December 1995 arXiv papers — page 3

Pinaki Majumdar, H. R. Krishnamurthy

We compute the (zero frequency) Hall coefficient $R_H$, and the high frequency Hall constant $R_H^*$ for the strong coupling Hubbard model away from half-filling, in the $d=\infty$/ local approximation, using the new iterated perturbation scheme proposed by Kajueter and Kotliar. We find quantitative agreement of our $R_H^*$ with the QMC results obtained in t

Victor Matveev, Robert Shrock

We prove that for the Ising model on a lattice of dimensionality $d \ge 2$, the zeros of the partition function $Z$ in the complex $μ$ plane (where $μ=e^{-2βH}$) lie on the unit circle $|μ|=1$ for a wider range of $K_{n n'}=βJ_{nn'}$ than the range $K_{n n'} \ge 0$ assumed in the premise of the Yang-Lee circle theorem. This range includes complex

Dale Gerdemann

This paper presents an approach to Prolog-style term encoding of typed feature structures. The type feature structures to be encoded are constrained by appropriateness conditions as in Carpenter's ALE system. But unlike ALE, we impose a further independently motivated closed-world assumption. This assumption allows us to apply term encoding in cases that

Michael Turner, Martin White

The inflationary potential and its derivatives determine the spectrum of scalar and tensor metric perturbations that arise from quantum fluctuations during inflation. The CBR anisotropy offers a promising means of determining the spectra of metric perturbations and thereby a means of constraining the inflationary potential. The relation between the metric pe

D. Schaerer

We present the EUV fluxes derived from the recent "combined stellar structure and atmosphere models" (CoStar models). The atmosphere models in particular account for the stellar wind and include non-LTE effects and line blanketing. We provide an extensive set of calculations from tracks between 20 and 120 Msun at Z=0.02 (solar metallicity) and Z=0.00

A. A. Brukhanov, D. P. Skulachev, I. A. Strukov, T. V. Konkina

We discuss the problem of CMB spectrum corruption during Galactic emission removing. A new technique of spatial--frequency data reduction is proposed. The technique gives us a possibility to avoid a spatial harmonics nonorthogonality. The proposed technique is applied to the two-year COBE DMR sky maps. We exclude the harmonics with l=7, 9,13, 23 and 25 as ha

S. Campana, M. Colpi, S. Mereghetti, L. Stella

Timing analisys of PSR 1259-63 during its recent periastron passage suggested that the pulsar was spinning-down due to the propeller mechanism (Manchester et al. 1995). This requires that the radio pulsar mechanism is temporarily quenched. On the basis of the Be equatorial disk model derived from the dispersion and rotation measures analysis (Melatos et al.

Karl Mannheim

A review on some recent developments in gamma ray astrophysics with particular emphasis on the role of relativistic bulk motion in nonthermal gamma ray sources, radiation processes in AGN jets, high-energy neutrino astronomy and the use of gamma rays in the energy range 10 GeV - 50 TeV as a probe of the diffuse IR-UV radiation field at cosmic distances.

Bharat Ratra, Anthony J. Banday, Krzysztof M. Gorski, Naoshi Sugiyama

We compute the CMB anisotropy in an open inflation CDM model which is normalized to the two-year DMR sky map. Presently available CMB data is consistent with $Ω_0 \sim 0.3 - 0.4$, but does not strongly disfavour either $Ω_0 \sim 0.1$ or $Ω_0 \sim 1$. Accumulating CMB data should strengthen the observational discriminative power, however, a better understandi

C. Charbonnel

Recent observations of 3He/H in different environments tend to prove that 3He is not produced in low mass stars, contrary to the standard predictions of stellar evolution theory. We show how a simple consistent mechanism, namely rotation-induced mixing, can lead to the destruction of 3He in low mass stars and simultaneously account for the low 12C/13C ratios

Takeo Moroi

The muon anomalous magnetic dipole moment (MDM) is calculated in the framework of the minimal supersymmetric standard model (MSSM). In this paper, we discuss how the muon MDM depends on the parameters in MSSM in detail. We show that the contribution of the superparticle-loop becomes significant especially when $\tanβ$ is large. Numerically, it becomes $O(10^

C. M. Hull

The dynamics of superstring, supergravity and M theories and their compactifications are probed by studying the various perturbation theories that emerge in the strong and weak coupling limits for various directions in coupling constant space. The results support the picture of an underlying non-perturbative theory that, when expanded perturbatively in diffe

Ramzi Khuri, Tomas Ortin

We present a dyonic embedding of the extreme Reissner-Nordström black hole in $N=4$ and $N=8$ supergravity that breaks all supersymmetries.

