September 2003 arXiv papers — page 11

Michael J. West, Patrick Cote, Henry C. Ferguson, Michael D. Gregg

We confirm and extend our previous detection of a population of intergalactic globular clusters in Abell 1185, and report the first discovery of an intergalactic globular cluster in the nearby Virgo cluster of galaxies. The numbers, colors and luminosities of these objects can place constraints on their origin, which in turn may yield new insights to the evo

Ion V. Vancea

The relation between coordinates and the solutions of the stationary Schrodinger equation in the noncommutative algebra of functions on $R^{2N}$ is discussed. We derive this relation for a certain class of wave functions for which the quantum prepotentials depend linearly on the coordinates similarly to the commutative case. Also, the differential equation s

Roberto Longo, Feng Xu

Let A be a local conformal net of factors on the circle with the split property. We provide a topological construction of soliton representations of the tensor product of n copies of A, that restrict to true representations of subnet inviant under cyclic permutations (cyclic orbifold). We prove a quantum index theorem for our sectors relating the Jones index

Noam Erez, Yakir Aharonov, Benni Reznik, Lev Vaidman

In order to reduce errors, error correction codes (ECCs) need to be implemented fast. They can correct the errors corresponding to the first few orders in the Taylor expansion of the Hamiltonian of the interaction with the environment. If implemented fast enough, the zeroth order error predominates and the dominant effect is of error prevention by measuremen

P. L. Krapivsky, S. Redner, J. Tailleur

We investigate the evolution of a single unbounded interface between ordered phases in two-dimensional Ising ferromagnets that are endowed with single-spin-flip zero-temperature Glauber dynamics. We examine specifically the cases where the interface initially has either one or two corners. In both examples, the interface evolves to a limiting self-similar fo

Troy C. Andre, Jonathan L. Rosner

Isosinglet vector-like quarks are predicted by some unified theories of electroweak and strong interactions. We study hadron collider signatures for the production and decay of isosinglet vector-like quarks with charge -1/3. Previous analyses of Run I data from the Fermilab Tevatron are used to set lower limits of 100--200 GeV/c^2 on the mass of such quarks,

Pavel Kroupa

The stellar IMF has been found to be an invariant Salpeter power-law (alpha=2.35) above about 1 Msun, but at the same time a massive star typically has more than one companion. This constrains the possible formation scenarios of massive stars, but also implies that the true, binary-star corrected stellar IMF could be significantly steeper than Salpeter, alph

Frank E. Close, Philip R. Page

Tests are discussed to distinguish c cbar, hybrid charmonium and molecular interpretations of the narrow Belle resonance at 3872 MeV.

Sharada Iyer Dutta, Sasa Ratkovic, Madappa Prakash

Explicit expressions for the differential and total rates and emissivities of neutrino pairs from the photo-neutrino process $e^\pm + γ\to e^\pm + ν+ \barν$ in hot and dense matter are derived. Full information about the emitted neutrinos is retained by evaluating the squared matrix elements for this process which was hitherto bypassed through the use of Len

C. Martin Gaskell, Rene W. Goosmann, Robert R. J. Antonucci, David H. Whysong

We present extinction curves derived from the broad emission lines and continua of large samples of both radio-loud and radio-quiet AGNs. The curves are significantly flatter in the UV than are curves for the local ISM. The reddening curves for the radio-quiet LBQS quasars are slightly steeper than those of the radio-loud quasars in the UV, probably because

Elias Katsoulis, David Kribs

In this paper we verify that the graph forms a complete invariant for Banach algebra isomorphisms of tensor algebras of graphs. For tensor algebras associated with countable directed graphs having no sinks the graph forms an invariant for algebraic isomorphisms as well. The graph also forms a complete invariant for w*-bicontinuous isomorphisms of free semigr

Stephan J. Huber, Qaisar Shafi

We show how the seesaw mechanism for neutrino masses can be realized within a five dimensional (5D) warped geometry framework. Intermediate scale standard model (SM) singlet neutrino masses, needed to explain the atmospheric and solar neutrino oscillations, are shown to be proportional to M_Pl\exp((2c-1)πkR), where c denotes the coefficient of the 5D Dirac m

