February 1996 arXiv papers — page 10

M. Inaba, H. Matsukawa, M. Saitoh, H. Fukuyama

The Néel and the singlet RVB orders of the {\it t-J} model in a 2D square lattice are studied in the slave-boson mean-field approximation. It is shown that the Néel order parameter takes the maximum value at the finite temperature and disappear at the lower temperature for a certain range of doping. It is also shown that the Néel and the singlet RVB orders c

Kazuo Hida

The density matrix renormalization group method is generalized to one dimensional random systems. Using this method, the energy gap distribution of the spin-1/2 random antiferromagnetic Heisenberg chain is calculated. The results are consistent with the predictions of the renormalization group theory demonstrating the effectiveness of the present method in r

Anton Bovier, Veronique Gayrard, Pierre Picco

We study a one-dimensional version of the Hopfield model with long, but finite range interactions below the critical temperature. In the thermodynamic limit we obtain large deviation estimates for the distribution of the ``local'' overlaps, the range of the interaction, $γ^{-1}$, being the large parameter. We show in particular that the local overlap

Raymond Kapral, Xiao-Guang Wu

An investigation of the mesoscopic dynamics of chemical systems whose mass action equation gives rise to a deterministic chaotic attractor is carried out. A reactive lattice-gas model for the three-variable autocatalator is used to provide a mesoscopic description of the dynamics. The global and local dynamics is studied as a function of system size and diff

J. A. Sellwood, Victor P. Debattista

A strong bar rotating within a massive halo should lose angular momentum to the halo through dynamical friction, as predicted by Weinberg. We have conducted fully self-consistent, numerical simulations of barred galaxy models with a live halo population and find that bars are indeed braked very rapidly. Specifically, we find that the bar slows sufficiently w

Gary Steigman

In the first thousand seconds of its evolution the Universe was a primordial nuclear reactor synthesizing the nuclides D, $^3$He, $^4$He and $^7$Li. These messengers from the Big Bang provide a unique window on the early, hot, dense Universe, offering the opportunity for tests of the standard models of particle physics and of cosmology. A new, statistically

Hui Li, Masaaki Kusunose, Edison Liang

We consider stochastic particle acceleration in plasmas around stellar mass black holes to explain the emissions above 1 MeV from Galactic black hole candidates. We show that for certain parameter regimes, electrons can overcome Coulomb losses and be accelerated beyond the thermal distribution to form a new population, whose distribution is broad and usually

E. M. de Gouveia Dal Pino, M. Birkinshaw, W. Benz

Most collimated supersonic protostellar jets show a collimated wiggling, and knotty structure (e.g., the Haro 6-5B jet) and frequently reveal a long gap between this structure and the terminal bow shock. In a few cases, there is no evidence of such a terminal feature. We present three-dimensional smoothed particle hydrodynamical simulations which suggest tha

P. Hoeflich, A. Khokkhlov

Theoretical monochromatic light curves and photospheric expansion velocities are compared with observations of 27 Type Ia supernovae (SNe Ia). A set of 37 models has been considered which encompasses all currently discussed explosion scenarios for Type Ia supernovae including deflagrations, detonations, delayed detonations, pulsating delayed detonations and

Miles Reid

This is a first graduate course in algebraic geometry. It aims to give the student a lift up into the subject at the research level, with lots of interesting topics taken from the classification of surfaces, and a human-oriented discussion of some of the technical foundations, but with no pretence at an exhaustive treatment. The early chapters introduce topi

Frank Sottile

We describe an approach to the question of finding real solutions to problems of enumerative geometry, in particular the question of whether a problem of enumerative geometry can have all of its solutions be real. We give some methods to infer one problem can have all of its solutions be real, given that a related problem does. These are used to show many Sc

José M Figueroa-O'Farrill, Takashi Kimura, Arkady Vaintrob

We compute the universal weight system for Vassiliev invariants coming from the Lie superalgebra gl(1|1) applying the construction of \cite{YB}. This weight system is a function from the space of chord diagrams to the center $Z$ of the universal enveloping algebra of gl(1|1), and we find a combinatorial expression for it in terms of the standard generators o

Jochen Fingberg, Janos Polonyi

SU(2) gauge theory with competing interactions is shown to possess a rich phase structure with anti-ferromagnetic vacua. It is argued that the phase boundaries persist in the weak coupling limit suggesting the existence of different renormalized continuum theories for QCD.