Ramzi Khuri, Tomas Ortin

We study the embedding of extreme (multi-) dilaton black hole solutions for the values of the parameter $a=\sqrt{3},1,1/\sqrt{3},0$ in $N=4$ and $N=8$ four-dimensional supergravity. For each black hole solution we find different embeddings in $N=4$ supergravity which have different numbers of unbroken supersymmetries. When embedded in $N=8$ supergravity, all

Dan Radu Grigore

We continue the study of symmetries in the Lagrangian formalism of arbitrary order with the help of the so-called Anderson-Duchamp-Krupka equations. For the case of second-order equations and arbitrary vector fields we are able to establish a polynomial structure in the second-order derivatives. This structure is based on the some linear combinations of Olve

Jan Bartelski, Stanisław Tatur

A fit to proton, neutron and deuteron spin asymmetries is presented and polarized parton distributions in nucleon are given. These densities have their roots in the MRS fit for unpolarized case. The integrals of polarized distributions are compared with the experimental figures. The role of polarized gluons is also discussed.

Chan Hong-Mo, J. Faridani, Tsou Sheung Tsun

It is shown that classical nonsupersymmetric Yang-Mills theory in 4 dimensions is symmetric under a generalized dual transform which reduces to the usual dual *-operation for electromagnetism. The parallel phase transport $\tilde{A}_μ(x)$ constructed earlier for monopoles is seen to function also as a potential in giving full description of the gauge field,

Hassen Jallouli, Hagop Sazdjian

The four-point Green's function of static QED, where a fermion and an antifermion are located at fixed space positions, is calculated in covariant gauges. The bound state spectrum does not display any abnormal state corresponding to excitations of the relative time. The equation that was established by Mugibayashi in this model and which has abnormal sol

Yoshihiko Nonomura, Hidetoshi Nishimori

The Hopfield model in a transverse field is investigated in order to clarify how quantum fluctuations affect the macroscopic behavior of neural networks. Using the Trotter decomposition and the replica method, we find that the $α$ (the ratio of the number of stored patterns to the system size)-$Δ$ (the strength of the transverse field) phase diagram of this

J. Richard Bond

The CMB is a remarkably distortionless blackbody, and this strongly constrains the amount of energy that can have been injected at high redshift, thereby limiting the role that hydrodynamical amplification can have played in cosmic structure formation. The current data on primary anisotropies (those calculated using linear response theory) provide very stron

S. Meljanac, M. Milekovic, A. Perica

We construct and discuss the Fock-space representation for a deformed oscillator with "peculiar" statistics. We show that corresponding algebra represents deformed supersymmetric oscillator.

A. Shariati, A. Aghamohammadi, M. Khorrami

We introduce a universal R matrix for the Jordanian deformation of $\U{ \sl(2)}$. Using $\Uh{\so(4)}=\Uh{\sl(2)} \oplus {\rm U}_{-h}(\sl(2))$, we obtain the universal R matrix for $\Uh{\so(4)}$. Applying the graded contractions on the universal R matrix of $\Uh{\so(4)}$, we show that there exist three distinct R matrices for all of the contracted algebras. I

Kotov Alexey

We check The Vaisman condition of geometric quantization for R-matrix type Poisson pencil on a coadjoint orbit of a compact Lie group. It is shown that this condition isn't satisfied.

