October 1998 arXiv papers — page 14

J. A. Calzada, M. A. del Olmo, M. A. Rodriguez

Integrable systems in low dimensions, constructed through the symmetry reduction method, are studied using phase portrait and variable separation techniques. In particular, invariant quantities and explicit periodic solutions are determined. Widely applied models in Physics are shown to appear as particular cases of the method.

M. Marinescu, L. You

We propose a physical mechanism for tuning the atom-atom interaction strength at ultra-low temperatures. In the presence of a dc electric field the interatomic potential is changed due to the effective dipole-dipole interaction between the polarized atoms. Detailed multi-channel scattering calculations reveal features never before discussed for ultra-cold at

C. A. A. de Carvalho, R. M. Cavalcanti, E. S. Fraga, S. E. Joras

We derive the semiclassical series for the partition function of a one-dimensional quantum-mechanical system consisting of a particle in a single-well potential. We do this by applying the method of steepest descent to the path-integral representation of the partition function, and we present a systematic procedure to generate the terms of the series using t

John R. Klauder

Coherent states for general systems with discrete spectrum, such as the bound states of the hydrogen atom, are discussed. The states in question satisfy: (1) continuity of labeling, (2) resolution of unity, (3) temporal stability, and (4) an action identity. This set of reasonable physical requirements uniquely specify coherent states for the (bound state po

John R. Klauder

Coherent states can be used for diverse applications in quantum physics including the construction of coherent state path integrals. Most definitions make use of a lattice regularization; however, recent definitions employ a continuous-time regularization that may involve a Wiener measure concentrated on continuous phase space paths. The introduction of cons

Anders Soerensen, Klaus Moelmer

We suggest a method to perform a quantum logic gate between distant qubits by off-resonant field-atom dispersive interactions. The scheme we present is shown to work ideally even in the presence of errors in the photon channels used for communication. The stability against errors arises from the paradoxical situation that the transmitted photons carry no inf

Ortwin Hess, Holger F. Hofmann

We present quantum Maxwell-Bloch equations (QMBE) for spatially inhomogeneous optical semiconductor devices taking into account the quantum noise effects which cause spontaneous emission and amplified spontaneous emission. Analytical expressions derived from the QMBE are presented for the spontaneous emission factor beta and the far field pattern of amplifie

T. Ostoma, M. Trushyk

We provide a derivation of the Einstein Weak Equivalence Principle (WEP) based on our Quantum Field Theory (QFT) of the masseon and graviton particles called ElectroMagnetic Quantum Gravity (EMQG, ref. 1). EMQG provides a framework for understanding Newtonian Inertia as a pure QFT process involving the photon as the vector boson exchange particle. Photons ar

Nimai C. Mukhopadhyay, R. M. Davidson

We discuss the role BLAST can play in the valuable kinematic window of low W and low Q^2.

Denis Lacroix, Philippe Chomaz, Sakir Ayik

The nuclear collective response at finite temperature is investigated for the first time in the quantum framework of the small amplitude limit of the extended TDHF approach, including a non-Markovian collision term. It is shown that the collision width satisfies a secular equation. By employing a Skyrme force, the isoscalar monopole, isovector dipole and iso

W. Wen, P. Chau Huu-Tai, D. Lacroix, Ph. Chomaz

Dynamical symmetry breaking in an expanding nuclear system is investigated in semi-classical and quantum framework by employing a collective transport model which is constructed to mimic the collective behavior of expanding systems. It is shown that the fluctuations in collective coordinates during the expansion are developed mainly by the enhancement of the

Denis Lacroix, Philippe Chomaz

Time-dependent Hartree-Fock simulations of the evolution of excited gold fragments have been performed. The observed dynamics appears more complex than the collective expansion picture. The minimum density is often not reached during the first density oscillation because of the beating of several collective compression modes.

Giovanni Landi, Fedele Lizzi

We present an approximation to topological spaces by {\it noncommutative} lattices. This approximation has a deep physical flavour based on the impossibility to fully localize particles in any position measurement. The original space being approximated is recovered out of a projective limit.

Rich Stankewitz

Let G be a semigroup of rational functions of degree at least two, under composition of functions. Suppose that G contains two polynomials with non-equal Julia sets. We prove that the smallest closed subset of the Riemann sphere which contains at least three points and is completely invariant under each element of G, is the sphere itself.