T. Prokopec, R. P. Woodard

We compute the one loop self energy, in a locally de Sitter background, for a massless fermion which is Yukawa-coupled to a massless, minimally coupled scalar. We then solve the modified Dirac equation resulting from inclusion of the self energy. We find faster-than-exponential growth in the fermion wave function, consistent with the production of fermions t

W. J. B. Corradi, G. A. P. Franco, J. Knude

The results of a spectroscopic programme aiming to investigate the kinematics of the local interstellar medium components towards the Southern Coalsack and Chamaeleon-Musca dark clouds are presented. The analysis is based upon high-resolution (R ~ 60,000) spectra of the insterstellar NaI D absorption lines towards 63 B-type stars (d < 500 pc) selected to cov

Andrei Okounkov, Nikolai Reshetikhin, Cumrun Vafa

We propose a new duality involving topological strings in the limit of large string coupling constant. The dual is described in terms of a classical statistical mechanical model of crystal melting, where the temperature is inverse of the string coupling constant. The crystal is a discretization of the toric base of the Calabi-Yau with lattice length $g_s$. A

Jose M. Soler

A functional $E_{xc}[ρ(\r,ε)]$ is presented, in which the exchange and correlation energy of an electron gas depends on the local density of occupied states. A simple local parametrization scheme is proposed, entirely from first principles, based on the decomposition of the exchange-correlation hole in scattering states of different relative energies. In its

A. Le Fevre, M. Ploszajczak, V. D. Toneev, G. Auger

We study the anisotropy effects measured with INDRA at GSI in central collisions of Xe+Sn at 50 A.MeV and Au+Au at 60, 80, 100 A.MeV incident energy. The microcanonical multifragmentation model with non-spherical sources is used to simulate an incomplete shape relaxation of the multifragmenting system. This model is employed to interpret observed anisotropic

Ph. Podsiadlowski, N. Langer, A. J. T. Poelarends, S. Rappaport

We systematically examine how the presence in a binary affects the final core structure of a massive star and its consequences for the subsequent supernova explosion. Interactions with a companion star may change the final rate of rotation, the size of the helium core, the strength of carbon burning and the final iron core mass. Stars with initial masses lar

M. Dominik

Among all galactic microlensing events, those involving a passage of the observed source star over the caustic created by a binary lens are particularly useful in providing information about stellar atmospheres, the dynamics of stellar populations in our own and neighbouring galaxies, and the statistical properties of stellar and sub-stellar binaries. This p

Léonie Canet, Bertrand Delamotte, Olivier Deloubrière, Nicolas Wschebor

We investigate non-equilibrium critical phenomena using a nonperturbative renormalization group method. Reaction-diffusion processes are described by a scale dependent effective action which evolution is governed by very generic flow equations, that are derived. They allow to recover the critical exponents of directed percolation, and moreover to calculate t

Benedicte Ponsot

Liouville field theory on the pseudosphere is considered (Dirichlet conditions). We compute explicitely the bulk-boundary structure constant with two different methods: first we use a suggestion made by Hosomichi in JHEP 0111 (2001) that relates this quantity directly to the bulk-boundary structure constant with Neumann conditions, then we do a direct comput

Yasha Shnir

This paper is concerned with magnetic monopole solutions of SU(3) Yang-Mills-Higgs system beyond the Bogomol&#39;nyi-Prasad-Sommerfield limit. The different SU(2) embeddings, which correspond to the fundamental monopoles, as well the embedding along composite root are studied. The interaction of two different fundamental monopoles is considered. Dissolution

W. Rodejohann

We propose a flexible and model independent parametrization of the neutrino mixing matrix, which takes advantage of the fact that there are up to three small quantities in neutrino mixing phenomenology: (i) the deviation from maximal mixing of solar neutrinos, (ii) the mixing matrix element U_{e3} and (iii) the deviation from maximal mixing of atmospheric ne

Amina Helmi

It has been recently claimed that the confined structure of the debris from the Sagittarius dwarf implies that the dark-matter halo of our Galaxy should be nearly spherical, in strong contrast with predictions from cold dark-matter (CDM) simulations, where dark halos are found to have typical density axis ratios of 0.6 - 0.8. In this letter, numerical simula