Pyungwon Ko, Jungil Lee, H. S. Song

Photoproduction of $J/ψ$ is considered including the color-octet contributions from the various partial wave states, $^{2S+1}L_J$ = $^1S_0$, $^3S_1$ and $^3P_J$. The production cross section depends on three new nonperturbative parameters defined in NRQCD, called the color-octet matrix elements. Using the color-octet matrix elements determined by fitting the

Giuseppe Dito, Moshe Flato, Daniel Sternheimer, Leon Takhtajan

Starting from deformation quantization (star-products), the quantization problem of Nambu Mechanics is investigated. After considering some impossibilities and pushing some analogies with field quantization, a solution to the quantization problem is presented in the novel approach of Zariski quantization of fields (observables, functions, in this case polyno

Renata Kallosh, Barak Kol

Extreme black holes with 1/8 of unbroken N=8 supersymmetry are characterized by the non-vanishing area of the horizon. The central charge matrix has four generic eigenvalues. The area is proportional to the square root of the invariant quartic form of $E_{7(7)}$. It vanishes in all cases when 1/4 or 1/2 of supersymmetry is unbroken. The supergravity non-reno

Wayne Hu, Martin White

We discuss a new test of inflation from the harmonic pattern of peaks in the cosmic microwave background radiation angular power spectrum. By characterizing the features of alternate models and revealing signatures essentially unique to inflation, we show that inflation could be validated by the next generation of experiments.

Wayne Hu, Martin White

We study the uniqueness and robustness of acoustic signatures in the cosmic microwave background by allowing for the possibility that they are generated by some as yet unknown source of gravitational perturbations. The acoustic {\it pattern} of peak locations and relative heights predicted by the standard inflationary cold dark matter model is essentially un

K. Tsushima, S. W. Huang, Amand Faessler

Parametrizations of total cross sections sufficient for all channels of the $πB \rightarrow Y K$ reactions are completed using a resonance model. As well as discussing the $πN \rightarrow ΛK$ reactions, which were not presented in our previous publications, we present the differential cross section for $πN \rightarrow ΛK$. This report also aims at presenting

Sergey Arkhipov

We describe semiinfinite cohomology of associative algebras in terms of Koszul (or bar) duality. Consider an associative algebra $A$ and two its subalgebras $B$ and $N$ such that $A=B\otimes N$ as a vector space. We prove that the endomorphism algebra of the semiregular $A$-module appears naturally in semiinfinite cohomology theory as a ``two times Koszul du

N. S. Erokhin, N. N. Zolnikova, M. J. Rycroft, D. Nunn

The influence of wave frequency variation on the anomalous cyclotron resonance $ω=ω_{Be}+kv_{\|}$ interaction (ACRI) of energetic electrons with a ducted finite amplitude whistler-mode wave propagating through the so-called transient plasma layer (TPL) in the magnetosphere or in the ionosphere is studied both analytically and numerically. The anomalous cyclo

S. E. Koonin, D. J. Dean, K. Langanke

We review quantum Monte Carlo methods for dealing with large shell model problems. These methods reduce the imaginary-time many-body evolution operator to a coherent superposition of one-body evolutions in fluctuating one-body fields; the resultant path integral is evaluated stochastically. We first discuss the motivation, formalism, and implementation of su

Harumi Tanigawa

Given a complex structure, we investigate diverging sequences of projective structures on the fixed complex structure in terms of Thurston's parametrization. In particular, we will give a geometric proof to the theorem by Kapovich stating that as the projective structures on a fixed complex structure diverge so do their monodromies. In course of argument

Cumrun Vafa

We construct compact examples of D-manifolds for type IIB strings. The construction has a natural interpretation in terms of compactification of a 12 dimensional `F-theory'. We provide evidence for a more natural reformulation of type IIB theory in terms of F-theory. Compactification of M-theory on a manifold $K$ which admits elliptic fibration is equiva

Matthew J. Strassler

There are many physically interesting superconformal gauge theories in four dimensions. In this talk I discuss a common phenomenon in these theories: the existence of continuous families of infrared fixed points. Well-known examples include finite ${\cal N}=4$ and ${\cal N}=2$ supersymmetric theories; many finite ${\cal N}=1$ examples are known also. These t