Rich Stankewitz

We show that the Julia set of a non-elementary rational semigroup G is uniformly perfect when there is a uniform bound on the Lipschitz constants of the generators of G. This also proves that the limit set of a non-elementary Moebius group is uniformly perfect when there is a uniform bound on the Lipschitz constants of the generators of the group and this im

Evgeny Mukhin, Alexander Varchenko

We consider a tensor product of a Verma module and the linear representation of $sl(n+1)$. We prove that the corresponding phase function, which is used in the solutions of the KZ equation with values in the tensor product, has a unique critical point and show that the Hessian of the logarithm of the phase function at this critical point equals the Shapovalo

Martin Bordemann, Martin Walter

Using deformation quantization and suitable 2 by 2 quantum $R$-matrices we show that a list of Toda like classical integrable systems given by Y.B.Suris is quantum integrable in the sense that the classical conserved quantities (which are already in involution with respect to the Poisson bracket) commute with respect to the standard star-product of Weyl type

M. Faber, A. N. Ivanov, A. Mueller, N. I. Troitskaya

Interquark confinement potential is calculated in the dual Monopole Nambu-Jona-Lasinio model with dual Dirac strings as a functional of a dual Dirac string length. The calculation is carried out by the explicit integration over quantum fluctuations of a dual-vector field (monopole-antimonopole collective excitation) around the Abrikosov flux line and string

V. S. Alves, M. Gomes, S. V. L. Pinheiro, A. J. da Silva

In 2+1 dimensions, for low momenta, using dimensional renormalization we study the effect of a Chern-Simons field on the perturbative expansion of fermions self interacting through a Gross Neveu coupling. For the case of just one fermion field, we verify that the dimension of operators of canonical dimension lower than three decreases as a function of the Ch

I. Lovas, K. Sailer, W. Greiner

The Rarita-Schwinger equations are generalised for the delta baryon having spin 3/2 and isospin 3/2. The coupling of the nucleon and the delta fields is studied. A possible generalisation of the Walecka model is proposed.

E. Alvarez, C. Gomez

We prove a c-theorem for holographic theories.

Mikhail Plyushchay

Gogilidze and Surovtsev have claimed recently (hep-th/9809191) that the tachyonic sector can be removed from the spectrum of the relativistic particle with curvature and torsion by a proper gauge choice. We show that the mass-spin dependence obtained by them is incorrect and point out that their gauge surface does not cross all the gauge orbits. We discuss t

Patrick Dorey, Roberto Tateo, Gerard Watts

We make a complete pole analysis of the reflection factors of the boundary scaling Lee-Yang model. In the process we uncover a number of previously unremarked mechanisms for the generation of simple poles in boundary reflection factors, which have implications for attempts to close the boundary bootstrap in more general models. We also explain how different

Yuriko Kato, Shin'ichi Nojiri, Akio Sugamoto

The charged black hole is considered from the viewpoint of D0-brane in the Matrix theory. It can be obtained from the Kaluza-Klein mechanism by boosting the Schwarzschild black hole in a circle, which is the compactified one dimensional space. Especially, how the extremal limit is realized by the Boltzmann gas of D0-brane, has been shown. In the course of ou

Silvio Pallua, Predrag Prester

We derive the operator content of the closed SU(2)_q invariant quantum chain for generic values of the deformation parameter q.

V. Dzhunushaliev, D. Singleton

A recent investigation of the SU(3) Yang-Mills field equations found several classical solutions which exhibited a type of confinement due to gauge fields which increased without bound as $r \to \infty$. This increase of the gauge fields gave these solutions an infinite field energy, raising questions about their physical significance. In this paper we apply

Francesco Antonuccio

A representation of the Lorentz group is given in terms of 4 X 4 matrices defined over a simple non-division algebra. The transformation properties of the corresponding four component spinor are studied, and shown to be equivalent to the transformation properties of the usual complex Dirac spinor. As an application, we show that there exists an algebra of au

A. Niégawa

This paper describes perturbative framework, on the basis of closed-time-path formalism, for studying quasiuniform relativistic quantum field systems near equilibrium and nonequilibrium quasistationary systems. At the first part, starting from first principles, we construct perturbative schemes for relativistic complex-scalar-field theory. We clarify what as

Edward W. Kolb

Two introductory lectures on inflation and dark matter presented at the NATO Advanced Study Institute on Techniques and Concepts of High-Energy Physics.