I. Eremin, O. Kamaev, M. V. Eremin

Starting from the three-band $p-d$ Hubbard Hamiltonian we derive an effective $t-J$ model including electron-phonon interaction of quasiparticles with optical phonons. Within the effective Hamiltonian we analyze the influence of electronic correlations and electron-phonon interaction on the dynamical spin susceptibility in layered cuprates. We find a huge is

Jiri Tolar, Petr Hajicek

A measurement has been proposed by B. d&#39;Espagnat that would distinguish from one another some ensembles that are differently prepared but correspond to the same density matrix. Here, the idea is modified so that it becomes applicable to much more general situations. The method is illustrated in simple examples. Some matter of concern might then be that i

Alessandro Bacchetta, Andreas Schaefer, Jian-Jun Yang

We perform a calculation of the Sivers function in a spectator model of the nucleon, with scalar and axial-vector diquarks. We make use of gluon rescattering to produce the nontrivial phases necessary to generate the Sivers function. The inclusion of axial-vector diquarks enables us to obtain a nonzero Sivers function for down quarks. Using the results of ou

Matteo D&#39;Astuto, Alessandro Mirone, Paola Giura, Dorothee Colson

We investigate the low energy acoustical and optical modes in $\mathrm{HgBa_2CuO_{4+δ}}$ using inelastic x-ray scattering (IXS). The experimental phonon dispersion and the dynamical structure factor are compared with an atomic shell model, and the set of the atomic potentials obtained are discussed. Our results are also compared with those obtained by Raman

Klaus Hamacher

A summary of QCD results obtained at e+e- experiments in recent years is given. Emphasis is put on basic QCD tests and α_s measurements with event shapes.

Kacper Zalewski

Four experimental results, which seem to contradict the established ideas about the Bose-Einstein correlations in multiple particle production processes, are briefly presented and dicussed.

Kjell Rosquist

An explicit fluid flow simulation of electromagnetic wave propagation in the gravitational field of a Schwarzschild black hole is given. The fluid has a constant refractive index and a spherically symmetric inward directed flow. The resulting form of the metric leads to a new coordinate system in which the Schwarzschild vacuum is written in Gordon&#39;s form

Branko Dragovich, Zoran Rakic

Extension of Feynman&#39;s path integral to quantum mechanics of noncommuting spatial coordinates is considered. The corresponding formalism for noncommutative classical dynamics related to quadratic Lagrangians (Hamiltonians) is formulated. Our approach is based on the fact that a quantum-mechanical system with a noncommutative configuration space may be re

Wlodzimierz Godlowski, Marek Szydlowski, Adam Krawiec

We discuss some observational constraints resulting only from SNIa observations, imposed on the behavior of the original flat Cardassian model, and its extension with the curvature term included. We test the models using the Perlmutter SN Ia data as well as the new Knop and Tonry samples. We estimate the Cardassian model parameters using the best-fitting pro

Azwinndini Muronga

The transport coefficient of shear viscosity is studied for a hadron matter through microscopic transport model, the Ultra--relativistic Quantum Molecular Dynamics (UrQMD), using the Green--Kubo formulas. Molecular--dynamical simulations are performed for a system of light mesons in a box with periodic boundary conditions. Starting from an initial state comp

Azwinndini Muronga

Non-equilibrium fluid dynamics derived from the extended irreversible thermodynamics of the causal Müller--Israel--Stewart theory of dissipative processes in relativistic fluids based on Grad&#39;s moment method is applied to the study of the dynamics of hot matter produced in ultra--relativistic heavy ion collisions. The temperature, energy density and entr

Sever Silvestru Dragomir

The main aim of this monograph is to survey some recent results obtained by the author related to reverses of the Schwarz, triangle and Bessel inequalities. Some Gruss&#39; type inequalities for orthonormal families of vectors in real or complex inner product spaces are presented as well. Generalizations of the Boas-Bellman, Bombieri, Selberg, Heilbronn and

Somdatta Bhattacharya, Shibaji Roy

By directly solving the equations of motion we obtain the time dependent solutions of supergravities with dilaton and a $q$-form field-strength in arbitrary dimensions. The metrics are assumed to have the symmetries ISO($p+1$) $\times$ SO($d-p-2,1$) and can be regarded as those of the magnetically charged Euclidean or space-like branes. When we impose the ex