Jens Hoppe

M-branes are related to theories on function spaces $\cal{A}$ involving M-linear non-commutative maps from $\cal{A} \times \cdots \times \cal{A}$ to $\cal{A}$. While the Lie-symmetry-algebra of volume preserving diffeomorphisms of $T^M$ cannot be deformed when M>2, the arising M-algebras naturally relate to Nambu's generalisation of Hamiltonian mechanics

D. Han, Y. S. Kim

Lorentz boosts are squeeze transformations. While these transformations are similar to those in squeezed states of light, they are fundamentally different from both physical and mathematical points of view. The difference is illustrated in terms of two coupled harmonic oscillators, and in terms of the covariant harmonic oscillator formalism.

E. V. Gorbar

A method is suggested for the calculation of the DeWitt-Seeley-Gilkey (DWSG) coefficients for the operator $\sqrt{-\nabla^2 + V(x)}$ basing on a generalization of the pseudodifferential operator technique. The lowest DWSG coefficients for the operator $\sqrt{-\nabla^2} + V(x)$ are calculated by using the method proposed. It is shown that the method admits a

J. C. Le Guillou, C. Núñez, F. A. Schaposnik

We consider the fermion-boson mapping in three dimensional space-time, in the Abelian case, from the current algebra point of view. We show that in a path-integral framework one can derive a general bosonization recipe leading, in the bosonic language, to the correct equal-time current commutators of the original free fermionic theory.

Diana Vaman, Mihai Visinescu

The generalized Killing equations for the configuration space of spinning particles (spinning space) are analysed. Simple solutions of the homogeneous part of these equations are expressed in terms of Killing-Yano tensors. The general results are applied to the case of the four-dimensional euclidean Taub-NUT manifold.

H. R. Christiansen, L. N. Epele, H. Fanchiotti, C. A. García Canal

The finite temperature and finite density dependence of the neutron-proton mass difference is analysed in a purely hadronic framework where the $ρ-ω$ mixing is crucial for this isospin symmetry breakdown. The problem is handled within Thermo Field Dynamics. The present results, consistent with partial chiral and charge symmetry restoration, improve the exper

A. D. Jackson, M. K. Şener, J. J. M. Verbaarschot

In this paper we study a random matrix model with the chiral and flavor structure of the QCD Dirac operator and a temperature dependence given by the lowest Matsubara frequency. Using the supersymmetric method for random matrix theory, we obtain an exact, analytic expression for the average spectral density. In the large-n limit, the spectral density can be

J. Kamoshita, Y. Okada, M. Tanaka, I. Watanabe

The physics prospect at future linear $e^+e^-$ colliders for the study of the Higgs triple self-coupling via the process of $e^+e^-$ $\rightarrow Zhh$ is investigated. The measurement of this cross section leads us to the first non-trivial information on the Higgs potential. We found that the Standard Model and the model without the Higgs self-coupling can b

S. V. Goloskokov

The analysis of some effects caused by the spin--dependent pomeron couplings is presented. It is shown that the structure of pomeron--proton and quark--pomeron couplings can be tested in future polarized experiments on elastic $pp$ reactions and diffractive $Q \bar Q$ production.

Jeffrey E. Mandula, Michael C. Ogilvie

In the lattice formulation of the Heavy Quark Effective Theory (LHQET), the classical velocity becomes renormalized. The origin of this renormalization is the reduction of Lorentz (or O(4)) invariance to (hyper)cubic invariance. The renormalization is finite, depends on the form of the discretization of the reduced heavy quark Dirac equation, and can persist

Jarmo Makela

We describe the gravitational degrees of freedom of the Schwarzschild black hole by one free variable. We introduce an equation which we suggest to be the Schroedinger equation of the Schwarzschild black hole corresponding to this model. We solve the Schroedinger equation explicitly and obtain the mass spectrum of the black hole as such as it can be observed

Miroslav Pardy

The string model of gravitational force is proposed where the string forms the mediation of the gravitational interaction between two gravitating bodies. It reproduces the Newtonian results in the first-order approximation and it predicts in the higher-oder approximations the existence of oscillations of the gravitational field between two massive bodies. It

M. C. Leung

Conformal invariants of manifolds of non-positive scalar curvature are studied in association with growth in volume and fundamental group.