Edward W. Kolb, Daniel J. H. Chung, Antonio Riotto

There are many reasons to believe the present mass density of the universe is dominated by a weakly interacting massive particle (WIMP), a fossil relic of the early universe. Theoretical ideas and experimental efforts have focused mostly on production and detection of thermal relics, with mass typically in the range a few GeV to a hundred GeV. Here, I will r

H. Navelet, R. Peschanski

We derive the analytic expression of the two one-loop dipole contributions to the elastic 4-gluon amplitude in QCD for arbitrary transverse momentum. The first one corresponds to the double QCD pomeron exchange, the other to an order $α^2$ correction to one-pomeron exchange.

A. G. Grozin

Matching of light-light quark currents in QCD with a heavy flavour and in the low-energy effective QCD is calculated in MSbar at two loops. Heavy-light HQET currents are similarly considered.

Jacek Ciborowski, Jakub Rembielinski

Numerous recent measurements indicate an excess of counts near the endpoint of the electron energy spectrum in tritium decay. We show that this effect is expected if the neutrino is a tachyon. Results of calculations, based on a unitary (causal) theory of tachyons, are presented. The hypothesis of tachyonic neutrinos also offers a natural explanation of the

V. I. Nazaruk

It is shown that there is a double counting in the standard model of $n\bar {n}$ mixing in the medium, resulting in full cancellation of leading terms. The direct calculation of $n\bar{n}$ transition followed by annihilation is performed. The lower limit for the free-space $n\bar{n}$ oscillation time is $τ_{n\bar{n}} \sim T_{n\bar{n}}>10^{16}y$, where $T_{n\

Ehab Malkawi, C. -P. Yuan

We consider a model in which the third family fermions are subjected to an SU(2) interaction different from the first two family fermions. Constrained by the Z-pole data, the heavy gauge boson mass is bounded from below to be about 1.7 TeV at the $2σ$ level. In this model, the flavor mixing between $τ$ and $μ$ can be so large that $Br(τ\to μ\bar{ν_μ} ν_τ)/ B

S. Bronoff, R. Buffa, C. P. Korthals Altes

Thermally reduced QCD leads to three dimensional SU(3) gaugefields coupled to an adjoint scalar field $A_0$. We compute the effective potential in the one-loop approximation and evaluate the VEV's of $TrA_0^2$ and $TrA_0^3$. In the Higgs phase not only the former, but also the latter has a VEV. This happens where the SU(3) gauge symmetry is broken minima

H. Arisue, K. Tabata

We have calculated the large-q expansion for the energy cumulants at the phase transition point in the two-dimensional q-state Potts model to the 23rd order in $1/\sqrt{q}$ using the finite lattice method. The obtained series allow us to give very precise estimates of the cumulants for $q>4$ on the first order transition point. The result confirm us the corr

The CDF Collaboration, F. Abe

If the Technicolor omega_T particle exists, a likely decay mode is omega_T -> gamma pi_T, followed by pi_T -> bb-bar, yielding the signature gamma bb-bar. We have searched 85 pb^-1 of data collected by the CDF experiment at the Fermilab Tevatron for events with a photon and two jets, where one of the jets must contain a secondary vertex implying the presence

P. Abreu

A search for the production of the $η'_c$ meson, the first radial excitation of the ground state of charmonium $η_c$(2980), in the photon-photon fusion reaction at LEP has been performed using the data collected by the DELPHI detector during 1992-1996. No evidence of $η'_c$ production is found in the mass region 3520--3800 MeV/c^2. An upper limit for

G. R. Filewood

The problem of unification of electro-magnetism and gravitation in four dimensions; some new ideas involving torsion. A metric consisting of a combination of symmetric and anti-symmetric parts is postulated and, in the framework of general covariance, used to derive the free-field electro-magnetic stress-energy tensor and the source tensor.