Igor Rodnianski, Terence Tao

We show that in dimensions $n \geq 6$ that one has global regularity for the Maxwell-Klein-Gordon equations in the Coulomb gauge provided that the critical Sobolev norm $\dot H^{n/2-1} \times \dot H^{n/2-2}$ of the initial data is sufficiently small. These results are analogous to those recently obtained for the high-dimensional wave map equation but unlike

P. A. Mazzali, J. Deng, N. Tominaga, K. Maeda

The spectra of SN 2003dh, identified in the afterglow of GRB030329, are modeled using radiation transport codes. It is shown that SN 2003dh had a high explosion kinetic energy ($\sim 4 \times 10^{52}$ erg in spherical symmetry), making it one of the most powerful hypernovae observed so far, and supporting the case for association between hypernovae and Gamma

J. Q. You, Y. Nakamura, Franco Nori

A central problem for implementing efficient quantum computing is how to realize fast operations (both one- and two-bit ones). However, this is difficult to achieve for a collection of qubits, especially for those separated far away, because the interbit coupling is usually much weaker than the intrabit coupling. Here we present an experimentally feasible me

Jack Laiho

Results at NLO in (PQ)ChPT for extracting $ε^\prime/ε$ from lattice data are discussed.

G. M. D&#39;Ariano, P. Perinotti, M. F. Sacchi

The expectation value <O> of an arbitrary operator O can be obtained via a universal measuring apparatus that is independent of O, by changing only the data-processing of the outcomes. Such a ``universal detector&#39;&#39; performs a joint measurement on the system and on a suitable ancilla prepared in a fixed state, and is equivalent to a positive operator

Marco Genovese

In this proceeding I review the main experimental results obtained at IENGF (Turin, Italy) by using a source of entangled photons realised superposing, by means of an optical condenser, type I PDC produced in two crystals. More in details, after having described how this source is built, I will report on a Bell inequalities test obtained with it. Then I desc

Robert Carroll

This is a mainly expository sketch showing how some integrable systems (e.g. KP or KdV) can be viewed as quantum mechanical in nature.

J. Formanek, R. J. Lombard, J. Mares

We study wave equations with energy dependent potentials. Simple analytical models are found useful to illustrate difficulties encountered with the calculation and interpretation of observables. A formal analysis shows under which conditions such equations can be handled as evolution equation of quantum theory with an energy dependent potential. Once these c

Prashant K. Purohit, Jane&#39; Kondev, Rob Phillips

Biophysicists and structural biologists increasingly acknowledge the role played by the mechanical properties of macromolecules as a critical element in many biological processes. This change has been brought about, in part, by the advent of single molecule biophysics techniques that have made it possible to exert piconewton forces on key macromolecules and

Shaun N. Mosley

The electromagnetic field can be expressed in terms of two complex potentials $ α, β,$ which are related to the Debye potentials. The evolution equations for these potentials are derived, which are separable either in parabolic coordinates (leading to the radiation fields) or in radial coordinates (multipole fields). Potentials corresponding to focused wave

A. Loinger

The electric charge of the quantization condition of Dirac&#39;s monopole may have any value, we are not obliged to identify it with the electron charge. Consequently the magnetic charge of the monopole is quite arbitrary: Dirac&#39;s monopole is a mere object of science fiction.

H. Hammer, B. Lionheart

We explain the main concepts centered around Sharafutdinov&#39;s ray transform, its kernel, and the extent to which it can be inverted. It is shown how the ray transform emerges naturally in any attempt to reconstruct optical and stress tensors within a photoelastic medium from measurements on the state of polarization of light beams passing through the stra

H. S. Karayan, Sh. J. Martirosyan

Some information and logical properties of multistable semi-conductor plazma are discussed and the concept of physical logic system Lp on their basis is entered. Lp contains exclusively values of some quantitative characteristic physical size of plazma and transformation of a set of such sizes by means of plazma-field interaction. The opportunity nonmathemat