Peter B. Thomas, Maya Paczuski

A model for crack propagation and contact line depinning is studied. Although the model contains nonlocal interactions, it obeys general scaling relations for depinning via localized bursts or avalanches. Our numerical result for the roughness exponent in one dimension, $χ=0.49 \pm 0.05$, agrees with recent experiments on cracks measuring the in-plane roughn

Stefan Kehrein, Andreas Mielke

We study the spin--boson model with a sub--Ohmic bath using infinitesimal unitary transformations. Contrary to some results reported in the literature we find a zero temperature transition from an untrapped state for small coupling to a trapped state for strong coupling. We obtain an explicit expression for the renormalized level spacing as a function of the

Yu-Liang Liu

Using the spin-hole coherent state representation and taking a long range antiferromagnetic Nèel order as a background of the localized spin degree part, we have studied the normal state behavior of the t-J model, and shown that a strongly short-range antiferromagnetic correlation of the localized spin degree part is responsible for the anomalous non-Korring

H. W. J. Blöte, J. R. Heringa, A. Hoogland, E. W. Meyer

We review the assumptions on which the Monte Carlo renormalization technique is based, in particular the analyticity of the block spin transformations. On this basis, we select an optimized Kadanoff blocking rule in combination with the simulation of a d=3 Ising model with reduced corrections to scaling. This is achieved by including interactions with second

G. E. Volovik

Glass states formed in the superfluid $^3$He confined in aerogel are discussed. If the short range order corresponds to the A-phase state, the glass state is nonsuperfluid in the long wave length limit. The superfluidity can be restored by application of a small mass current. Transitions between the superfluid and nonsuperfluid glass states can be triggered

C. M. Canali, Chaitali Basu, W. Stephan, V. E. Kravtsov

We compute the distribution function of single-level curvatures, $P(k)$, for a tight binding model with site disorder, on a cubic lattice. In metals $P(k)$ is very close to the predictions of the random-matrix theory (RMT). In insulators $P(k)$ has a logarithmically-normal form. At the Anderson localization-delocalization transition $P(k)$ fits very well the

Nobuo Furukawa

As an effective model to describe perovskite-type manganates (La,$A$)MnO$_3$, the double-exchange model on a cubic lattice is investigated. Spin excitation spectrum of the model in the ground state is studied using the spin wave approximation. Spin wave dispersion relation observed in the inelastic neutron scattering experiment of La$_{0.7}$Pb$_{0.3}$MnO$_3$

Nobuo Furukawa

Magnetic and transport properties of the perovskite-type $3d$ transition-metal oxide (La,Sr)MnO$_3$ are theoretically studied using the double-exchange model in infinite dimension. Magnetoresistance properties as well as the magnetic transition temperatures are in good agreement with the experimental data.

Thomas Gramespacher, Stefan Weigert

Based on the previously proposed notions of action operators and of quantum integrability, frequency operators are introduced in a fully quantum-mechanical setting. They are conceptually useful because a new formulation can be given to unitary perturbation theory. When worked out for quantum spin systems, this variant is found to be formally equivalent to ca

C. Steidel, M. Giavalisco, M. Pettini, M. Dickinson

We report the discovery of a substantial population of star--forming galaxies at $3.0 \simlt z \simlt 3.5$. These galaxies have been selected using color criteria sensitive to the presence of a Lyman continuum break superposed on an otherwise very blue far-UV continuum, and then confirmed with deep spectroscopy on the W. M. Keck telescope. The surface densit

Joao Magueijo, Mike Hobson

We investigate which experiments are better suited to test the robust prediction that cosmic strings do not produce secondary Doppler peaks. We propose a statistic for detecting oscillations in the $C^l$ spectrum, and study its statistical relevance given the truth of an inflationary competitor to cosmic strings. The analysis is performed for single-dish exp

H. C. Spruit

The theory of magnetically accelerated outflows and jets from accretion disks is reviewed at an introductory level, with special attention to problem areas like the launching conditions of the flow at the disk surface, stability of the magnetic field, and collimation mechanisms. This text will appear in R.A.M.J. Wijers, M.B. Davies and C.A. Tout, eds., Physi