C. C. Briggs

Simple formulas are given for generating Chern-Simons basic invariant polynomials by repeated exterior differentiation for n-dimensional differentiable manifolds having a general linear connection.

Ana Lopez, Eduardo Fradkin

We present an effective theory for the bulk fractional quantum Hall states on the Jain sequences on closed surfaces and show that it has a universal form whose structure does not change from fraction to fraction. The structure of this effective theory follows from the condition of global consistency of the flux attachment transformation on closed surfaces. W

J. L. Cohn

The thermal resistivity of manganites and cuprates is shown to correlate with local lattice distortions and the presence of localized holes as determined from neutron diffraction and nuclear quadrupole resonance. Oxygen doping dependent studies of heat conduction in Y-123 and Hg cuprates suggest that a fraction of the holes in the CuO$_2$ planes are localize

Amelia M. Lapena, Sharon C. Glotzer, Stephen A. Langer, Andrea J. Liu

Partially phase-separated liquid-crystal/polymer dispersions display highly fibrillar domain morphologies that are dramatically different from the typical structures found in isotropic mixtures. To explain this, we numerically explore the coupling between phase ordering and phase separation kinetics in model two-dimensional fluid mixtures phase separating in

Kristian K. Muller-Nedebock, Thomas A. Vilgis

We consider the Langevin dynamics of a semi-dilute system of chains which are random polyampholytes of average monomer charge $q$ and with a fluctuations in this charge of the size $Q^{-1}$ and with freely floating counter-ions in the surrounding. We cast the dynamics into the functional integral formalism and average over the quenched charge distribution in

P. Capuzzi, E. S. Hernandez

We discuss Bose-Einstein condensation in harmonic traps where the confinement has undergone a splitting along one direction. We mostly consider the 3D potentials consisting of two cylindrical wells separated a distance 2a along the z-axis. For ideal gases, the thermodynamics of the confined bosons has been investigated performing exact numerical summations t

O. Benichou, A. M. Cazabat, A. Lemarchand, M. Moreau

We study dynamics of a probe particle, which performs biased diffusive motion in a one-dimensional adsorbed monolayer of mobile hard-core particles undergoing continuous exchanges with a vapor phase. In terms of a mean-field-type approach, based on the decoupling of the third-order correlation functions into a product of the pairwise correlations, we determi

T. Jonsson, K. Jonason, P. Nordblad

The time and temperature dependence of the field-cooled magnetization of a three dimensional Ising spin glass, Fe_{0.5}Mn_{0.5}TiO_{3}, has been investigated. The temperature and cooling rate dependence is found to exhibit memory phenomena that can be related to the memory behavior of the low frequency ac-susceptibility. The results add some further understa

T. H. Oosterkamp, J. W. Janssen, L. P. Kouwenhoven, D. G. Austing

We have measured electron transport through a vertical quantum dot containing a tunable number of electrons between 0 and 40. Over some region in magnetic field the electrons are spin polarized and occupy successive angular momentum states, i.e. the maximum density droplet (MDD) state. The stability region where the MDD state is the ground state, decreases f

Michele Cini, Gianluca Stefanucci, Adalberto Balzarotti

We propose a canonical tranformation approach to the effective interaction $W_{eff}$ between two holes, based on the three-band Hubbard model but ready to include extra interactions as well. An effective two-body Hamiltonian can in principle be obtained including any kind of virtual intermediate states. We derive the closed-form analytic expression of the ef

P. Schuck, X. Viñas

Thomas-Fermi theory for Bose condesates in inhomogeneous traps is revisited. The phase-space distribution function in the Thomas-Fermi limit is $f_0(\bold{R},\bold{p})$ $α$ $δ(μ- H_{cl})$ where $H_{cl}$ is the classical counterpart of the self-consistent Gross-Pitaevskii Hamiltonian. No assumption on the large N-limit is introduced and, e.g the kinetic energ

Itzhack Dana, Mario Feingold, Michael Wilkinson

Band distributions (BDs) are introduced describing quantization in a toral phase space. A BD is the uniform average of an eigenstate phase-space probability distribution over a band of toral boundary conditions. A general explicit expression for the Wigner BD is obtained. It is shown that the Wigner functions for {\em all} of the band eigenstates can be repr