Alberto De Gregorio

At the &#34;Domus Galilaeana&#34; in Pisa, many original documents and records are kept, which belong to the scientific activity carried out by Enrico Fermi until 1938. I compared those documentary sources with the supported evidences, the personal recollections, concerning the discovery that hydrogenated substances increase the radioactivity induced by neut

Suckjoon Jun, John Bechhoefer

Loop formation in long molecules occurs many places in nature, from solutions of carbon nanotubes to polymers inside a cell. In this article, we review theoretical studies of the static and dynamic properties of polymer loops. For example, long polymers must search many configurations to find a &#34;target&#34; binding site, while short polymers are stiff an

A. A. Raduta, L. Zamick, E. Moya de Guerra, Amand Faessler

The excitation energies of single analog states in even-odd Ti isotopes and double analog states in even-even Ti isotopes are microscopically described in a single j-shell formalism. A projection procedure for generalized BCS states has been used. As an alternative description a particle-core formalism is presented. The latter picture provides a two-paramete

Andrzej Deloff

The recent high statistics measurement of the pp -> pp eta reaction at an excess energy Q=15.5 MeV has been analysed by means of partial wave decomposition of the cross section. Guided by the dominance of the final state 1S0 pp interaction (FSI), we keep only terms involving the FSI enhancement factor. The measured p-p and p-eta effective mass spectra can be

T. Falter, W. Cassing, K. Gallmeister, U. Mosel

We investigate meson electroproduction off complex nuclei in the kinematic regime of the HERMES experiment using a semi-classical transport model which is based on the Boltzmann-Uehling-Uhlenbeck (BUU) equation. We discuss coherence length and color transparency effects in exclusive rho^0 production as well as hadron formation and attenuation of charged pion

Eric Braaten, H. -W. Hammer

We conjecture that QCD can be tuned to an infrared limit cycle in the three-nucleon system by adjusting the up and down quark masses to critical values at which the binding energies of the deuteron and its spin-singlet partner are tuned to zero. At the critical point, the triton would have infinitely many arbitrarily-shallow excited states with the ratio of

Pavel Winternitz

In this series of lectures presented at the CIMPA Winter School on Discrete Integrable Systems in Pondicherry, India, in February, 2003 we give a review of the application of Lie point symmetries, and their generalizations to the study of difference equations. The overall theme of these lectures could be called &#34;continuous symmetries of discrete equation

Elena V. Kazantseva, Andrei I. Maimistov, Jean-Guy Caputo

The propagation of extremely short pulses of electromagnetic field (electromagnetic spikes) is considered in the framework of a model where the material medium is represented by anharmonic oscillators with cubic nonlinearities (Duffing model) and waves can propagate only in the right direction. The system of reduced Maxwell-Duffing equations admits two famil

P. Gralewicz

The connection between symmetries and linearizations of discrete-time dynamical systems is being inverstigated. It is shown, that existence of semigroup structures related to the vector field and having linear representations enables reduction of linearization problem to a system of first order partial differential equations. By means of inverse of the Poinc

G. B. Mainland

The difficulties that typically prevent numerical solutions from being obtained to finite-energy, two-body, bound-state Bethe-Salpeter equations can often be overcome by expanding solutions in terms of basis functions that obey the boundary conditions. The method discussed here for solving the Bethe-Salpeter equation requires only that the equation can be Wi

David W. Kribs

We present a generalization of bilateral weighted shift operators for the noncommutative multivariable setting. We discover a notion of periodicity for these shifts, which has an appealing diagramatic interpretation in terms of an infinite tree structure associated with the underlying Hilbert space. These shifts arise naturally through weighted versions of c

Marco Fontana, Salah Kabbaj

This note investigates two long-standing conjectures on the Krull dimension of integer-valued polynomial rings and of polynomial rings, respectively, in the context of (locally) essential domains.

