February 1997 arXiv papers — page 10

Yun Wang, Edwin L. Turner

We study strong gravitational lensing by spiral galaxies, modeling them as infinitely thin uniform disks embedded in singular isothermal spheres. We derive general properties of the critical curves and caustics analytically. The multiple-image cross section is a sensitive function of the inclination angle of the disk relative to the observer. We compute the

Kenji Kajiwara, Kazushi Yamamoto, Yasuhiro Ohta

The rational solutions for the discrete Painlevé II equation are constructed based on the bilinear formalism. It is shown that they are expressed by the determinant whose entries are given by the Laguerre polynomials. Continuous limit to the Devisme polynomial representation of the rational solutions for the Painlevé II equation is also discussed.

Silviu Olariu

This work analyzes the effects of shielding on the Aharonov-Bohm scattering of electrons endowed with spin. The interaction of polarized electrons with bare and shielded magnetic strings is studied with the aid of the Dirac equation. It is found that the difference between the amplitudes for the scattering by bare and shielded strings of incident wave packet

Silviu Olariu

This work studies the interference of electrons in the presence of a line of magnetic flux surrounded by a normal-conducting mesoscopic cylinder at low temperature. It is found that, while there is a supplementary phase contribution from each electron of the mesoscopic cylinder, the sum of these individual supplementary phases is equal to zero, so that the p

John C. Baez, James Dolan

We give a definition of weak n-categories based on the theory of operads. We work with operads having an arbitrary set S of types, or `S-operads', and given such an operad O, we denote its set of operations by elt(O). Then for any S-operad O there is an elt(O)-operad O+ whose algebras are S-operads over O. Letting I be the initial operad with a one-eleme

Boris Shoikhet

We compare two approaches to the calculation of irreducible characters of the Lie algebra gl(infinity)^ with negative integral central charge. As a consequence, we obtain a "reciprocity formula" for Clebsch-Gordan coefficients, in the limit when the central charge tends to infinity.

Zhen Cao, Rudolph C. Hwa

In problems where the temporal evolution of a nonlinear system cannot be followed, a method for studying the fluctuations of spatial patterns has been developed. That method is applied to well-known problems in deterministic chaos (the logistic map and the Lorenz model) to check its effectiveness in characterizing the dynamical behaviors. It is found that th

G. Q. Li, G. E. Brown, C. -H. Lee, C. M. Ko

Nucleon flow in Au+Au collisions at 1 GeV/nucleon region and dilepton spectra in S+Au collisions at SPS energies are analysed in the relativistic transport model. They are shown to be sensitive to the nucleon vector and scalar potentials, respectively, and are thus useful probes of these potentials in dense matter. A recently developed effective Lagrangian w

Silviu Olariu, James J. Carroll, Carl B. Collins

We show that the emission of a gamma-ray photon by a nucleus can be influenced by a microwave magnetic field acting on the atomic electrons. We study theoretically these electron-nuclear double transitions (ENDTs) for ^{151}Eu nuclei in a CaF_2 lattice at low temperature, in the presence of a static magnetic field and of a microwave magnetic field. The ENDTs

H. Lu, C. N. Pope

We review an approach to the construction and classification of p-brane solitons in arbitrary dimensions, with an emphasis on those that arise in toroidally-compactified M-theory. Procedures for constructing the low-energy supergravity limits in arbitrary dimensions, and for studying the supersymmetry properties of the solitons are presented. Wide classes of

P. Saltsidis

The quantization of the tensionless p-brane is discussed. Inspection of the constraint algebra reveals that the central extensions for the p-branes have a simple form. Using a Hamiltonian BRST scheme we find that the quantization is consistent in any space-time dimension while the quantization of the conformal tensionless p-brane gives a critical dimension $

L. P. Horwitz

It is shown that the measurement algebra of Schwinger, a characterization of the properties of Pauli measurements of the first and second kinds, forming the foundation of his formulation of quantum mechanics over the complex field, has a quaternionic generalization. In this quaternionic measurement algebra some of the notions of quaternionic quantum mechanic

I. Ya. Aref'eva, M. G. Ivanov, I. V. Volovich

Non-extremal intersecting p-brane solutions of gravity coupled with several antisymmetric fields and dilatons in various space-time dimensions are constructed. The construction uses the same algebraic method of finding solutions as in the extremal case and a modified "no-force" conditions. We justify the "deformation" prescription. It is show