Simon D. M. White

The term ``violent relaxation'' was coined by Donald Lynden-Bell as a memorable oxymoron describing how a stellar dynamical system relaxes from a chaotic initial state to a quasi-equilibrium. His analysis showed that this process is rapid, even for systems with many stars, and that it leads to equilibria which may plausibly be related to bounded isot

G. Grinstein, M. A. Muñoz, Yuhai Tu

The phase diagrams and transitions of nonequilibrium systems with multiplicative noise are studied theoretically. We show the existence of both strong and weak-coupling critical behavior, of two distinct active phases, and of a nonzero range of parameter values over which the susceptibility is infinite in any dimension. A scaling theory of the strong-couplin

B. Bakalov, E. Horozov, M. Yakimov

We develop a systematic way for constructing bispectral algebras of commuting ordinary differential operators of any rank $N$. It combines and unifies the ideas of Duistermaat-Grünbaum and Wilson. Our construction is completely algorithmic and enables us to obtain all previously known classes or individual examples of bispectral operators. The method also pr

Alan Weinstein

The aim of this paper is to explain, mostly through examples, what groupoids are and how they describe symmetry. We will begin with elementary examples, with discrete symmetry, and end with examples in the differentiable setting which involve Lie groupoids and their corresponding infinitesimal objects, Lie algebroids.

Michael Christ

A simple geometric condition is sufficient for analytic hypoellipticity of sums of squares of two vector fields in ${\mathbb R}^2$. This condition is proved to be necessary for generic vector fields and for various special cases, and to be both necessary and sufficient for a closely related family of operators.

M. Reuter

The effective average actions for gauge theories and the associated nonperturbative evolution equations which govern their renormalization group flow are reviewed and various applications are described. As an example of a topological field theory, Chern-Simons theory is discussed in detail.

Ashoke Sen

We analyze $M$-theory compactified on $(K3\times S^1)/Z_2$ where the $Z_2$ changes the sign of the three form gauge field, acts on $S^1$ as a parity transformation and on K3 as an involution with eight fixed points preserving SU(2) holonomy. At a generic point in the moduli space the resulting theory has as its low energy limit N=1 supergravity theory in six

Kenneth Lane

Topcolor--assisted technicolor provides a dynamical explanation for electroweak and flavor symmetry breaking and for the large mass of the top quark without unnatural fine tuning. A major challenge is to generate the observed mixing between heavy and light generations while breaking the strong topcolor interactions near~$1\,\tev$. I argue that these phenomen

H. Gargoubi, V. Ovsienko

Let ${\cal D}^k$ be the space of $k$-th order linear differential operators on ${\bf R}$: $A=a_k(x)\frac{d^k}{dx^k}+\cdots+a_0(x)$. We study a natural 1-parameter family of $\Diff(\bf R)$- (and $\Vect(\bf R)$)-modules on ${\cal D}^k$. (To define this family, one considers arguments of differential operators as tensor-densities of degree $λ$.) In this paper w

Alex Kamenev, Yuval Gefen

The small energy anomaly in the single particle density of states of disordered interacting systems is studied for the zero dimensional case. This anomaly interpolates between the non--perturbative Coulomb blockade and the perturbative limit, the latter being an extension of the Altshuler--Aronov zero bias anomaly at d=0. Coupling of the zero dimensional sys

Amitabha Lahiri

A dynamical non-abelian two-form potential gives masses to vector bosons via a topological coupling. Unlike in the abelian case, the two-form cannot be dualized to Goldstone bosons. Duality is restored by coupling a flat connection to the theory in a particular way, and the new action is then dualized to a non-linear sigma model. The presence of the flat con

Manojit Roy, R. E. Amritkar

Chaotic evolution of structures in Coupled map lattice driven by identical noise on each site is studied (a structure is a group of neighbouring lattice-sites for whom values of dynamical variable follow certain predefined pattern). Number of structures is seen to follow a power-law decay with length of the structure for a given noise-strength. An interestin