A. M. Selvam, D. Sen, S. M. S. Mody

Continuous periodogram power spectral analysis of daily incidence of acute myocardial infarction (AMI) reported at a leading hospital for cardiology in Pune, India for the two-year period June 1992 to May 1994 show that the power spectra follow the universal and unique inverse power law form of the statistical normal distribution. Inverse power law form for

L. M. Young

We describe the properties and kinematics of the neutral gas in the two dwarf elliptical galaxies NGC 185 and NGC 205, companions of M31. The kinematics of the HI suggest that an internal origin for the gas (i.e. stellar mass loss) should be considered, at least in the case of NGC 185. The molecular clouds in these dwarf ellipticals are similar to Galactic g

Charles D. Dermer, James Chiang

Most models for blazars and gamma-ray bursts involve relativistic plasma outflows powered by accretion processes onto black holes. The blast wave physics developed for cosmological models of GRBs is reviewed. Two points relevant for blazar modeling are made: (1) The injection of nonthermal relativistic particles in the comoving frame is simply treated though

H. Che, Y. Yang, R. J. Nemiroff

Recent optical afterglow observations of gamma-ray bursts indicate a setting and distance scale that many relate to star-formation regions. In this paper, we use $<V/V_{max}>$ and a set of artificial trigger thresholds to probe several potential GRB source density evolutionary scenarios. In particular, we compare a uniform subset of BATSE 4B data to cosmolog

I. Ferreras, L. Cayon, E. Martinez-Gonzalez, N. Benitez

We present a K survey of 29 fields covering approximately 90 arcmin^2 from the Medium Deep Survey (MDS) catalogue down to a completeness magnitude of K=18.0 (limiting magnitude K=19.0). The morphology obtained by the MDS team using high resolution images from HST/WFPC2 along with our NIR observations allow a Colour-Magnitude and Colour-Colour analysis that a

C. Jean, J. Surdej

Light rays from a multiply imaged quasar usually sample different path lengths across the deflector. Extinction in the lensing galaxy may thus lead to a differential obscuration and reddening between the observed macro-lensed QSO images. These effects naturally depend on the precise shape of the extinction law and on the redshift of the lens. By means of num

David Tytler, Scott Burles, Limin Lu, Xiao-Ming Fan

We present constraints on the deuterium to hydrogen ratio (D/H) in the metal-poor gas cloud at redshift $z=0.701$ towards QSO 1718+4807. We use new Keck spectra in addition to Hubble Space Telescope (HST) and International Ultraviolet Explorer (IUE) spectra. We use an improved redshift and a lower \HI column density to model the absorption. The HST spectrum

Tom Abel, Greg L. Bryan, Michael L. Norman

Many questions in physical cosmology regarding the thermal history of the intergalactic medium, chemical enrichment, reionization, etc. are thought to be intimately related to the nature and evolution of pregalactic structure. In particular the efficiency of primordial star formation and the primordial IMF are of special interest. We present results from hig

I. Lehmann, G. Hasinger, A. D. Schwope, Th. Boller

The X-ray luminosity function (XLF) of galaxies is dominated by AGN (classified by their optical spectra) above Lx=10**42 erg/s, below this value by normal galaxies. The X-ray flux of AGN at low X-ray luminosity therefore contains contributions from stellar processes (winds, supernova explosions etc.). Until now it is not clear which fraction of the observed

Arbab I. Arbab

We have examined the cosmological solutions with variable G and $λ$ and bulk viscosity. It is found that these solutions are free from the cosmological problems of the Standard Model. The proposed cosmology consists of two arbitrary parameters which are well constrained. The inflationary solution does not require $Ω=1$ and arises with or without the cosmolog

M. L. McCollough, C. R. Robinson, S. N. Zhang, B. A. Harmon

Using CGRO/BATSE hard X-ray (HXR) data and GHz radio monitoring data from the Green Bank Interferometer (GBI), we have performed a long term study ($\sim$ 1800 days) of the unusual X-ray binary Cyg X-3 resulting in the discovery of a remarkable relationship between these two wavelength bands. We find that, during quiescent radio states, the radio flux is str