M. Z. Iofa, and L. A. Pando Zayas

Within the framework of "anomalously gauged" Wess-Zumino-Witten (WZW) models, we construct solutions which include nonabelian fields. Both compact and noncompact groups are discussed. In the case of compact groups, as an example of background containing nonabelian fields, we discuss conformal theory on the $SO(4)/SO(3)$ coset, which is the natural ge

Stuart Raby

Gauge-mediated SUSY breaking with a messenger scale of order $10^{15}$ GeV has some interesting features. It can solve the flavor changing neutral current problem of supersymmetric models with predictions for superpartner masses which are identical to those of minimal supergravity models. It can however also lead to theories with novel experimental signature

G. L. Fogli, E. Lisi, G. Scioscia

We reanalyze the recent data from the Liquid Scintillator Neutrino Detector (LSND) experiment, that might indicate anti-nu_mu<--->anti-nu_e mixing. This indication is not completely excluded by the negative results of established accelerator and reactor neutrino oscillation searches. We quantify the region of compatibility by means of a thorough statistical

A. Hosaka, D. Jido, M. Oka

The πNN^* and ηNN^* coupling constants are studied in the QCD sum rule ($N^* \equiv N(1535)). We investigate the two point functions between the vacuum and a one meson state in the soft meson limit. The operator product expansion is explicitly performed up to terms of dimension eight. We find that \gpNR vanishes to this order, while \geNR has a finite contri

M. Yoshimura

Quantum dynamics of a finite degrees of freedom is often much affected by interaction with the larger environment of cosmic medium. In this lecture we first review some recent developments of the theory of quantum dissipation in the linear open system. In the second part we discuss two classes of applications: decay of unstable particle in medium, and enviro

M. Campostrini, A. Pelissetto, P. Rossi, E. Vicari

We investigate the relation between on-shell and zero-momentum non-perturbative quantities entering the parametrization of the two-point Green&#39;s function of two-dimensional non-linear O(N) sigma models. We present accurate estimates of ratios of mass-scales and renormalization constants, obtained by an analysis of the strong-coupling expansion of the two

F. Abe

We have used 106 pb^-1 of data collected with the Collider Detector at Fermilab to search for new particles decaying to dijets. We exclude at the 95% confidence level models containing the following new particles: axigluons and flavor universal colorons with mass between 200 and 980 GeV/c, excited quarks with mass between 80 and 570 GeV/c^2 and between 580 a

Arvind Borde, Alex Vilenkin

We argue that many future-eternal inflating spacetimes are likely to violate the weak energy condition. It is possible that such spacetimes may not enforce any of the known averaged conditions either. If this is indeed the case, it may open the door to constructing non-singular, past-eternal inflating cosmologies. Simple non-singular models are, however, uns

A. V. Balatsky, M. I. Salkola

Reply to the comment by D.N. Aristov and A.G. Yashenkin (cond-mat/9612245) on PRL by Balatsky and Salkola (Phys. Rev. Lett., V76, 2386, (1996), cond-mat/9602034).

M. Posternak, A. Baldereschi, H. Krakauer, R. Resta

We calculate ab-initio the electronic states and the Born dynamical charge Z* of the alkaline-earth oxides in the local-density approximation. We investigate the trend of increasing Z* values through the series, using band-by-band decompositions and computational experiments performed on fake materials with artificially-modified covalence. The deviations of

S. V. Buldyrev, L. A. N. Amaral, S. Havlin, H. Leschhorn

In the preceding paper we presented empirical results describing the growth of publicly-traded United States manufacturing firms within the years 1974--1993. Our results suggest that the data can be described by a scaling approach. Here, we propose models that may lead to some insight into these phenomena. First, we study a model in which the growth rate of

Klaus Frahm, Axel Mueller-Groeling, Jean-Louis Pichard, Dietmar Weinmann

In a recent letter [Phys. Rev. Lett. 78, 515 (1997); cond-mat/9612034] Roemer and Schreiber report on numerical calculations that led them to conclude that the previously observed enhancement of the localization length $L_2$ of two interacting particles (TIP) vanishes in the thermodynamic limit. We point out that such a claim (i) is in conflict with the scal