B. Bakalov, E. Horozov, M. Yakimov

We define Bäcklund--Darboux transformations in Sato's Grassmannian. They can be regarded as Darboux transformations on maximal algebras of commuting ordinary differential operators. We describe the action of these transformations on related objects: wave functions, tau-functions and spectral algebras. This paper is the second of a series of papers (hep-t

B. Bakalov, E. Horozov, M. Yakimov

The present paper establishes a connection between the Lie algebra W_{1+infty} and the bispectral problem. We show that the manifolds of bispectral operators obtained by Darboux transformations on powers of Bessel operators are in one to one correspondence with the manifolds of tau-functions lying in the W_{1+infty}-modules M_beta introduced in our previous

M. Alimohammadi, H. Mohseni Sadjadi

We find the Laughlin states of the electrons on the Poincare half-plane in different representations. In each case we show that there exist a quantum group $su_q(2)$ symmetry such that the Laughlin states are a representation of it. We calculate the corresponding filling factor by using the plasma analogy of the FQHE.

Hitoshi Nishino, S. James Gates,

We demonstrate that in addition to the usual fourth-rank superfield $(W_{a b c d})$ which describes the on-shell theory, a spinor superfield $(J_\a )$ can be introduced into the 11D geometrical tensors with engineering dimensions less or equal to one in such a way to satisfy the Bianchi identities in superspace. The components arising from $J_\a$ are identif

E. Boos, M. Dubinin, L. Dudko

We consider the possibility of Higgs boson detection at LEP II under the resonance threshold ($\sqrt{s}<m_H+m_Z$) in the framework of complete tree level approach to the calculation of the $e^+ e^- \rightarrow ν\bar νb \bar b$ amplitude, simulating b-quark fragmentation to hadrons and taking into account typical detector properties. At the energy below the $

Naoyuki Haba

Though the mass of Higgs particle is the parameter determined by the experiment in the standard model (SM), SUSY models have rather predictive power for the lightest Higgs mass, and its upper bound in some SUSY models are close to the observable region in LEP2. The upper bound of the lightest Higgs mass is analysed systematically on the basis of the $CP$ vio

Benjamin Grinstein, Richard F. Lebed

We present the complete flavor SU(3) decomposition of decay amplitudes for decays of the triplet (B^+_u, B^0_d, B^0_s) of B mesons nonleptonically into two pseudoscalar mesons. This analysis holds for arbitrarily broken SU(3) and can be used to generate amplitude relations when physical arguments permit one to neglect or relate any of the reduced amplitudes.

J. -P. Eckmann, C. -A. Pillet

We generalize earlier studies on the Laplacian for a bounded open domain $Ω\in \real^2$ with connected complement and piecewise smooth boundary. We compare it with the quantum mechanical scattering operator for the exterior of this same domain. Using single layer and double layer potentials we can prove a number of new relations which hold when one chooses {

F. Leyvraz, T. H. Seligman

The concept of structural invariance previously introduced by the authors is used to argue that the connection between random matrix theory and quantum systems with a chaotic classical counterpart is in fact largely exact in the semiclassical limit, holding for all correlation functions and all energy ranges. This goes considerably further than the usual res

Alejandro Gangui, Ruth Durrer, Mairi Sakellariadou

We review recent work aimed at showing how global topological defects influence the shape of the angular power spectrum of the CMB radiation on small scales. While Sachs-Wolfe fluctuations give the dominant contribution on angular scales larger than about a few degrees, on intermediate scales the main rôle is played by coherent oscillations in the baryon rad

Eriko Hironaka

There is a natural stratification of the character variety of a finitely presented group coming from the jumping loci of the first cohomology of one-dimensional representations. Equations defining the jumping loci can be effectively computed using Fox calculus. In this paper, we give an exposition of Fox calculus in the language of group cohomology and in th

Takashi Kimura, Alexander A. Voronov, Gregg J. Zuckerman

We prove that the BRST complex of a topological conformal field theory is a homotopy Gerstenhaber algebra, as conjectured by Lian and Zuckerman in 1992. We also suggest a refinement of the original conjecture for topological vertex operator algebras. We illustrate the usefulness of our main tools, operads and &#34;string vertices&#34; by obtaining new result

