without Grassmann variables. Quantization of this model gives a unified quantum-mechanical description for massive and massless particles of arbitrary spin and helicity. In the phase space of the classical model a “bosonic” version of the super-Poincaré algebra is realized. At the quantum level it generates the spectrum of the model.
COVARIANT QUANTIZATION OF BROKEN TWISTED N=2 SUPERPARTICLE
Authors: HUQ M.
Published: November 2004

We have considered a superparticle action consisting of an infinite tower of Siegel superparticle actions plus a term breaking all the twisted N=2 supersymmetries down to the required N=1 supersymmetry. With appropriate gauge choice we arrive at a quadratic gauge-fixed action, which naturally possesses an infinite sequence of twisted N=2 supersymmetries, but the BRST operator picks out the correct physical states for the Brink-Casalbuoni-Schwarz superparticle.
ON THE DERIVATION OF THE WHEELER-DEWITT EQUATION IN THE HETEROTIC SUPERSTRING THEORY
Authors: POLLOCK M.D.
Published: November 2004

It has been shown by Pollock that the Wheeler-DeWitt equation for the wave function of the Universe Ψ cannot be derived for the D-dimensional, heterotic superstring theory, when higher-derivative terms [Formula: see text] are included in the effective Lagrangian [Formula: see text], because they occur as the Euler-number density [Formula: see text]. This means that [Formula: see text] cannot be written in the standard Hamiltonian form, and hence that macroscopic quantum mechanics does not exist at this level of approximation. It was further conjectured that the solution to this difficulty is to take into account the effect of the terms [Formula: see text], an expression for which has been obtained by Gross and Witten, and by Freeman et al. Here, this conjecture is proved, but it is pointed out that the theory must first be reduced to a lower dimensionality [Formula: see text]. When this is done, the reduced term R2 is no longer proportional to [Formula: see text], because of additional contributions arising from the dimensional reduction of [Formula: see text]. The Wheeler-DeWitt equation can now be derived in the form of a Schrödinger equation, in particular when [Formula: see text] (and [Formula: see text] is a total divergence which can be discarded), and quantum mechanics can be set up in the usual way. In the light of these results, it is argued that the non-locality of quantum mechanics is related to the cosmological horizon problem.
QUANTUM FIELDS VERSUS STRINGS AT FINITE TEMPERATURE
Authors: OSORIO M.A.R.
Published: November 2004

We study some aspects of the relationship between the one-loop free energy of closed superstrings computed as a sum over the free energies of the quantum fields present in the string (the analog model) and the modular invariant expression of the same quantity. In particular, by getting a generalized duality relation for the integrand of the modular invariant expression for the free energy of closed superstrings and using a regularization procedure, we connect the contribution to the vacuum energy from the bosonic degrees of freedom in the analog model (one half of the total number) with the coefficient governing the high temperature behavior of the free energy. We also study the physical meaning of this regularization and the role played by the left-right constraint defining the physical fields in the light-cone gauge.
GAUGE THEORY FORMULATION OF THE c=1 MATRIX MODEL: SYMMETRIES AND DISCRETE STATES
Authors: DAS SUMIT R. , DHAR AVINASH , MANDAL GAUTAM , WADIA SPENTA R.
Published: November 2004

We present a nonrelativistic fermionic field theory in two dimensions coupled to external gauge fields. The singlet sector of the c=1 matrix model corresponds to a specific external gauge field. The gauge theory is one-dimensional (time) and the space coordinate is treated as a group index. The generators of the gauge algebra are polynomials in the single particle momentum and position operators and they form the group [Formula: see text]. There are corresponding Ward identities and residual gauge transformations that leave the external gauge fields invariant. We discuss the realization of the residual symmetries in the Minkowski time theory and conclude that the symmetries generated by the polynomial basis are not realized. We motivate and present an analytic continuation of the model which realizes the group of residual symmetries. We consider the classical limit of this theory and make the correspondence with the discrete states of the c=1 (Euclidean time) Liouville theory. We explain the appearance of the SL(2) structure in [Formula: see text]. We also present all the Euclidean classical solutions and the classical action in the classical phase space. A possible relation of this theory to the N=2 string theory and also self-dual Einstein gravity in four dimensions is pointed out.
VACUUM POLARIZATION TENSOR IN THREE-DIMENSIONAL QUANTUM ELECTRODYNAMICS
Authors: PIMENTEL B.M. , SUZUKI A.T. , TOMAZELLI J.L.
Published: November 2004

We evaluate the one-loop vacuum polarization tensor for three-dimensional quantum electrodynamics (QED), using an analytic regularization technique, implemented in a gauge-invariant way. We show thus that a gauge boson mass is generated at this level of radiative correction to the photon propagator. We also point out in our conclusions that the generalization for the non Abelian case is straightforward.
GAUGE INVARIANCE AND CONSTRAINTS: OPEN GAUGE ALGEBRAS
Authors: NIROV KH. S. , PYATOV P.N. , RAZUMOV A.V.
Published: November 2004

For a wide class of gauge-invariant systems with open gauge algebras the Hamiltonian description is constructed and the Poisson brackets of the constraints are calculated. It is shown that in the case under consideration there arise only first class constraints.
EFFECTIVE ACTION AND THE ATOMIC ENERGY LEVELS
Authors: KOMACHIYA M. , FUKUDA R.
Published: November 2004