H. Di Nella-Courtois, P. Lanoix, G. Paturel

In this paper we present a data analysis regarding globular clusters as possible extragalactic distance indicators. For this purpose, we collected all velocity dispersion measurements published for galactic and M31 globular clusters. The slope and the zero-point of the Faber-Jackson relation were calibrated using Hipparcos distance measurements, and the rela

B. Czerny, A. Schwarzenberg-Czerny, Z. Loska

We derive power density spectra in the optical and X-ray band in the timescale range from several years down to $\sim $ a day. We suggest that the optical power density spectrum consists of two separate components: long timescale variations and short timescale variations, with the dividing timescale around 100 days. The shape of the short timescale component

P. M. Chadwick, K. Lyons, T. J. L. McComb, K. J. Orford

The close X-ray selected BL Lac PKS 2155-304 has been observed using the University of Durham Mark 6 very high energy (VHE) gamma ray telescope during 1996 September/October/November and 1997 October/November. VHE gamma rays with energy > 300 GeV were detected from this object with a time-averaged integral flux of (4.2 +/- 0.7 (stat) +/- 2.0 (sys)) x 10^(-11

Peter Englmaier, Ortwin Gerhard

We present a new model for the gas dynamics in the galactic disk inside the Sun&#39;s orbit. Quasi-equilibrium flow solutions are determined in the gravitational potential of the deprojected COBE NIR bar and disk, complemented by a central cusp and, in some models, an outer halo. These models generically lead to four-armed spiral structure between corotation

Katherine M. Blundell, Steve Rawlings, Chris J. Willott

We present a study of the trends in luminosity, linear size, spectral index, and redshift of classical double radio sources from three complete samples selected at successively fainter low radio-frequency flux-limits. We have been able to decouple the effects of the tight correlation between redshift and luminosity (inherent in any single flux-limited sample

Curtis G. Callan, Alberto Guijosa, Konstantin G. Savvidy

We construct BPS-exact solutions of the worldvolume Born-Infeld plus WZW action of a D5-brane in the background of N D3-branes. The non-trivial background metric and RR five-form field strength play a crucial role in the solution. When a D5-brane is dragged across a stack of N D3-branes a bundle of N fundamental strings joining the two types of branes is cre

P. Zinn-Justin

In this paper, we give an elementary proof of the additivity of the functional inverses of the resolvents of large $N$ random matrices, using recently developed matrix model techniques. This proof also gives a very natural generalization of these formulae to the case of measures with an external field. A similar approach yields a relation of the same type fo

Olaf Lechtenfeld, Alexander Sorin

An infinite class of fermionic flows of the N=(1|1) superconformal Toda lattice hierarchy is constructed and their algebraic structure is studied. We completely solve the semi-infinite N=(1|1) Toda lattice and chain hierarchies and derive their tau functions, which may be relevant for building supersymmetric matrix models. Their bosonic limit is also discuss

W. Berej, P. Rozmej

We point out that harmonic oscillator coherent states, in coordinate representation, require particular phase factor, in order to represent classical time evolution properly. The presence of such a phase is clearly stated only in a minority of scientific sources discussing properties of coherent states.

Dietmar Klemm

We find solutions of the bosonic sector of gauged N=4, D=4 SU(2) $\times$ SU(2) supergravity, which represent dilaton black holes with toroidal or spherical event horizons. The axion is consistently truncated, and the gauge group is broken to U(1) $\times$ U(1). The spherical black holes carry two electric and two magnetic abelian charges, whereas the toroid

R. Walser, J. Williams, J. Cooper, M. Holland

We present a kinetic theory for Bose-Einstein condensation of a weakly interacting atomic gas in a trap. Starting from first principles, we establish a Markovian kinetic description for the evolution towards equilibrium. In particular, we obtain a set of self-consistent master equations for mean fields, normal densities, and anomalous fluctuations. These kin

J. Bezecourt, J. P. Kneib, G. Soucail, T. M. D. Ebbels

We present new observations of the cluster-lens Abell 370: a deep HST/WFPC2 F675W image and ESO 3.6m spectroscopy of faint galaxies. These observations shade new lights on the statistical properties of faint lensed galaxies. In particular, we spectroscopically confirm the multiple image nature of the B2--B3 gravitational pair (Kneib et al. 1993), and determi