Jong-Chan Park, Jeong-Young Ji, Kwang-Sup Soh

We modify the time-dependent electric potential of the Paul trap from a sinusoidal waveform to a square waveform. The exact quantum motion and the Berry&#39;s phase of an electron in the modified Paul trap are found in an analytically closed form. We consider a scheme to detect the Berry&#39;s phase by a Bohm-Aharonov-type interference experiment and point o

Nathan F. Lepora, Adrian Martin

We extend the `topological inflation&#39; of Linde and Vilenkin to {\em unstable} monopoles. This allows the monopole to decay; not inflating eternally, as topological inflation demands. Such a situation happens naturally in some Grand Unified Theories --- such as supersymmetric flipped-$SU(5)$. We analyse analytically the dynamics of inflating monopoles to

John N. Bahcall, Andrew Ulmer

By comparing neutrino fluxes and central temperatures calculated from 1000 detailed numerical solar models, we derive improved scaling laws which show how each of the neutrino fluxes depends upon the central temperature (flux $\propto T^m$); we also estimate uncertainties for the temperature exponents. With the aid of a one-zone model of the sun, we derive e

Spencer Bloch, Hélène Esnault

An analog of Chern-Simons theory is developed in an algebro-geometric setting.

I. Borzsák, H. A. Posch, A. Baranyai

We study the Lyapunov instability of a two-dimensional fluid composed of rigid diatomic molecules, with two interaction sites each, and interacting with a WCA site-site potential. We compute full spectra of Lyapunov exponents for such a molecular system. These exponents characterize the rate at which neighboring trajectories diverge or converge exponentially

Takayuki Nakajima

The most essential problems in Regge calculus discretization are the definitions of the partition function and the integral measure for link--length. In recent work, by considering the one--dimensional case, it was suggested that we should define the partition function in a certain form. But in that work, the model which authors used was over simplified henc

Bai-Ling Wang

We give the definition of the Seiberg-Witten-Floer homology group for a homology 3-sphere. Its Euler characteristic number is a Casson-type invariant. For a four-manifold with boundary a homology sphere, a relative Seiberg-Witten invariant is defined taking values in the Seiberg-Witten-Floer homology group, these relative Seiberg-Witten invariants are applie

Jorma Louko, Stephen N. Winters-Hilt

We consider the Hamiltonian dynamics and thermodynamics of spherically symmetric Einstein-Maxwell spacetimes with a negative cosmological constant. We impose boundary conditions that enforce every classical solution to be an exterior region of a Reissner-Nordström-anti-de Sitter black hole with a nondegenerate Killing horizon, with the spacelike hypersurface

Piotr Kosinski, Pawel Maslanka, Karol Przanowski

The differential calculus on the quantum Heisenberg group is conlinebreak structed. The duality between quantum Heisenberg group and algebra is proved.

Cezary Gonera, Piotr Kosinski, Pawel Maslanka

The differential calculus on n-dimensional quantum Minkowski space covariant with respect to left action of Kappa-Poincar&#39;e group is constructed and its uniqueness is shown.

Stefan Giller, Cezary Gonera, Piotr Kosinski, Pawel Maslanka

The infinitesimal action of Kappa-Poincar&#39;e group on Kappa-Minkowski space is computed both for generators of Kappa-Poincar&#39;e algebra and those of Woronowicz generalized Lie algebra. The notion of invariant operators is introduced and generalized Klein-Gordon equation is written out.

Stefan Giller, Cezary Gonera, Michal Majewski

A nonlinear transformation in the momentum space is constructed which converts the deformed action of Lorentz and Weyl generators on momenta into the standard one.

Piotr Kosinski, Michal Majewski, Pawel Maslanka

The bicovariant differential calculus on the three-dimensional Kappa-Poincar&#39;e group and the corresponding Lie-algebra structure are described. The equivalence of this Lie-algebra structure and the three-dimensional $κ$-Poincaré algebra is proved.