R. J. Furnstahl, Hua-Bin Tang

The construction of a general effective lagrangian consistent with the symmetries of QCD and intended for applications to finite-density systems is discussed. The low-energy structure of the composite nucleon is described within the theory from vector-meson dominance. Results are given for finite nuclei and nuclear matter at one-loop order. All of the coupli

O. I. Kartavtsev

A few per cent fraction of antiprotons stopped in helium survives for an enormous time (up to tens of microseconds) in comparison with the usual lifetime ($10^{-12}s$) of these particles in matter. The explanation is that antiprotons are captured in the metastable antiprotonic helium atoms $^{3,4}\! H\! e\bar pe$ carrying an extremely large total angular mom

S. Goedecker, M. Teter, J. Hutter

We present pseudo-potential coefficients for the first two rows of the periodic table. The pseudo potential is of a novel analytic form, that gives optimal efficiency in numerical calculations using plane waves as basis set. At most 7 coefficients are necessary to specify its analytic form. It is separable and has optimal decay properties in both real and Fo

Mathijs S. Dijkhuizen

We present a general survey of some recent developments regarding the construction of compact quantum symmetric spaces and the analysis of their zonal spherical functions in terms of $q$-orthogonal polynomials. In particular, we define a one-parameter family of two-sided coideals in $\Uq(\gog\gol(n,\CC))$ and express the zonal spherical functions on the corr

Avinash Khare

A class of exact solutions are obtained for the problem of N-anyons interacting via the N-body potential $V (\vec x_1,\vec x_2,...,\vec x_N)$ = $-{e^2\over\sqrt{{1\over N}\sum_{i<j} (\vec x_i-\vec x_j)^2}}$ Unlike the oscillator case the resulting spectrum is not linear in the anyon parameter $α(0\leq α\leq 1)$. However, a la oscillator case, cross-over betw

Alexander Berkovich, Barry M. McCoy, Anne Schilling

We demonstrate that the Bailey pair formulation of Rogers-Ramanujan identities unifies the calculations of the characters of $N=1$ and $N=2$ supersymmetric conformal field theories with the counterpart theory with no supersymmetry. We illustrate this construction for the $M(3,4)$ (Ising) model where the Bailey pairs have been given by Slater. We then present

S. Ferrara, L. Girardello, M. Porrati

We analyze the relation between rigid and local supersymmetric N=2 field theories, when half of the supersymmetries are spontaneously broken. In particular, we show that the recently found partial supersymmety breaking induced by electric and magnetic Fayet-Iliopoulos terms in rigid theories can be obtained by a suitable flat limit of previously constructed

T. Heinzl, C. Stern, E. Werner, B. Zellermann

We discuss the vacuum structure of $ϕ^4$-theory in 1+1 dimensions quantised on the light-front $x^+ =0$. To this end, one has to solve a non-linear, operator-valued constraint equation. It expresses that mode of the field operator having longitudinal light-front momentum equal to zero, as a function of all the other modes in the theory. We analyse whether th

J. L. Petersen, J. Rasmussen, M. Yu

Talk presented by J.L. Petersen at the 29th Symposium Ahrenshop, Buckow August 29-September 2, 1995. A presentation is given of the free field realization relevant to SL(2) WZW theories with a Hilbert space based on admissible representations. It is known that this implies the presence of two screening charges, one involving a fractional power of a free fiel

S. Penati, A. Refolli, D. Zanon

In this paper we present a detailed study of the quantum conservation laws for Toda field theories defined on the half plane in the presence of a boundary perturbation. We show that total derivative terms added to the currents, while irrelevant at the classical level, become important at the quantum level and in general modify significantly the quantum bound

Yoshitaka Okumura

The standard model is reconstructed by new method to incorporate strong interaction into our previous scheme based on the non-commutative geometry. The generation mixing is also taken into account. Our characteristic point is to take the fermion field so as to contain quarks and leptons all together which is almost equal to that of SO(10) grand unified theor

I. Ya. Arefeva, K. S. Viswanathan, I. V. Volovich

In a series of papers Amati, Ciafaloni and Veneziano and &#39;t Hooft conjectured that black holes occur in the collision of two light particles at planckian energies. In this talk based on \cite {AVV} we discuss a possible scenario for such a process by using the Chandrasekhar-Ferrari-Xanthopoulos duality between the Kerr black hole solution and colliding p

I. Ya. Arefeva

In this talk the Schwarz hypothesis that the duality symmetries should be pieces of the hidden gauge symmetry in a string theory is discussed. Using auxiliary linear system special dual transformations for $N=4$ SYM generalizing the Schwarz dual transformations for a principal chiral model are constructed. These transformations are related with a continuous