Domokos Szász, Tamás Varjú

For Young systems, i.e. for hyperbolic systems without/with singularities satisfying Lai-Sang Young&#39;s axioms (which imply exponential decay of correlation and the CLT) a local CLT is proven. In fact, a unified version of the local CLT is found, covering among others the absolutely contionuous and the arithmetic cases. For the planar Lorentz process with

Hjalmar Rosengren, Michael Schlosser

Using Krattenthaler&#39;s operator method, we give a new proof of Warnaar&#39;s recent elliptic extension of Krattenthaler&#39;s matrix inversion. Further, using a theta function identity closely related to Warnaar&#39;s inversion, we derive summation and transformation formulas for elliptic hypergeometric series of Karlsson-Minton-type. A special case yield

Domokos Szász, Tamás Varjú

The aim of this survey is twofold. First we show how the Markov tower construction is applicable for obtaining finer stochastic properties, like a local limit theorem of probability theory. Here the fundamental method is the study of the spectrum of the Fourier transform of the Perron--Frobenius operator. These ideas and results are applicable to all systems

Michel Benaim, Olivier Raimond

Let $M$ be a compact Riemannian manifold. A {\em self-interacting diffusion} on $M$ is a stochastic process solution to $$dX_t = dW_t(X_t) - \frac{1}{t}(\int_0^t \nabla V_{X_s}(X_t)ds)dt$$ where $\{W_t\}$ is a Brownian vector field on $M$ and $V_x(y) = V(x,y)$ a smooth function. Let $μ_t = \frac{1}{t} \int_0^t δ_{X_s} ds$ denote the normalized occupation mea

Noureddine El Karoui

Let X be a n*p matrix and l_1 the largest eigenvalue of the covariance matrix X^{*}*X. The &#34;null case&#34; where X_{i,j} are independent Normal(0,1) is of particular interest for principal component analysis. For this model, when n, p tend to infinity and n/p tends to gamma in (0,\infty), it was shown in Johnstone (2001) that l_1, properly centered and s

Gottfried Barthel, Jean-Paul Brasselet, Karl-Heinz Fieseler, Ludger Kaup

The proof of the combinatorial Hard Lefschetz Theorem for the ``virtual&#39;&#39; intersection cohomology of a not necessarily rational polytopal fan that has been presented by K. Karu completely establishes Stanley&#39;s conjectures for the generalized $h$-vector of an arbitrary polytope. The main ingredients, namely, Poincare Duality and the Hard Lefschetz

Toshiyuki Tanisaki

Theory of the quantized flag manifold as a quasi-scheme (non-commutative scheme) has been developed by Lunts-Rosenberg. They have formulated an analogue of the Beilinson-Bernstein correspondence using the $q$-differential operators introduced in their earlier paper. In this paper we shall establish its modified version using a class of $q$-differential opera

G. J. Chaitin

The simultaneous appearance in May 2003 of four books on the Riemann hypothesis (RH) provoked these reflections. We briefly discuss whether the RH should be added as a new axiom, or whether a proof of the RH might involve the notion of randomness.

Florian Breuer

Let E be a modular elliptic curve defined over a rational function field k of odd characteristic. We construct a sequence of Heegner points on E, defined over a $Z_p^{\infty}$-tower of finite extensions of k, and show that these Heegner points generate a group of infinite rank. This is a function field analogue of a result of C.Cornut and V.Vatsal

Hiroshi Yamauchi

In this article, we study module categries of simple current extensions of vertex operator algebras. Under certain assumptions, we show that every module for a rational vertex operator algebra be lifted to a twisted module for an extended algebra with an abelian symmetry.

V. P. Nair, S. Randjbar-Daemi

We analyze the Landau problem and quantum Hall effect on $S^3$ taking a constant background field proportional to the spin connection on $S^3$. The effective strength of the field can be tuned by changing the dimension of the representation to which the fermions belong. The effective action for the edge excitations of a quantum Hall droplet in the limit of a

Patrick Dorey, Clare Dunning, Roberto Tateo

We review the proof of a conjecture concerning the reality of the spectra of certain PT-symmetric quantum mechanical systems, obtained via a connection between the theories of ordinary differential equations and integrable models. Spectral equivalences inspired by the correspondence are also discussed.