Holger Frahm, Claus Rödenbeck

We study zero temperature properties of a system of two coupled quantum spin chains subject to fields explicitly breaking time reversal symmetry and parity. Suitable choice of the strength of these fields gives a model soluble by Bethe Ansatz methods which allows to determine the complete magnetic phase diagram of the system and the asymptotics of correlatio

L. A. N. Amaral, S. V. Buldyrev, S. Havlin, H. Leschhorn

We address the question of the growth of firm size. To this end, we analyze the Compustat data base comprising all publicly-traded United States manufacturing firms within the years 1974-1993. We find that the distribution of firm sizes remains stable for the 20 years we study, i.e., the mean value and standard deviation remain approximately constant. We stu

Michele Fabrizio, Alexander O. Gogolin

In a recent Physical Review Letter, Oreg and Finkel&#39;stein (OF) have calculated the electron density of states (DOS) for tunneling into a repulsive Luttinger liquid close to the location of an impurity. The result of their calculation is a DOS which is enhanced with respect to the pure system, and moreover diverging for not too strong repulsion. In this C

Michele Fabrizio, Erio Tosatti

Narrow-band conductors may turn insulating and magnetic as a consequence of strong electron-electron correlation. In molecular conductors, the concomitance of a strong Jahn-Teller coupling may give rise to the alternative possibility of a non-magnetic insulator, with or without a static cooperative Jahn-Teller distortion. In the latter case the insulator has

Maura Sassetti, Bernhard Kramer

The non linear charge transfer through a tunnel junction between two Luttinger systems is studied for repulsive, finite range interaction between electrons on the same, V_{11}, and on different,V_{12}, sides of the junction. Features of the Coulomb blockade effect are observed if V_{12}=0. We predict a novel interaction induced enhancement of the current if

R. Rajaraman

We present a field theory of Jain&#39;s composite fermion model as generalised to the bilayer quantum Hall systems. We define operators which create composite fermions and write the Hamiltonian exactly in terms of these operators. This is seen to be a complexified version of the familiar Chern Simons theory. In the mean-field approximation, the composite fer

F. Y. Wu

Duality relations are obtained for correlation functions of the q-state Potts model on any planar lattice or graph using a simple graphical analysis. For the two-point correlation we show that the correlation length is precisely the surface tension of the dual model, generalizing a result known to hold for the Ising model. For the three-point correlation an

Hamish Cunningham, Kevin Humphreys, Robert Gaizauskas, Yorick Wilks

We classify and review current approaches to software infrastructure for research, development and delivery of NLP systems. The task is motivated by a discussion of current trends in the field of NLP and Language Engineering. We describe a system called GATE (a General Architecture for Text Engineering) that provides a software infrastructure on top of which

Wojciech Skut, Brigitte Krenn, Thorsten Brants, Hans Uszkoreit

We describe an annotation scheme and a tool developed for creating linguistically annotated corpora for non-configurational languages. Since the requirements for such a formalism differ from those posited for configurational languages, several features have been added, influencing the architecture of the scheme. The resulting scheme reflects a stratification

R. van Zon, Th. W. Ruijgrok

Some of the subtleties of the integrability of the elliptic quantum billiard are discussed. A well known classical constant of the motion has in the quantum case an ill-defined commutator with the Hamiltonian. It is shown how this problem can be solved. A geometric picture is given revealing why levels of a separable system cross. It is shown that the repuls

Beverly J. Smith, Curt Struck, Richard W. Pogge

We present high spatial resolution 21 cm HI maps of the interacting galaxy pair NGC 7714/7715. We detect a massive (2 x 10**9 M(sun)) HI bridge connecting the galaxies that is parallel to but offset from the stellar bridge. A chain of HII regions traces the gaseous bridge, with H-alpha peaks near but not on the HI maxima. An HI tidal tail is also detected to

A. A. Esin, J. E. McClintock, R. Narayan

We present a model for the high-low state transition of the X-Ray Nova GS 1124-68 (Nova Muscae 1991) observed by Ginga. The model consists of an advection-dominated accretion flow (ADAF) near the central black hole surrounded by a thin accretion disk. During the rise phase of the outburst, as the mass accretion rate increases, the transition radius between t