N. A. Gromov

Contractions (and graded contractions) of Lie algebra, Lie bialgebra and Hopf algebra are discussed. It is noticed the fundamental role of E.In{ö}n{ü} and E.P.Wigner idea of degenerate transformations. A constructive algorithm for description of contractions of quantum Cayley-Klein algebras $ so_{z}(n+1; {\bf j}) $ with different choice of the set of primiti

A. Delfino, M. Chiapparini, M. Malheiro, L Belvedere

The equation of state of saturated nuclear matter is derived using two different derivative-coupling Lagrangians. We show that both descriptions are equivalent and can be obtained from the sigma-omega model through an appropriate rescaling of the coupling constants. We introduce generalized forms of this rescaling to study the correlations amongst observable

Arlan Ramsay, Martin E. Walter

This paper gives a first step toward extending the theory of Fourier-Stieltjes algebras from groups to groupoids. If G is a locally compact (second countable) groupoid, we show that B(G), the linear span of the Borel positive definite functions on G, is a Banach algebra when represented as an algebra of completely bounded maps on a C^*-algebra associated wit

Arlan Ramsay

It is proved that every second countable locally Hausdorff and locally compact continuous groupoid has a Borel set of units that meets every orbit and is what is called &#34;lacunary,&#34; a property that implies that the intersection with every orbit is countable.

M. Chaichian, A. P. Demichev

Polynomial relations for generators of $su(2)$ Lie algebra in arbitrary representations are found. They generalize usual relation for Pauli operators in spin 1/2 case and permit to construct modified Holstein-Primakoff transformations in finite dimensional Fock spaces. The connection between $su(2)$ Lie algebra and q-oscillators with a root of unity q-parame

Alex C. Kalloniatis, David G. Robertson

We discuss the bosonized Schwinger model in light-cone quantization, using discretization as an infrared regulator. We consider both the light-cone Coulomb gauge, in which all gauge freedom can be removed and a physical Hilbert space employed, and the light-cone Weyl (temporal) gauge, in which the Hilbert space is unphysical and a Gauss law operator is used

S. M. Bilenky, A. Bottino, C. Giunti, C. W. Kim

We have analyzed the results of the latest terrestrial neutrino oscillation experiments in the framework of a model with mixing of three massive neutrinos and a neutrino mass hierarchy ($ m_1 << m_2 << m_3 $). In this model, oscillations of the terrestrial neutrinos are characterized by three parameters, $ \Delta m^2 = m_3^2 - m_1^2 $ and the squared moduli

G. J. Gounaris, J. Layssac, J. E. Paschalis, F. M. Renard

We report on a set of studies concerning the description of New Physics (NP) effects characterized by a scale much higher than the electroweak scale. We concentrate on the residual effects described by an effective lagrangian involving only bosonic fields and restrict to the case that the Higgs field is described linearly, so that the Higgs particle exists.

J. A. Gracey

The leading order coefficients of the beta-function of QCD are computed in a large N_f expansion. They are in agreement with the three loop MSbar calculation. The method involves computing the anomalous dimension of the operator (G^2_{mu nu})^2 at the d-dimensional fixed point in the non-abelian Thirring model to which QCD is equaivalent in this limit. The e

A. Szczurek, M. Ericson, H. Holtmann, J. Speth

We discuss the present status of the \bar u-\bar d asymmetry in the nucleon and analize the quantities which are best suited to verify the asymmetry. We find that the Drell-Yan asymmetry is the quantity insensitive to the valence quark distributions and very sensitive to the flavour asymmetry of the sea. We compare the prediction of the meson cloud model wit

Joe Sato

We study the possibility of an intermediate scale existing in supersymmetric E$_6$ grand unified theories. The intermediate scale is demanded to be around $10^{12}$ GeV so that neutrinos can obtain masses suitable for explaining the experimental data on the deficit of solar neutrinos with the Mikheev-Smirnov-Wolfenstein solution and the existence of hot dark

John Ellis, Ricardo A. Flores

Supersymmetric model contributions to the neutron electric dipole moment arise via quark electric dipole moment operators, whose matrix elements are usually calculated using the Naive Quark Model (NQM). However, experiments indicate that the NQM does not describe well the quark contributions $Δq$ to the nucleon spin, and so may provide misleading estimates o

P. N. Burrows, H. Masuda, D. Muller, Y. Ohnishi

We have applied so-called `optimised&#39; perturbation theory to resolve the renormalisation-scale (mu) ambiguity of exact O(alpha_s^2) QCD calculations of event shape observables in e+e- --> hadrons. We fitted the optimised predictions for 15 observables to hadronic Z0 decay data from the SLD experiment to determine alpha_s(M_Z^2). Comparing with results us