T. W. Allen, C. J. Burden

The $e^-$-$e^+$ bound state spectrum of QED3 is investigated in the quenched ladder approximation to the homogeneous Bethe-Salpeter equation with fermion propagators from a rainbow approximation Schwinger-Dyson equation. A detailed analysis of the analytic structure of the fermion propagator is performed so as to test the appropriateness of the methods emplo

Michael G. Sotiropoulos

Baryon-baryon elastic scattering is considered in the independent scattering (Landshoff) mechanism. It is suggested that for scattering at moderate energies, direct and interchange quark channels contribute with equal color coefficients because the quark color is randomized by soft gluon exchange during the hadronization stage. With this assumption, it is sh

Tomasz Skwarnicki

Importance of studies of $b$ quark decays and experimental status of various measurements are discussed.

Johan Linde, Håkan Snellman

We analyze the axial-vector form factors of the nucleon hyperon system in a model with mass dependent quark spin polarizations. This mass dependence is deduced from an earlier analysis\cite{jlhs,jlhs2} of magnetic moment data, and implies that the spin contributions from the quarks to a baryon decrease with the mass of the baryon. When applied to the axial-v

M. Fiolhais, B. Golli, M. Rosina, S. Sirca

The number of pions in the nucleon is a theoretical concept and its value is model dependent. It is, however, a useful tool to understand the pionic contribution to several nucleon observables such as electric charge radii, magnetic moments, axial charge, pion-nucleon coupling constant, amplitudes for electroexcitation of baryon resonances and electroproduct

M. Fiolhais, B. Golli, S. Sirca

We compute the amplitudes for the electromagnetic $γ_v N \to Δ$ transition in the framework of soliton models with quarks and mesons. The ratios E2/M1 and C2/M1 as functions of the photon four-momentum squared are dominated by the contribution of the pion cloud and are in reasonable agreement with the available experimental data.

S. Sahu, V. B. Semikoz, J. W. F. Valle

We consider resonant neutrino conversions in magnetised matter, such as a degenerate electron gas. We show how magnetisation effects caused by axial vector interactions of neutrinos with the charged leptons in the medium can induce a new type of resonant neutrino conversion which may occur even in situations where the MSW effect does not occur, such as the c

K. S. Babu, S. M. Barr

In a recent paper a model of quark and lepton masses was proposed. Without any family symmetries almost all the qualitative and quantitative features of the quark and lepton masses and Kobayashi-Maskawa mixing angles are explained, primarily as consequences of various aspects of $SO(10)$ symmetry. Here the model is discussed in much greater detail. The three

Riccardo Barbieri, George Dvali, Lawrence Hall

In a generic supersymmetric extension of the Standard Model, whether unified or not, a simple and well motivated U(2) symmetry, acting on the lightest two generations, completely solves the flavour changing problem and necessarily leads to a predictive texture for the Yukawa couplings.

T. Kurimoto, A. Tomita, S. Wakaizumi

The right-handed charged current gauge boson $W_R$ can affect significantly on the determination of the $CP$ violation angles to be measured at $B$ factories if the right-handed current quark mixing matrix $V^R$ is taken to a specific form to satisfy the bounds by neutral $K$ meson systems. The $W_R$ contribution can be sizable in $B^0$-$\overline{B^0}$ mixi

N. N. Khuri

We show that, even for a soft collision like forward elastic scattering, the phase of the amplitude is extremely sensitive to a breakdown of strict causality in local QFT. This is especially the case when the breakdown is manifested by a failure of polynomial boundedness which leads to amplitudes that in some complex direction have order 1 exponential growth

Sara Collins, Robert G. Edwards, Urs M. Heller, John Sloan

We present preliminary results of light hadron spectroscopy using valence, tadpole-improved, Clover fermions on an ensemble of gauge configurations generated with 2 flavors of staggered fermions at a beta of 5.6. We compare the slope and intercept of the curve M_V vs. M_PS^2 for Clover and Wilson fermions. We show that a higher order chiral perturbation theo

Sara Collins, Robert G. Edwards, Urs M. Heller, John Sloan

We calculate spin averaged splittings in the bottomonium and charmonium systems using the clover action. We compare static and kinetic masses of heavy-heavy and heavy-light mesons and discuss the consistency of the results.