J. M. Colberg, S. D. M. White, A. Jenkins, F. R. Pearce

We report on work done by the Virgo consortium, an international collaboration set up in order to study the formation and evolution of Large Scale Structure using N-body simulations on the latest generation of parallel supercomputers. We show results of 256^3 particle simulations of the formation of clusters in four Dark Matter models with different cosmolog

N. W. Evans, J. L. Collett

An origin is sought for the ubiquity of cusps, both in computer simulations of halo formation in hierarchical clustering cosmogonies and in observations of galactic nuclei by the Hubble Space Telescope (HST). The encounters of merging clumps that built the galaxies can be described by the collisional Boltzmann equation. Using insights gained by studying the

A. Treves, F. Rovetti, Ph. Jetzer, C. M. Urry

PKS 2155-304 is the only BL Lac object for which well-sampled multiwavelength light curves resolve the intraday variability at UV and X-ray wavelengths. In particular we focus on the multifrequency campaign of November 1991, which showed a rather exceptional behaviour of the source exhibiting substantial achromatic variability from optical to X-ray wavelengt

Giuseppe Bono, Filippina Caputo, Santi Cassisi, Roberta Incerpi

We present a theoretical investigation on the pulsational behavior of metal-rich RR Lyrae variables over the range of evolutionary parameters suitable for stars with metallicities Z= 0.006, 0.01 and 0.02. With the addition of similar results for metal-poor pulsators we discuss the theoretical pulsational scenario covering the metallicity range from Z=0.0001

Shaun Cole, David H. Weinberg, Carlos S. Frenk, Bharat Ratra

We study the clustering of the mass distribution in COBE-normalized open and flat CDM models using large N-body simulations. With an age of the universe of 14 Gyr (12 Gyr) for the flat (open) models and a baryon density fixed by nucleosynthesis constraints, the observed abundance of rich galaxy clusters leads to tight constraints on the density parameter; 0.

Gerard Gilmore

A wealth of recent observational studies shows the dark matter in the Milky Way to have the following fundamental properties: 1) there is no detectable dark matter associated with the Galactic disk -- the dark matter is distributed in a purely halo distribution with local volume density near the Earth 0.3GeV/cc = 0.01Msun/pc3 2) The stellar mass function is

Tommy Wiklind, Francoise Combes, Christian Henkel, Friedrich Wyrowski

Interferometric observations of the CO(1-0) line in the elliptical galaxy NGC759 shows that it contains 2 10^9 Mo of molecular gas, confined to a circumnuclear ring with an average radius of only 650pc. The maximum gas surface density is 750 Mo/pc^2, which is comparable to the critical gas surface density for large scale gravitational instabilities. The low

Renyue Cen, Robert A. Simcoe

This study analyzes the sizes, shapes and correlations of $\lya$ clouds produced by a hydrodynamic simulation of a spatially flat CDM universe with a non-zero cosmological constant ($Ω_0=0.4$, $Λ_0=0.6$, $σ_8 =0.79$), over the redshift range $2\le z \le 4$. The $\lya$ clouds range in size from several kiloparsecs to about a hundred kiloparsecs in proper unit

Igor R. Klebanov

We calculate classical cross sections for absorption of massless scalars by the extremal 3-branes of type IIB theory, and by the extremal 2- and 5-branes of M-theory. The results are compared with corresponding calculations in the world volume effective theories. For all three cases we find agreement in the scaling with the energy and the number of coinciden

Saurya Das, Arundhati Dasgupta, Tapobrata Sarkar

We study the emission of scalar particles from a class of near-extremal five dimensional black holes and the corresponding D-brane configuration at high energies. We show that the distribution functions and the black hole greybody factors are modified in the high energy tail of the Hawking spectrum in such way that the emission rates exactly match. We extend

J. H. Han

It is shown that the conventional many-body techniques to calculate the Green&#39;s functions can be applied to the wide, compressible edge of a quantum Hall bar. The only ansatz we need is the existence of stable density modes that yields a simple equation of motion of the density operators. We derive the spectral density at a finite temperature and show ho

S. A. Gurvitz

Starting with the many-body Schrödinger equation we derive new rate equations for resonant transport in quantum dots linked by ballistic channels with high density of states. The charging and the Pauli exclusion principle effects were taken into account. It is shown that the current in such a system displays quantum coherence effects, even if the dots are aw