Applying the recently developed method of the on-shell expansion of the effective action, a compact equation is derived in the framework of the quantum electrodynamics which determines the energy levels of the hydrogen-, helium- and lithium-like atoms. Since they are derived systematically, our method provides a transparent formal derivation of the equations which includes the full order corrections.
SIMPSON’S 17 keV NEUTRINO IN MINIMALLY EXTENDED SU(2)L×U(1) ELECTROWEAK MODELS
Authors: TSAI S.Y.
Published: November 2004

It is shown that the standard SU(2) L× U(1) electroweak gauge model extended so as to incorporate a single right-handed neutrino singlet and a second Higgs doublet, supplemented with the singlet majoron hypothesis, can accommodate Simpson’s 17 keV neutrino in a rather unique way. A number of interesting phenomenological consequences follow from such a scheme, which are discussed.
ON THE VANISHING COUPLINGS IN $\hat{A}\hat{D}\hat{E}$ AFFINE TODA FIELD THEORIES
Authors: SAITOH YOSHIHIRO , SHIMADA TOKUZO
Published: November 2004

We show that certain vanishing couplings in the [Formula: see text] affine Toda field theories remain vanishing even after higher-order corrections are included. This is a requisite property for the Lagrangian formulation of the theory. We develop a new perturbative formulation and treat affine Toda field theories as a massless theory with exponential interaction terms. We show that the nonrenormalization comes from the Dynkin automorphism of the Lie algebra associated with these theories. A charge balance condition plays an important role in our scheme. The all-order nonrenormalization of vanishing couplings in [Formula: see text] affine Toda field theory is also proved in a standard massive scheme.
THE CHERN-SIMONS SOURCE AS A CONFORMAL FAMILY AND ITS VERTEX OPERATORS
Authors: BALACHANDRAN A.P. , BIMONTE G. , GUPTA K.S. , STERN A.
Published: November 2004

In a previous work, a straighforward canonical approach to the source-free quantum Chern—Simons dynamics was developed. It makes use of neither gauge conditions nor functional integrals and needs only ideas known from QCD and quantum gravity. It gives Witten’s conformal edge states in a simple way when the spatial slice is a disc. Here we extend the formalism by including sources as well. The quantum states of a source with a fixed spatial location are shown to be those of a conformal family, a result also discovered first by Witten. The internal states of a source are not thus associated with just a single ray of a Hilbert space. Vertex operators for both abelian and nonabelian sources are constructed. The regularized abelian Wilson line is proved to be a vertex operator. We also argue in favor of a similar nonabelian result. The spin-statistics theorem is established for Chern-Simons dynamics even though the sources are not described by relativistic quantum fields. The proof employs geometrical methods which we find are strikingly transparent and pleasing. It is based on the research of European physicists about “fields localized on cones.”
LOOP CALCULATIONS IN TWO-DIMENSIONAL NONLOCAL FIELD THEORIES
Authors: GRISARU M.T. , NIEUWENHUIZEN P. VAN
Published: November 2004

We perform one-loop calculations in chiral induced W3 gravity in momentum space. Unlike a previous one-loop calculation in x space, which reduced the problem to one in local field theory, we work directly with the nonlocal action. We use Polyakov’s exponential regularization, and obtain agreement with the x-space calculation. We discuss the extension of our methods to higher-loop calculations in more-general chiral nonlocal field theories.
N=2 COSET COMPACTIFICATIONS WITH NONDIAGONAL INVARIANTS
Authors: ALDAZABAL G. , ALLEKOTTE I. , FONT A. , NÚÑEZ C.
Published: November 2004

We consider four-dimensional string models obtained by tensoring N=2 coset theories with nondiagonal modular invariants. We present results from a systematic analysis including moddings by discrete symmetries.
PERTURBATIVE RECONFIRMATION OF THE EXACT COVARIANT SOLUTION TO THE TWO-DIMENSIONAL QUANTUM GRAVITY
Authors: ABE MITSUO , NAKANISHI NOBORU
Published: November 2004

The validity of the exact solution to the covariant operator formalism of two-dimensional quantum gravity is reconfirmed by means of the conventional perturbation theory. Only a finite number of Feynman graphs are encountered, yet, the perturbative approach is much more complicated than the exact method. A unitarized, covariantized Polyakov theory, which has an infinite number of Feynman graphs, is obtained from the above result by a simple field redefinition.
UNIVERSALITY AND NONPERTURBATIVE DEFINITIONS OF 2D QUANTUM GRAVITY FROM MATRIX MODELS
Authors: MIRAMONTES J. LUIS , SÁNCHEZ GUILLÉN JOAQUÍN
Published: November 2004

The universality of the nonperturbative definition of Hermitian one-matrix models following the quantum, stochastic, or d=1-like stabilization is discussed in comparison with other procedures. We also present another alternative definition, which illustrates the need of new physical input for d=0 matrix models to make contact with 2D quantum gravity at the nonperturbative level.
BOSONIZATION OF 2D CONFORMAL MINIMAL-LIKE FIELD THEORIES
Authors: LASHKEVICH M. YU.
Published: November 2004

Some primary fields of Virasoro algebra in bosonic representation of Kastor-Martinec-Qiu minimal-like theories are constructed and these theories are compared with coset constructions SU (2)k× SU (2)l/ SU (2)k+l. Some properties of more complex cosets are investigated.