Fritz DeJongh

We summarize Run I results relevant to an analysis of the CP asymmetry in $B\to J/ψK_s$, the CDF upgrade plans for Run II, and some of the main $B$ physics goals related to the exploration of the origin of CP violation.

S. Abachi

We report on a search for right-handed $W$ bosons ($W_R$). We used data collected with the DØ detector at the Fermilab Tevatron $p\bar p$ collider at $\sqrt{s}=$1.8 TeV to search for $W_R$ decays into an electron and a massive right-handed neutrino $W_R^\pm \to e^\pm N_R$. Using the inclusive electron data, we set mass limits independent of the $N_R$ decay:

Giorgio Immirzi

A discretized version of canonical gravity in (3+1)-d introduced in a previous paper is further developed, introducing the Liouville form and the Poisson brackets, and studying them in detail in an explicit parametrization that shows the nature of the variables when the second class constraints are imposed. It is then shown that, even leaving aside the diffi

Brien C. Nolan

The approach to asymptotic electromagnetic fields introduced by Goldberg and Kerr is used to study various aspects of Lorentz Covariant Gravity. Retarded multipole moments of the source, the central objects of this study, are defined, and a sequence of conservation equations for these are derived. These equations are used extensively throughout the paper. Th

John Lott

We give results on the following questions about a topologically tame hyperbolic 3-manifold M : 1. Does M have nonzero square-integrable harmonic 1-forms? 2. Does zero lie in the spectrum of the Laplacian acting on (1-forms on M)/Ker(d)?

C. Monthus, G. Oshanin, A. Comtet, S. F. Burlatsky

We study the sample-size dependence of the ground-state energy in a one-dimensional localization problem, based on a supersymmetric quantum mechanical Hamiltonian with random Gaussian potential. We determine, in the form of bounds, the precise form of this dependence and show that the disorder-average ground-state energy decreases with an increase of the siz

Yaroslav M. Blanter, Gerd Schoen

A system of two parallel Josephson junction arrays coupled by interlayer capacitances is considered in the situation where one layer is in the vortex-dominated and the other in the charge-dominated regime. This system shows a symmetry (duality) of the relevant degrees of freedom, i.e. the vortices in one layer and the charges in the other. In contrast to sin

Francois David, Thierry Jolicoeur

We study the phase transitions of N-components generalized helimagnets that obey the symmetry breaking pattern O(N) x O(N-1) -> O(N-1)_diag . In the neighborhood of two dimensions, a D=2+epsilon renormalization group study reveals a rich fixed point structure as well as a nematic-like phase with partial spin ordering. In the physical case O(3) x O(2) -> O(2)

F. Mazzanti, J. Boronat, A. Polls

A study of Final State Effects (FSE) on the dynamic structure function of superfluid $^4$He in the Gersch--Rodriguez formalism is presented. The main ingredients needed in the calculation are the momentum distribution and the semidiagonal two--body density matrix. The influence of these ground state quantities on the FSE is analyzed. A variational form of $ρ

R. J. Radtke, S. Das Sarma

We investigate the intersubband spin-density-excitation spectrum of a double quantum well in a low-density symmetry-broken phase with interwell antiferromagnetic correlations. This spectrum is related to the intensity measured in depolarized inelastic light scattering (ILS) experiments and therefore provides a means of empirically identifying the antiferroma

Yoshihiko Nonomura

The two-dimensional $S=1/2$ asymmetric Heisenberg Mattis model is investigated with the exact diagonalization of finite clusters. The Néel order parameter and the spin glass order parameter can be smoothly extrapolated to the thermodynamic limit in the antiferromagnetic region, as in the pure Heisenberg antiferromagnet. The critical concentration of the Néel

G. Wellein, H. Röder, H. Fehske

The Holstein Hubbard and Holstein t--J models are studied for a wide range of phonon frequencies, electron--electron and electron--phonon interaction strengths on finite lattices with up to ten sites by means of direct Lanczos diagonalization. Previously the necessary truncation of the phononic Hilbert space caused serious limitations to either very small sy

Karen Sparck Jones

Given the present state of work in natural language processing, this address argues first, that advance in both science and applications requires a revival of concern about what language is about, broadly speaking the world; and second, that an attack on the summarising task, which is made ever more important by the growth of electronic text resources and re