Simon Davis

Some general remarks are made about the quantum theory of scalar fields and the definition of momentum in curved space. Special emphasis is given to field theory in anti-de Sitter space, as it represents a maximally symmetric space-time of constant curvature which could arise in the local description of matter interactions in small regions of space-time. Tra

Thomas Meissner

We exhibit the method for obtaining non perturbative quark and gluonic vacuum condensates from a model truncation of QCD. The truncation allows for a phenomenological description of the quark-quark interaction in a framework which maintains all global symmetries of QCD and allows an 1/N_c expansion. Within this approach the functional integration over the gl

J. A. Newbury, C. T. Russell, M. Gedalin

We determine a simple expression for the ramp width of a collisionless fast shock, based upon the relationship between the noncoplanar and main magnetic field components. By comparing this predicted width with that measured during an observation of a shock, the shock velocity can be determined from a single spacecraft. For a range of low-Mach, low-beta bow s

A M Semikhatov

There exist two different languages, the ^sl(2) and N=2 ones, to describe similar structures; a dictionary is given translating the key representation-theoretic terms related to the two algebras. The main tool to describe the structure of ^sl(2) and N=2 modules is provided by diagrams of extremal vectors. The ^sl(2) and N=2 representation theories of certain

Pavel Grozman, Dimitry Leites

We completely describe presentations of Lie superalgebras with Cartan matrix if they are simple Z-graded of polynomial growth. Such matrices can be neither integer nor symmetrizable. There are non-Serre relations encountered. In certain cases there are infinitely many relations. Our results are applicable to the Lie algebras with the same Cartan matrices as

Paul Mansfield, Marcos Sampaio, Jiannis Pachos

For slowly varying fields the vacuum functional of a quantum field theory may be expanded in terms of local functionals. This expansion satisfies its own form of the Schrödinger equation from which the expansion coefficents can be found. For scalar field theory in 1+1 dimensions we show that this approach correctly reproduces the short-distance properties as

M. Calixto, V. Aldaya, J. Guerrero

We provide the theoretic value 1/2 for the quantity $\sin**2θ_W=e**2/g**2$, as opposite to the experimental value of $\sin**2θ_W=1-M_W**2/M_Z**2 \sim 0.23$, in the electro-weak gauge group $SU(2)\otimes U(1)_Y$. The arguments we use are of topological nature and have to do with natural requirements of globality in the transformations of the gauge algebra. Th

S. T. West

A study is made of properties of the Z(3) interface which forms between the different ordered phases of pure SU(3) gauge theory above a critical temperature. The theory is simulated on a (2+1)-D lattice at various temperatures above this critical point. At high temperatures, the interface tension is shown to agree well with the prediction of perturbation the

W. Kob

We give a brief introduction to the mode-coupling theory of the glass transition, a theory which was proposed a while ago to describe the dynamics of supercooled liquids. After presenting the basic equations of the theory, we review some of its predictions and compare these with results of experiments and computer simulations. We conclude that the theory is

Marcelo Blatt, Shai Wiseman, Eytan Domany

We present a new approach to clustering, based on the physical properties of an inhomogeneous ferromagnet. No assumption is made regarding the underlying distribution of the data. We assign a Potts spin to each data point and introduce an interaction between neighboring points, whose strength is a decreasing function of the distance between the neighbors. Th

S. Vine, S. Sigurdsson

We present a hybrid technique of N-body simulation to deal with collisionless stellar systems having an inhomogeneous global structure. We combine a treecode and a self-consistent field code such that each of the codes model a different component of the system being investigated. The treecode is suited to treatment of dynamically cold or clumpy systems which

Johannes Huebschmann

We introduce a notion of duality for a Lie-Rinehart algebra giving certain bilinear pairings in its cohomology generalizing the usual notions of Poincaré duality in Lie algebra cohomology and de Rham cohomology. We show that the duality isomorphisms can be given by a cap product with a suitable fundamental class and hence may be taken natural in any reasonab

A. Kazarnovski-Krol

In this paper we prove that certain matrix elements of vertex operators of deformed W-algebra satisfy Macdonald difference equations and form n! -dimensional space of solutions. These solutions are the analogues of Harish Chandra solutions with prescribed asymptotic behavior. We obtain formulas for analytic continuation as a consequence of braiding propertie