Martin Janssen, Rainer Merkt, Andreas Weymer

Networks of random quantum scatterers (S-matrices) form paradigmatic models for the propagation of coherent waves in random S-matrix network models cover universal localization-delocalization properties and have some advantages over more traditional Hamiltonian models. In particular, a straightforward implementation of real space renormalization techniques i

Robin Horan, Martin Lavelle, David McMullan

In this article we investigate charged particles in gauge theories. After reviewing the physical and theoretical problems, a method to construct charged particles is presented. Explicit solutions are found in the Abelian theory and a physical interpretation is given. These solutions and our interpretation of these variables as the true degrees of freedom for

C. Balzereit, Th. Hansmann, T. Mannel, B. Pl&#34;umper

We compute the renormalization of the complete CKM matrix in the MSbar scheme and perform a renormalization group analysis of the CKM parameters. The calculation is simplified by studying only the Higgs sector, which for the β-function of the CKM matrix is at one loop the same as in the full Standard Model. The renormalization group flow including QCD correc

Erasmo Recami

Ettore Majorana, perhaps the greatest Italian theoretical physicist of this century (Enrico Fermi compared him to Galilei and Newton), disappeared misteriously from Naples in 1938, when he was 31. In the first part of this work we outline his scientific personality (on the basis of letters, documents, testimonies collected by us in about twenty years) and th

Fabian Braun, Jan von Delft

We present a truly canonical theory of superconductivity in ultrasmall metallic grains by variationally optimizing fixed-N projected BCS wave-functions, which yields the first full description of the entire crossover from the bulk BCS regime (mean level spacing $d \ll$ bulk gap $\tildeΔ$) to the ``fluctuation-dominated&#39;&#39; few-electron regime ($d\gg\ti

F. Sattin, L. Salasnich

The scattering among three particles interacting through $1/r^2$ forces, with opposite charges and widely different masses, is studied in a coplanar geometry. The present work shows that at low impact velocities the output of the collision presents typical fingerprints of chaos. The details of the process are investigated.

Pontus Svenson, Mats G. Nordahl

Using T=0 Monte Carlo simulation, we study the relaxation of graph coloring (K-COL) and satisfiability (K-SAT), two hard problems that have recently been shown to possess a phase transition in solvability as a parameter is varied. A change from exponentially fast to power law relaxation, and a transition to freezing behavior are found. These changes take pla

A. Betsch, R. Bilger, W. Brodowski, H. Calen

Differential cross sections of the reactions $pp \to d\pi^+$ and $pp \to pn\pi^+$ have been measured at $T_p = 400$ MeV by detecting the charged ejectiles in the angular range $4^0 \leq \Theta_{Lab} \leq 21^\circ$. The deduced total cross sections agree well with those published previously for neighbouring energies. The invariant mass spectra are observed to

Mark D. Roberts

Phrase structure trees have a hierarchical structure. In many subjects, most notably in Taxonomy such tree structures have been studied using ultrametrics. Here syntactical hierarchical phrase trees are subject to a similar analysis, which is much siompler as the branching structure is more readily discernible and switched. The occurence of hierarchical stru

Neil F. Johnson, Pak Ming Hui, Rob Jonson, Ting Shek Lo

An evolving population, in which individual members (`agents&#39;) adapt their behaviour according to past experience, is of central importance to many disciplines. Because of their limited knowledge and capabilities, agents are forced to make decisions based on inductive, rather than deductive, thinking. We show that a population of competing agents with si

T. Asaka, M. Kawasaki, Masahide Yamaguchi

We investigate cosmological moduli problem in the gauge-mediated supersymmetry breaking (GMSB). A mini-inflation (oscillating inflation) takes place when a scalar field corresponding to the flat direction in GMSB oscillates along the logarithmic potential induced by the gauge-mediation mechanism. It is shown that this oscillating inflation can sufficiently d

Dae-Yup Song

A generalization of driven harmonic oscillator with time-dependent mass and frequency, by adding total time-derivative terms to the Lagrangian, is considered. The generalization which gives a general quadratic Hamiltonian system does not change the classical equation of motion. Based on the observation by Feynman and Hibbs, the propagators (kernels) of the s

Mark D. Roberts

The relative motion of many particles can be described by the geodesic deviation equation. This can be derived from the second covariant variation of the point particle&#39;s action. It is shown that the second covariant variation of the string action leads to a string deviation equation.

