December 1998 arXiv papers — page 12

A. Smailagic, E. Spallucci

In this letter we implement a recently proposed {\it spacetime duality} approach to dualize a two dimensional, Abelian, gauge field theory, which has no dual version under $p$--duality. Our result suggests that spacetime duality spans a new, wider, class of dual theories, which cannot be related one to another by $p$--duality transformations.

R. Gaida, V. Tretyak, Yu. Yaremko

Collective center-of-mass variables are introduced in the Lagrangian formalism of the relativistic classical mechanics of directly interacting particles. It is shown that the transition to the Hamiltonian formalism leads to the Bakamjian-Thomas model. The quantum-mechanical system consisting of two spinless particles is investigated. Quasi-relativistic corre

M. Pillin

In a recent paper it was shown that the response of an integrable QFT under variation of the Unruh temperature can be computed from a S-matrix preserving deformation of the form factor approach. We give explicit expressions for the deformed two-particle formfactors for various integrable models: The Sine-Gordon and SU(2) Thirring model, several perturbed min

A. Dobado, J. R. Pelaez

We present a brief pedagogical introduction to the Effective Electroweak Chiral Lagrangians, which provide a model independent description of the WW interactions in the strong regime. When it is complemented with some unitarization or a dispersive approach, this formalism allows the study of the general strong scenario expected at the LHC, including resonanc

A. Ringwald, F. Schrempp

We review our ongoing theoretical and phenomenological study of the discovery potential for instanton-induced events in deep-inelastic scattering (DIS) at HERA. Constraints from recent lattice simulations will be exploited and translated into a ``fiducial'' kinematical region for our predictions of the instanton-induced DIS cross-section.

V. V. Kiselev

The characteristic scale of neutral current, provided by an extension of Standard Model with a local group over the right-handed fermions, determines the smallness of neutrino masses of Dirac kind. The experimental observation of neutrino oscillations imposes the stringent limit on the $Z^\prime$ physics appearance at low energies.

G. M. Shore

Contents: 1. Introduction; 2. The First Moment Sum Rule for $g_1^p$; 3. The Parton Model and the `Proton Spin'; 4. The CPV Method and Topological Charge Screening; 5. Experiment; 6. Semi-Inclusive Polarised DIS.

G. M. Shore

Many of the distinctive and subtle features of the dynamics in the $U_A(1)$ channel in QCD can be related to gluon topology, more precisely to the topological susceptibility $χ(k^2) = i\int d^4x~e^{ikx}< 0|T~Q(x)~Q(0)|0>$, where $Q = {\a_s\over8π} {\rm tr} G_{\m\n} \tilde G^{\m\n}$ is the gluon topological charge density. The link is the $U_A(1)$ axial (ABJ)

F. Benatti, R. Floreanini

We present some general considerations on possible experimental tests of Bell&#39;s locality in the neutral kaon system, and comment on the recent literature on the topic.

E. Levin, A. D. Martin, M. G. Ryskin

We summarize the discussions on the value of the survival probabilities of large rapidity gap (LRG) processes at Durham WS&#39;98.

Gabriela Barenboim, Florian Scheck

We argue that regardless of the outcome of future Long Baseline experiments, additional information will be needed to unambiguously decide among the different scenarios of neutrino mixing. We use, for this purpose, a simple test of underground data: an asymmetry between downward and upward going events. Such an asymmetry, in which matter effects can be cruci

V. A. Miransky

The dynamics with an infrared stable fixed point in the conformal window in QCD like theories (with a relatively large number of fermion flavors) is studied. The dependence of masses of colorless bound states on a bare fermion mass is described. In particular it is shown that in such dynamics, glueballs are much lighter than bound states composed of fermions

Aksel Hiorth Orsland, H. Hogaasen

We discuss a model for heavy mesons where the light quark (u or d) moves in the colour electric field from a heavy quark (c or b) placed in the center of the bag. We calculate energy spectra for pionic and photonic transitions from excited states. The transition amplitudes and the branching ratios between electromagnetic and pionic transitions compares favor

Xiao-Gang He, Guey-Lin Lin

We study $B \to η&#39; X_s$ within the framework of the Standard Model. Several mechanisms such as $b \to η&#39; s g$ from the QCD anomaly, and $b \to η&#39;s $ and $B\to η&#39; s \bar q$ from four-quark operators are treated simultaneously. We find that the first mechanism give a significant contribution to the branching ratio for $B\to η&#39; X_s$, while t

Xiao-Gang He

In this talk I discuss two topics related to B decays. I will first discuss the Standard Model prediction for $B\to η&#39; X_s$, and then discuss how to use experimental information from $B\to J/ψK^*$ to test CP violation beyond the SM.

Ping Chen, Norman Christ, Geoerge Fleming, Adrian Kaehler

A serious difficulty in conventional lattice field theory calculations is the coupling between the chiral and continuum limits. With both staggered and Wilson fermions, the chiral limit cannot be realized without first taking the limit of vanishing lattice spacing. In this talk, we report on extensive studies of the domain wall formulation of lattice fermion

The OPAL Collaboration, G. Abbiendi et al

The branching ratio for the decay tau->e nue nutau has been measured using Z0 decay data collected by the OPAL experiment at LEP. In total 33073 tau->e nue nutau candidates were identified from a sample of 186197 selected tau decays, giving a branching ratio of 17.81 +- 0.09(stat) +_ 0.06(sys)%. This result is combined with other measurements to test e-mu an

Ph. Droz-Vincent

Klein-Gordon equation with minimal coupling in FRW-like spacetimes with compact but not necessarily isotropic neither homogeneous space sections. Beside exceptional cases, the kernel is invariant under continuous isometries.