Silviu Olariu, Agata Olariu, Valeriu Zoran

This is a paper about induced gamma emission. The X-ray electron-nuclear double transitions (XENDT) are processes in which a transition effected by an inner atomic electron takes place simultaneously with a nuclear electromagnetic transition. We give expressions for the cross sections of electric and magnetic XENDTs of various multipole orders. We calculate

W. A. Hofer

Neutron interference measurements with macroscopic beam separation allow to study the influence of magnetic fields on spin properties. By calculating the interaction energy with a dynamic and deterministic model, we are able to establish that the phase shift on one component of the neutron beam is linear with magnetic intensity, and equally, that interaction

Jim Stasheff

The Batalin-Vilkovisky master equations, both classical and quantum, are precisely the integrability equations for deformations of algebras and differential algebras respectively. This is not a coincidence; the Batalin-Vilkovisky approach is here translated into the language of deformation theory.

J. Maurice Rojas

We illustrate an efficient new method for handling polynomial systems with degenerate solution sets. In particular, a corollary of our techniques is a new algorithm to find an isolated point in every excess component of the zero set (over an algebraically closed field) of any $n$ by $n$ system of polynomial equations. Since we use the sparse resultant, we th

J. Maurice Rojas

This paper reexamines univariate reduction from a toric geometric point of view. We begin by constructing a binomial variant of the $u$-resultant and then retailor the generalized characteristic polynomial to fully exploit sparsity in the monomial structure of any given polynomial system. We thus obtain a fast new algorithm for univariate reduction and a bet

V. Aldaya, M. Calixto, J. Guerrero

Within the frame of a Group Approach to Quantization anomalies arise in a quite natural way. We present in this talk an analysis of the basic obstructions that can be found when we try to translate symmetries of the Newton equations to the Quantum Theory. They fall into two classes: algebraic and topologic according to the local or global character of the ob

O. Bergman, C. B. Thorn

In string-bit models, string is described as a polymer of point-like constituents. We attempt to use string-bit ideas to investigate how the size of string is affected by string interactions in a non-perturbative context. Lacking adequate methods to deal with the full complications of bit rearrangement interactions, we study instead a simplified analog model

Ashoke Sen

We establish the equivalence of the Gimon-Polchinski orientifold and F-theory on an elliptically fibered Calabi-Yau three fold on base $CP^1 \times CP^1$ by comparing the gauge symmetry breaking pattern, local deformations in the moduli space, as well as the axion-dilaton background in the weak coupling limit in the two theories. We also provide an explanati

Philippe de Forcrand

The increase with time of computer resources devoted to simulations of full QCD is spectacular. Yet the reduction of systematic errors is comparatively slow. This is due to the algorithmic complexity of the problem. I review, in elementary terms, the origin of this complexity, and estimate it for 3 exact fermion algorithms.

Adrian Patrascioiu, Erhard Seiler

We analyze the arguments put forward recently by Niedermayer et al in favor of the correctness of conventional perturbation theory in non-Abelian models and supposedly showing that our super-instanton counterexample was sick. We point out that within their own set of assumptions, the proof of Niedermayer et al regarding the correctness of perturbation theory

Steven Carlip

Black holes are thermodynamic objects, but despite recent progress, the ultimate statistical mechanical origin of black hole temperature and entropy remains mysterious. Here I summarize an approach in which the entropy is viewed as arising from ``would-be pure gauge&#39;&#39; degrees of freedom that become dynamical at the horizon. For the (2+1)-dimensional

Inger Jorgensen

Spectral line indices for a sample of 290 nearby E and S0 galaxies are used to investigate the stellar populations of these galaxies. Relations are established between the line indices (Mg2, <Fe>, Hbeta) and the velocity dispersions, the masses of the galaxies, the M/L ratios and the cluster environment. The difference between the slope of the Mg2-sigma rela

J. L. Friar, G. L. Payne

The electric polarizability and logarithmic mean-excitation energy are calculated for the deuteron using techniques introduced in atomic physics. These results are then used to improve limits on the atomic-deuterium frequency shift due to nuclear polarization in the unretarded dipole limit, as well as confirming previous results.