Matthew B. Kennel

Information in the time distribution of points in a state space reconstructed from observed data yields a test for ``nonstationarity&#39;&#39;. Framed in terms of a statistical hypothesis test, this numerical algorithm can discern whether some underlying slow changes in parameters have taken place. The method examines a fundamental object in nonlinear dynami

C. Alcock, R. A. Allsman, T. S. Axelrod, D. P. Bennett

We report the detection of 45 candidate microlensing events in fields toward the Galactic bulge. These come from the analysis of 24 fields containing 12.6 million stars observed for 190 days in 1993. Many of these events are of extremely high signal to noise and are remarkable examples of gravitational microlensing. The distribution of peak magnifications is

Ya. N. Istomin, V. I. Pariev

We investigate the linear stability of a hydrodynamic relativistic flow of magnetized plasma in the force--free approximation. We considered the case of light cylindrical jet in cold and dense environment, so the jet boundary remains at rest. Continuous and discrete spectra of frequencies are investigated analytically. An infinite sequence of eigenfrequencie

H. -Th. Janka, M. Ruffert

We perform three-dimensional hydrodynamical simulations of the coalescence of binary neutron stars. We include the emission and backreaction of gravitational waves into the Newtonian ``Piecewise Parabolic Method&#39;&#39;. The use of the physical equation of state of Lattimer & Swesty (1991) allows us to take into account the production of neutrinos. We eval

Eva K. Grebel, Wm James Roberts, Wolfgang Brandner

The young SMC cluster NGC 330 contains a number of blue stars that lie above the main-sequence turnoff found from our isochrone fitting and below the position of the blue supergiants. We used our own, new spectroscopy and published data on these stars to investigate their possible nature. Problems in interpreting the evolutionary status of the blue giants ha

J. Richard Bond, Lev Kofman, Dmitri Pogosyan

Observations indicate galaxies are distributed in a filament-dominated web-like structure. Numerical experiments at high and low redshift of viable structure formation theories also show filament-dominance. We present a simple quantitative explanation of why this is so, showing that the final-state web is actually present in embryonic form in the overdensity

Jan Stevens

We give more or less explicit equations for all two-dimensional cusp singularities of embedding dimension at least 4. They are closely related to Felix Klein&#39;s equations for universal curves with level n structure. The main technical result is a description of the versal deformation of an n-gon in $P^{n-1}$. The final section contains the equations for s

Gerard Jungman, Marc Kamionkowski, Arthur Kosowsky, David N. Spergel

The angular power spectrum of the cosmic microwave background (CMB) contains information on virtually all cosmological parameters of interest, including the geometry of the Universe ($Ω$), the baryon density, the Hubble constant ($h$), the cosmological constant ($Λ$), the number of light neutrinos, the ionization history, and the amplitudes and spectral indi

A. V. Belitsky, O. V. Teryaev

We analyze the singlet axial form factor of the proton for small momentum transferred in the framework of QCD sum rules using the interpolating nucleon current which explicitly accounts for the gluonic degrees of freedom. As a result we come to the quantitative description of the singlet axial constant: G_A(0)=0.2. The bilocal power corrections play the most

Andrew Gould, David H. Weinberg

We show that it is now possible to image optically thick $\lya$ clouds in fluorescent $\lya$ emission with a relatively long ($\sim 20 $hr) integration on a large ($\sim 10 $m) telescope. For a broad range of column densities ($N\gsim 10^{18.5} \cm^{-2}$), the flux of $\lya$ photons from recombination cascades is equal to $\sim 0.6$ times the flux of ionizin

P. L. Anthony, R. Becker-Szendy, P. E. Bosted, M. Cavalli-Sforza

In 1953, Ter-Mikaelian predicted that the bremsstrahlung of low energy photons in a medium is suppressed because of interactions between the produced photon and the electrons in the medium. This suppression occurs because the emission takes place over on a long distance scale, allowing for destructive interference between different instantaneous photon emiss

K. Z. Stanek

Recently Wo\'zniak \& Stanek (1996) proposed a new method to investigate interstellar extinction, based on two band photometry, which uses red clump stars as a means to construct the reddening curve. I apply this method to the color-magnitude diagrams obtained by the Optical Gravitational Lensing Experiment (OGLE) to construct an extinction map of $(40')^2 $