Galliano Valent

The multi-centre metrics are a family of euclidean solutions of the empty space Einstein equations with self-dual curvature. For this full class, we determine which metrics do exhibit an extra conserved quantity quadratic in the momenta, induced by a Killing-St\&#34; ackel tensor. Our systematic approach brings to light a subclass of metrics which correspond

Bikash Chandra Paul

The chaotic inflationary model of the early universe, proposed by Linde is explored in the brane world considering matter described by a minimally coupled self interacting scalar field. We obtain cosmological solutions which admit evolution of a universe either from a singularity or without a singularity. It is found that a very weakly coupled self-interacti

Manoelito M. de Souza

Discrete interaction models for the classical harmonic oscillator are used for introducing new mathematical generalizations in the usual continuous formalism. The inverted harmonic potential and generalized discrete hyperbolic and trigonometric functions are defined.

M. A. Braun, B. Vlahovic

Charm photoproduction rates off nuclei below the nucleon threshold are estimated using the phenomenologically known structure functions both for x>1 and x<1. The rates rapidly fall below the threshold from values of the order 10 pb for Pb close to the threshold (at 7.5 GeV) down to values of the order 1 pb at 6 GeV.

Ulf-G. Meißner

In the first part of the talk, I review what we know (or rather do not know) about the structure of the QCD vacuum in the presence of strange quarks. Chiral perturbation theory allows to study reactions of pions and kaons and to further sharpen our understanding of symmetry violation in QCD. I review recent progress on the description of pion-kaon scattering

Bernard Silvestre-Brac, Claude Semay, Ilya M. Narodetskii, A. I. Veselov

We discuss the validity of replacing the complicated three-body confinement operator of the Y string junction type by three kinds of approximation which are numerically much simpler to handle: a one-body operator with the junction point at the centre of mass, a two-body operator corresponding to half the perimeter of the triangle formed by the three particle

Saul Barshay, Georg Kreyerhoff

The likelihood of a sizable, direct CP-violating asymmetry in the decays $B^\mp\to K^\mpη$, is calculated within the framework of the model which originally predicted a sizeable asymmetry in $π^\mpη(η&#39;)$. It is shown in a transparent manner that these decays are the best places for providing the first clear evidence for direct CP violation in the decays

S. F. King, I. N. R. Peddie

We show how two different family symmetries can be used to address the flavour problem in SO(10)-like models. The first is based on a gauged $U(1)_F$, whose problems dissappear in the context of a type I string model embedding. The second is based on $SU(3)_F$, the maximal family group consistent with SO(10); in this case the family symmetry is more constain

Prashanth Jaikumar, Anupam Mazumdar

We consider the possibility of regarding the maximum temperature $\tm$ of a plasma of inflaton decay products as a Hagedorn temperature connected with the transition from an inflaton-dominated epoch to a radiation-dominated universe. Employing a ``bottom-up&#39;&#39; approach to inflaton decay, we show that the limiting temperature $T_{\rm H}\sim m_ϕ$, as ob

V. Gimenez, L. Giusti, S. Guerriero, V. Lubicz

We present an exploratory study of a gauge-invariant non-perturbative renormalization technique. The renormalization conditions are imposed on correlation functions of composite operators in coordinate space on the lattice. Numerical results for bilinears obtained with overlap and O(a)-improved Wilson fermions are presented. The measurement of the quark cond

M. Hasenbusch, K. Jansen, D. Pleiter, H. St&#34;uben

We define a benchmark suite for lattice QCD and report on benchmark results from several computer platforms. The platforms considered are apeNEXT, CRAY T3E, Hitachi SR8000, IBM p690, PC-Clusters, and QCDOC.

David H. Adams

We determine the free field hypercubic Dirac operator which is optimally close to satisfying the Ginsparg-Wilson relation. Inserting this operator into the overlap formula, we show that the analytic locality bound on the resulting overlap Dirac operator is substantially stronger than in the standard case. This improvement generally persists in gauge backgrou

Michele Caselle, Martin Hasenbusch, Marco Panero

The effective string picture of confinement is used to derive theoretical predictions for the interquark potential at finite temperature. At short distances, the leading string correction to the linear confining potential between a heavy quark-antiquark pair is the &#34;Lüscher term&#39;&#39;. We assume a Nambu--Goto effective string action, and work out sub

Slavo Kratochvila, Philippe de Forcrand

While the grand canonical partition function Z_{GC}(mu) with chemical potential mu explicitly breaks the Z_3 symmetry with the Dirac determinant, the canonical partition function at fixed baryon number Z_C(B) is manifestly Z_3-symmetric. We compare Z_{GC}(mu=0) and Z_C(B=0) formally and by numerical simulations, in particular with respect to properties of th