R. N. Mohapatra, S. Nandi

We propose a new class of gauge mediated supersymmetry breaking models where the standard model gauge group is embedded into the gauge group $SU(2)_L\times U(1)_{I_{3R}}\times U(1)_{B-L}$ [or $SU(2)_L\times SU(2)_R\times U(1)_{B-L}$] at the supersymmetry breaking scale $Λ_S$. The messenger sector in these models can consist of color singlet but $U(1)_{I_{3R}

Fusun Akman

We generalize the coupled braces {x}{y} of Gerstenhaber and {x}{y,...,z} of Getzler depicting compositions of multilinear maps in the Hochschild complex C(A)=Hom(TA;A) of a graded vector space A to expressions of the form {x,...,y}...{z,...,w} on the extended space Hom(TA;TA), and clarify many of the existing sign conventions that show up in the algebra of m

A. N. Kamal, C. W. Luo

The role of inelastic final state interactions in CP asymmetries is investigated in single isospin two-body hadronic decays of the B meson. We demonstrate that in a channel where the CP asymmetry vanishes in absence of inelastic final state interactions, a coupling to a second channel where the asymmetry is nonvanishing can result in an asymmetry in the firs

John N. Bahcall, Sarbani Basu, Pawan Kumar

Localized differences between the real sun and standard solar models are shown to be small. The sound speeds of the real and the standard model suns typically differ by less than 0.3% in the solar core.

I. V. Moskalenko, E. Jourdain

By solving the Fokker-Planck equation directly we examine effects of annihilation, particle escape and injection on the form of a steady-state positron distribution in thermal hydrogen plasmas with $kT<m_ec^2$. We show that the escape of positrons in the form of electron-positron pairs and/or pair plasma has an effect on the positron distribution causing, in

N. V. Mikheev, L. A. Vassilevskaya

The radiative decay of the axion $a \to γγ$ is investigated in an external electromagnetic field in DFSZ model in which axion couples to both quarks and leptons at tree level. The decay probability is strongly catalyzed by the external field, namely, the field removes the main suppression caused by the smallness of the axion mass.

H. O. Girotti, M. Gomes, V. O. Rivelles, A. J. da Silva

The continuous extension of the discrete duality symmetry of the Schwarz-Sen model is studied. The corresponding infinitesimal generator $Q$ turns out to be local, gauge invariant and metric independent. Furthermore, $Q$ commutes with all the conformal group generators. We also show that $Q$ is equivalent to the non---local duality transformation generator f

Naohisa Ogawa

This paper introduces the way of the embedding of spinning particle quantum mechanically. Schrödinger equation on its submanifold obtains the gauge field as spin connection, and it reduces to the ones obtained by Ohnuki and Kitakado when we consider $S^2$ in $R^3$. PACS numbers: 03.65

Naohisa Ogawa

Hamiltonian BRST formalism (FV formalism) includes many auxiliary fields without explanation. Its path-integration has a simple form by using BRST charge, but its construction is quite mechanically and hard to understand physical meaning. In this paper we perform the phase space path-integral with requiring BRST invariance for action and measure, and show th

Andrei Teleman

The goal of this article was the S^1-equivariant transversality-problem and the compactification-problem for the moduli spaces of (perturbed) PU(2)-monopoles. A substantially improved version entitled &#34;Moduli spaces of PU(2)-monopoles (revised version)&#34; which gives simpler, clearer proofs of the transversality results, has been published on arxiv in

I. Bojak, M. Ernst

We discuss several methods of calculating the DIS structure functions F_2(x,Q^2) based on BFKL-type small x resummations. Taking into account new HERA data ranging down to small x and low Q^2, the pure leading order BFKL-based approach is excluded. Other methods based on high energy factorization are closer to conventional renormalization group equations. De

S. Frixione, M. L. Mangano, P. Nason, G. Ridolfi

We review the present theoretical and experimental status of heavy quark production in high-energy collisions. In particular, we cover hadro- and photoproduction at fixed target experiments, at HERA and at the hadron colliders, as well as aspects of heavy quark production in e+e- collisions at the Z0 peak.