Yu. B. Suris

Discretizations of the Bogoyavlensky lattices are introduced, belonging to the same hierarchies as the continuous--time systems. The construction exemplifies the general scheme for integrable discretization of systems on Lie algebras with $r$--matrix Poisson brackets. An initial value problem for the difference equations is solved in terms of a factorization

Ingo Gaida

Global N=2 supersymmetry in four dimensions with a gauged central charge is formulated in superspace. To find an irreducible representation of supersymmetry for the gauge connections a set of constraints is given. Then the Bianchi identities are solved subject to this set of constraints. It is shown that the gauge connection of the central charge is a N=2 ve

M. Mekhfi

We investigate the internal space of Bessel functions which is associated to the group Z of positive and negative integers defining their orders. As a result we propose and prove a new unifying formula (to be added to the huge literature on Bessel functions) generating Bessel functions of real orders out of integer order one&#39;s. The unifying formula is ex

A. Punnoose, H. -P. Eckle, R. A. Römer

We study interacting one dimensional (1D) quantum lattice gases with integrable impurities. These model Hamiltonians can be derived using the quantum inverse scattering method for inhomogeneous models and are by construction integrable. Absence of backscattering at the impurities is shown to be the characteristic feature of these disordered systems. The valu

P. Baird, J. C. Wood

We construct large families of harmonic morphisms which are holomorphic with respect to Hermitian structures by finding heierarchies of Weierstrass-type representations. This enables us to find new examples of complex-valued harmonic morphisms from Euclidean spaces and spheres.

Dileep P. Jatkar, Sudipta Mukherji, Sudhakar Panda

We study some features of dyonic Black hole solution in heterotic string theory on a six torus. This solution has 58 parameters. Of these, 28 parameters denote the electric charge of the black hole, another 28 correspond to the magnetic charge, and the other two parameters being the mass and the angular momentum of the black hole. We discuss the extremal lim

Zurab Kakushadze, S. -H. Henry Tye

We generalize the rules for the free fermionic string construction to include other asymmetric orbifolds. Examples are given to illustrate the use of these rules.

H. F. Dowker, J. P. Gauntlett, G. W. Gibbons, G. T. Horowitz

We construct a solution to the low-energy string equations of motion in five dimensions that describes a circular loop of fundamental string exponentially expanding in a background electric $H$-field. Euclideanising this gives an instanton for the creation of a loop of fundamental string in a background $H$-field, and we calculate the rate of nucleation. Sol

Tsafrir Kolatt, Avishai Dekel

The power spectrum (PS) of mass density fluctuations, in the range $0.05 \leq k \leq 0.2 \ihmpc$, is derived from the Mark III catalog of peculiar velocities of galaxies, independent of ``biasing&#34;. It is computed from the density field as recovered by POTENT with Gaussian smoothing of $12\hmpc$, within a sphere of radius $\sim 60\hmpc$ about the Local Gr

Andrzej Czarnecki, Bernd Krause, William J. Marciano

The bosonic two-loop electroweak radiative corrections to the muon&#39;s anomalous magnetic moment, $a_μ\equiv (g_μ-2)/2$, are presented. We find $Δa_μ^{\rm EW}({\rm 2\,loop\, bosonic})/ a_μ^{\rm EW}({\rm 1\,loop})\approx {α\over π}\left(-3.6 \ln\left({M_W^2\over m_μ^2}\right) +0.10 \right)\approx -0.11$ for $M_{\rm Higgs}\approx 250$ GeV. Combining that res

Cristina Manuel

Classical transport theory is used to study the response of a non-Abelian plasma at zero temperature and high chemical potential to weak color electromagnetic fields. In this article the parallelism between the transport phenomena occurring in a non-Abelian plasma at high temperature and high density is stressed. Particularly, it is shown that at high densit

C. Glenn Boyd, Richard F. Lebed

We construct model-independent parametrizations of the individual QCD form factors relevant to Lambda_b --> Lambda_c l nu decays. These results follow from dispersion relations and analyticity, and incorporate an improvement in the technique that reduces the number of necessary parameters. To describe most form factors with 5%--10% accuracy over the entire k