Feng Yuan, Kuang-Ta Chao

We present a calculation of diffractive charm jet production at hadron colliders in perturbative QCD based on the two-gluon exchange model. Differing from the previous calculations, we abandon the use of the effective color-singlet vitual gluon simplification, and use the real gluon in the calculations for the partonic process. We find the final result is fr

Daniel Enstrom

A scenario is presented where large quark-gluon plasma (QGP) objects escaping the quark-hadron transition in the early Universe account for the baryonic dark matter as well as act as the sources for gamma-ray bursts. Two basic assumptions are made. Firstly, we assume that a QGP consisting of u,d and s quarks is the absolute ground state of QCD and secondly,

Michael Small, Kevin Judd

Fourier spectral estimates and, to a lesser extent, the autocorrelation function are the primary tools to detect periodicities in experimental data in the physical and biological sciences. We propose a new method which is more reliable than traditional techniques, and is able to make clear identification of periodic behavior when traditional techniques do no

Marin Soljacic, Suzanne Sears, Mordechai Segev

We show that an azimuthally-periodically-modulated bright ring &#34;necklace&#34; beam can self-trap in self-focusing Kerr media and can exhibit stable propagation for very large distances. These are the first bright (2+1) D beams to exhibit stable self-trapping in a system described by the cubic (2+1) D Nonlinear Schrodinger Equation (NLSE).

L. Kaplan, N. T. Maitra, E. J. Heller

We consider quantum mechanics on constrained surfaces which have non-Euclidean metrics and variable Gaussian curvature. The old controversy about the ambiguities involving terms in the Hamiltonian of order hbar^2 multiplying the Gaussian curvature is addressed. We set out to clarify the matter by considering constraints to be the limits of large restoring fo

Dik Bouwmeester, Jian-Wei Pan, Matthew Daniell, Harald Weinfurter

We present the experimental observation of polarization entanglement for three spatially separated photons. Such states of more than two entangled particles, known as GHZ states, play a crucial role in fundamental tests of quantum mechanics versus local realism and in many quantum information and quantum computation schemes. Our experimental arrangement is s

F. Cannata, M. Ioffe, G. Junker, D. Nishnianidze

General first- and higher-order intertwining relations between non-stationary one-dimensional Schrödinger operators are introduced. For the first-order case it is shown that the intertwining relations imply some hidden symmetry which in turn results in a $R$-separation of variables. The Fokker-Planck and diffusion equation are briefly considered. Second-orde

C. J. Isham, J. Butterfield

The Kochen-Specker theorem asserts the impossibility of assigning values to quantum quantities in a way that preserves functional relations between them. We construct a new type of valuation which is defined on all operators, and which respects an appropriate version of the functional composition principle. The truth-values assigned to propositions are (i) c

M. D. Todorov

The classical Helmholtz problem is applied for modelling the axisymmetric inviscid cusp-ended separated flow around a sphere. Two coordinate systems are employed: polar for initial calculations and parabolic the latter being more suitable for investigation of infinitely-long stagnation zones. Scaled coordinates are introduced and difference schemes for the f

V. G. Anfinogentov, A. E. Hramov

The paper consider a complex dynamics of electron beam with virtual cathode and local neutralization of the beam charge density near anode. Different types of nonlinear behaviour, including deterministic chaos, were treated. It is shown that chaotic dynamics arises as results of spatiotemporal structures interaction.

Nimai C. Mukhopadhyay

We limit ourselves basically to the SU(2) flavor sector of the CKM matrix, as probed in processes like nuclear $β$-decay, normal and radiative muon capture and neutrino reactions. Current interests in this primarily stem from our aspirations to interpret the weak form factors of the nucleon in the framework of QCD. Given a standard set of known form factors,

R. M. Davidson, Nimai C. Mukhopadhyay, M. S. Pierce, R. A. Arndt

We investigate the model dependence and the importance of choice of database in extracting the {\it physical} nucleon-Delta(1232) electromagnetic transition amplitudes, of interest to QCD and baryon structure, from the pion photoproduction observables. The model dependence is found to be much smaller than the range of values obtained when different datasets