R. Benzi, L. Biferale, A. Wirth

An exact non-perturbative calculation of the fourth-order anomalous correction to the scaling behaviour of a random shell-model for passive scalars is presented. Importance of ultraviolet (UV) and infrared (IR) boundary conditions on the inertial scaling properties are determined. We find that anomalous behaviour is given by the null-space of the inertial op

D. Boer, R. Jakob, P. J. Mulders

We present the results of the tree-level calculation of inclusive two-hadron production in electron-positron annihilation via one photon up to subleading order in 1/Q. We consider the situation where the two hadrons belong to different, back-to-back jets. We include polarization of the produced hadrons and discuss azimuthal dependences of asymmetries. New as

Gerard van der Geer

In this paper we determine the structure of the Chow ring of the Delaunay-Voronoi compactification $\tilde{\cal A}_3$ of the moduli space of principally polarized abelian threefolds. This compactification was introduced by Namikawa and studied by Tsushima. We use equivariant classes on level coverings of $\tilde{\cal A}_3$. We also compare this ring with the

P. Exner, P. Šeba

We propose a model for scattering in a flat resonator with a thin antenna. The results are applied to rectangular microwave cavities. We compute the resonance spacing distribution and show that it agrees well with experimental data provided the antenna radius is much smaller than wavelengths of the resonance wavefunctions.

Paul Benioff

The generalized counting quantum Turing machine (GCQTM) is a machine which, for any N, enumerates the first $2^{N}$ integers in succession as binary strings. The generalization consists of associating a potential with read-1 steps only. The Landauer Resistance (LR) and band spectra were determined for the tight binding Hamiltonians associated with the GCQTM

Giovanni Costantini, Fabrizio Smeraldi

Quantum parallelism is the main feature of quantum computation. In 1985 D. Deutsch showed that a single quantum computation may be sufficient to state whether a two-valued function of a two-valued variable is constant or not. Though the generalized problem with unconstrained domain and range size admits no deterministic quantum solution, a fully probabilisti

E877 Collaboration, J. Barrette, R. Bellwied, S. Bennett

Two-particle correlation functions for positive and negative pions have been measured in Au+Au collisions at 10.8~GeV/c per nucleon. The data were analyzed using one- and three-dimensional correlation functions. From the results of the three-dimensional fit the phase space density of pions was calculated. It is consistent with local thermal equilibrium.

D. J. Millener

It is shown that differences, due to charge-dependent effects, in the 17N and 17Ne ground-state wave functions account for the fact that the experimentally measured branch for the beta+ decay of 17Ne to the first excited state of 17F is roughly a factor of two larger than expected on the basis of nuclear matrix elements which reproduce the corresponding beta

Y. Y. Sharon, L. Zamick, M. S. Fayache, G. Rosensteel

For a $Q \cdot Q$ interaction the energy weighted sum rule for isovector orbital magnetic dipole transitions is proportional to the difference $\sum B(E2, isoscalar) - \sum B(E2, isovector)$, not just to $\sum B(E2, physical)$. This fact is important in ensuring that one gets the correct limit as one goes to nuclei, some of which are far from stability, for

C. M. Ko, V. Koch, G. Li

This review is devoted to the discussion of hadron properties in the nuclear medium and its relation to the partial restoration of chiral symmetry. Special attention is given to disentangle in-medium effects due to conventional many-body interactions from those due to the change of the chiral condensate. In particular, we shall discuss medium effects on the

Graham A. Niblo, Lawrence Reeves

We show that groups satisfying Kazhdan&#39;s property (T) have no unbounded actions on finite dimensional CAT(0) cube complexes, and deduce that there is a locally CAT(-1) Riemannian manifold which is not homotopy equivalent to any finite dimensional, locally CAT(0) cube complex.

C. M. Hull

Effective actions are derived for (2,0) and (2,1) superstrings by studying the corresponding sigma-models. The geometry is a generalisation of Kahler geometry involving torsion and the field equations imply that the curvature with torsion is self-dual in four dimensions, or has SU(n,m) holonomy in other dimensions. The Yang-Mills fields are self-dual in four

Serguei B. Isakov, Jon Magne Leinaas, Jan Myrheim, Alexios P. Polychronakos

The algebra of observables for identical particles on a line is formulated starting from postulated basic commutation relations. A realization of this algebra in the Calogero model was previously known. New realizations are presented here in terms of differentiation operators and in terms of SU(N)-invariant observables of the Hermitian matrix models. Some pa