Marc de Montigny

The method of graded contractions, based on the preservation of the automorphisms of finite order, is applied to the affine Kac-Moody algebras and their representations, to yield a new class of infinite dimensional Lie algebras and representations. After the introduction of the horizontal and vertical gradings, and the algorithm to find the horizontal toroid

M. Bordemann, M. Brischle, C. Emmrich, S. Waldmann

Based on a closed formula for a star product of Wick type on $\CP^n$, which has been discovered in an earlier article of the authors, we explicitly construct a subalgebra of the formal star-algebra (with coefficients contained in the uniformly dense subspace of representative functions with respect to the canonical action of the unitary group) that consists

Piotr Kosinski, Pawel Maslanka

The $κ-$Poincare group and its algebra in an arbitrary basis are constructed. The $κ-$de\-formation of the Weyl group and its algebra in any dimensions and in the reference frame in which $g_{00}=0$ are discussed.

M. Chaichian, P. P. Kulish

The meaning of quantum group transformation properties is discussed in some detail by comparing the (co)actions of the quantum group with those of the corresponding Lie group, both of which have the same algebraic (matrix) form of the transformation. Various algebras are considered which are covariant with respect to the quantum (super) groups $SU_q(2),\; SU

Volker Koch

These lectures are an attempt to a pedagogical introduction into the elementary concepts of chiral symmetry in nuclear physics. Effective chiral models such as the linear and nonlinear sigma model will be discussed as well as the essential ideas of chiral perturbation theory. Some applications to the physics of ultrarelativistic heavy ion collisions will be

Subal Das Gupta, Jicai Pan

The recent fragmentation data for central collisions of Gold on Gold are even qualitatively different from those for central collisions of Argon on Scandium. The latter can be fitted with a lattice gas model calculation. Effort is made to understand why the model fails for Gold on Gold. The calculation suggests that the large Coulomb interaction which is ope

N. J. Cerf

We present a novel quantum Monte Carlo method based on a path integral in Fock space, which allows to compute finite-temperature properties of a many-body nuclear system with a monopole pairing interaction in the canonical ensemble. It enables an exact calculation of the thermodynamic variables such as the internal energy, the entropy, or the specific heat,

Khazret S. Nirov

The relationship between various methods to calculate the physical degrees of freedom for gauge invariant systems of a general form is established. The set of hidden parameters caused for the superfluous degrees of freedom is revealed.

I. Ya. Arefeva, A. P. Zubarev

In this talk results of study in various dimensions of the Boltzmann master field for a subclass of planar diagrams, so called half-planar diagrams, found in the recent work by Accardi, Volovich and one of us (I.A.) are presented.

Taksu Cheon, Takaomi Shigehara

We examine the quantum energy levels of rectangular billiards with a pointlike scatterer in one and two dimensions. By varying the location and the strength of the scatterer, we systematically find diabolical degeneracies among various levels. The associated Berry phase is illustrated, and the existence of localized wave functions is pointed out. In one dime

A. Della Selva, J. Magnin, L. Masperi

A reexamination of the semiclassical approach of the relativistic electron indicates a possible variation of its helicity for electric and magnetic static fields applied along its global motion due to zitterbewegung effects, proportional to the anomalous part of the magnetic moment.

Taksu Cheon, Takaomi Shigehara

We argue that the random-matrix like energy spectra found in pseudointegrable billiards with pointlike scatterers are related to the quantum violation of scale invariance of classical analogue system. It is shown that the behavior of the running coupling constant explains the key characteristics of the level statistics of pseudointegrable billiards.

H. Itoyama, A. Morozov

Some basic facts about the prepotential in the SW/Whitham theory are presented. Consideration begins from the abstract theory of quasiclassical $τ$-functions , which uses as input a family of complex spectral curves with a meromorphic differential $dS$, subject to the constraint $\partial dS/\partial(moduli)= \ holomorphic$, and gives as an output a homogene

B. N. Bakalov, L. S. Georgiev, I. T. Todorov

W_{1+infty} is defined as an infinite dimensional Lie algebra spanned by the unit operator and the Laurent modes of a series of local quasiprimary chiral fields V^l(z) of dimension l+1 (l=0,1,2,...). These fields are neutral with respect to the u(1) current J(z)=V^0(z); as a result the (l+2)-fold commutator of J with V^l vanishes. We outline a construction o