Luigi Del Debbio, Claudio Pica

The chiral symmetry at finite lattice spacing of Ginsparg-Wilson fermionic actions constrains the renormalization of the lattice operators; in particular, the topological susceptibility does not require any renormalization, when using a fermionic estimator to define the topological charge. Therefore, the overlap formalism appears as an appealing candidate to

Y. Nakamura, V. Bornyakov, M. N. Chernodub, Y. Koma

We present results for QCD with $N_f=2$ flavors of dynamical quarks using nonperturbatively improved Wilson fermions at finite temperature on $16^3 \times 8$ and $24^3 \times 10$ lattices. We determine the transition temperature in the range of quark masses $0.6 \lesssim m_π/m_ρ\leq 0.8$. After fixing the Maximal Abelian gauge we investigate the contribution

M. Imachi, Y. Shinno, H. Yoneyama

In Monte Carlo simulation, lattice field theory with a $θ$ term suffers from the sign problem. This problem can be circumvented by Fourier-transforming the topological charge distribution $P(Q)$. Although this strategy works well for small lattice volume, effect of errors of $P(Q)$ becomes serious with increasing volume and prevents one from studying the pha

Kei-Ichi Kondo

We discuss the possible form of gluon and ghost propagators in the infrared region of Yang-Mills theory in the covariant gauge from the viewpoint of general principles of quantized gauge field theories.

CP-PACS, JLQCD Collaboration, :, K-I. Ishikawa

The non-perturbative $\csw$ determined by the Schrödinger functional (SF) method with the RG-improved gauge action in dynamical $N_f=3$ QCD shows a finite volume effect when the numerical simulations are carried out at a constant lattice size $L/a$. We remove the unwanted finite volume effect by keeping physical lattice extent $L$ at a constant. The details

C. Driouichi

The CP asymmetry predicted by the Standard Model in the decay modes Bs;d -> J/psi eta and Bs -> J/psi phi is very small, and the observation of a sizeable e ect would be a clear indication of new physics beyond the Standard Model. Contrary to the final state J/psi phi, the former final state is a CP eigenstate, and therefore complex angular distribution anal

Elisabetta Barberio

Studying the properties of the W boson plays a key role in precision tests of the Standard Model. The key measurements performed over the last decade will be reviewed. W-pair and single-W cross-sections and W decay branching fractions are determined and agree well with theoretical predictions. Including the analysis of differential distributions, trilinear a

K. Arms

Using a 13.7 fb-1 data sample collected with the CLEO II and II.V detectors, we report new branching fraction measurements for two Cabibbo-suppressed decay modes of the D+ meson: BR(D+ -> pi+ pi0) = (1.31 +/- 0.17 +/- 0.09 +/- 0.09) x 10^(-3)and BR(D+ -> K+ K0bar) = (5.24 +/- 0.43 +/- 0.20 +/- 0.34) x 10^(-3) which are significant improvements over past meas

J. M. Butterworth

I give an outline and some discussion of the results presented during the hadronic final states parallel sessions of the meeting, and some opinions about the current state of play and future directions in this area.

Hasko Stenzel

A combination of measurements of alpha_s in e+e- annihilation at LEP is presented. Distributions of various event-shape variables measured by ALEPH, DELPHI, L3 and OPAL at centre-of-mass energies from 41 GeV to 206 GeV are analysed in a common theoretical framework using O(a_s**2)+NLLA predictions. The dominant theoretical uncertainties associated to missing

Gaurav Khanna

We extend the treatment of the problem of the gravitational waves produced by a particle of negligible mass orbiting a Kerr black hole using black hole perturbation theory in the time domain, to elliptic and inclined orbits. We model the particle by smearing the singularities in the source term using narrow Gaussian distributions. We compare results (energy

Lorenzo Iorio

In this paper we examine the possibility of testing the equivalence principle, in its weak form, by analyzing the orbital motion of a pair of artificial satellites of different composition moving along orbits of identical shape and size in the gravitational field of Earth. It turns out that the obtainable level of accuracy is, realistically, of the order of