M. Heller, W Sasin

We briefly review some results concerning the problem of classical singularities in general relativity, obtained with the help of the theory of differential spaces. In this theory one studies a given space in terms of functional algebras defined on it. Then we present a generalization of this method consisting in changing from functional (commutative) algebr

H. C. Rosu

I employ heuristically the strictly isospectral double Darboux method based on the general superpotential of unbroken nonrelativistic supersymmetry suggesting a few small steps of principle for extending its range of applications toward relativistic (gauge) physics. The application of the method to minisuperspace quantum cosmology is also briefly presented

Steve Hitchcock, Les Carr, Wendy Hall

As most electronic journals available today have been derived from print originals, print journals have become a vital element in the broad development of electronic journals publishing. Further dependence on the print publishing model, however, will be a constraint on the continuing development of e-journals, and a series of conflicts are likely to arise. M

Martin Zapotocky, Paul M. Goldbart

The scattering of light at large wave-vector magnitudes k in nematic systems containing topological defects is investigated theoretically. At large k the structure factor S(k) is dominated by power-law contributions originating from singular order-parameter variations associated with topological defects and from transverse thermal fluctuations of the nematic

Anand Bhattacharya, Igor Zutic, Oriol T. Valls, Allen M. Goldman

The angular dependence of the nonlinear transverse magnetic moment of untwinned high-quality single crystals of optimally doped YBCO have been studied at a temperature of 2.5K using a low frequency AC technique. The absence of any signature at angular period 2π/4is analyzed in light of the numerical predictions of such a signal for a pure d-wave order parame

M. Bockrath, D. H. Cobden, J. Lu, A. G. Rinzler

An interacting one-dimensional (1D) electron system is predicted to behave very differently than its higher-dimensional counterparts. Coulomb interactions strongly modify the properties away from those of a Fermi liquid, resulting in a Luttinger liquid (LL) characterized by a power-law vanishing of the density of states at the Fermi level. Experiments on one

Robert E. Rudd, Jeremy Q. Broughton

We present simulations of the dynamic and temperature dependent behavior of Micro-Electro-Mechanical Systems (MEMS) by utilizing recently developed parallel codes which enable a coupling of length scales. The novel techniques used in this simulation accurately model the behavior of the mechanical components of MEMS down to the atomic scale. We study the vibr

Sharon C. Glotzer, Claudio Donati

We examine the phenomenon of dynamical heterogeneity in computer simulations of an equilibrium, glass-forming liquid. We describe several approaches to quantify the spatial correlation of single-particle motion, and show that spatial correlations of particle displacements become increasingly long-range as the temperature decreases toward the mode coupling cr

G. Parisi, M. Picco, F. Ritort

We investigate the phase transition in a strongly disordered short-range three-spin interaction model characterized by the absence of time reversal symmetry in the Hamiltonian. In the mean-field limit the model is well described by the Adam-Gibbs-DiMarzio scenario for the glass transition; however in the short-range case this picture turns out to be modified

Patrick A. Lee

It has become clear in the past several years that the cuprates show many unusual properties, both in the normal and superconducting states, especially in the underdoped region. In particular, gap-like behavior is observed in magnetic properties, c-axis conductivity and photoemission, whereas in-plane transport properties are only slightly affected by the ps

P. A. Mello, H. U. Baranger

We develop a statistical theory describing quantum-mechanical scattering of a particle by a cavity when the geometry is such that the classical dynamics is chaotic. This picture is relevant to a variety of systems, ranging from atomic nuclei to microwave cavities; the main application here is to electronic transport through ballistic microstructures. The the

Arne Brataas, Yu. V. Nazarov, J. Inoue, G. E. W. Bauer

We study transport in ferromagnetic single-electron transistors. The non- equilibrium spin accumulation on the island caused by a finite current through the system is described by a generalized theory of the Coulomb blockade. It enhances the tunnel magnetoresistance and has a drastic effect on the time- dependent transport properties. A transient decay of th

D. V. Shantsev, M. R. Koblischka, Y. M. Galperin, T. H. Johansen

Exact analytical results are obtained for the magnetization of a superconducting thin strip with a general behavior J_c(B) of the critical current density. We show that within the critical-state model the magnetization as function of applied field, B_a, has an extremum located exactly at B_a=0. This result is in excellent agreement with presented experimenta

A. Diaz-Guilera, C. J. Perez-Vicente, A. Arenas

We study the dynamical behavior of an ensemble of oscillators interacting through short range bidirectional pulses. The geometry is 1D with periodic boundary conditions. Our interest is twofold. To explore the conditions required to reach fully synchronization and to invewstigate the time needed to get such state. We present both theoretical and numerical re

Bastien Chopard, Pascal Luthi, Stefan Marconi

We show that the lattice Boltzmann formalism can be used to describe wave propagation in a heterogeneous media, as well as solid-body-like systems and fracture propagation. Several fundamental properties of real fractures (such as propagation speed and transition between rough and smooth crack surfaces) are well captured by our approach.

S. Sergeenkov, H. Bougrine, M. Ausloos, A. Gilabert

The magneto-thermoelectric power (TEP) $ΔS(T,H)$ of perovskite type manganise oxide $La_{0.6}Y_{0.1}Ca_{0.3}MnO_3$ is found to exhibit a sharp peak at some temperature $T^{*}=170K$. By approximating the true shape of the measured magneto-TEP in the vicinity of $T^{*}$ by a linear triangle of the form $ΔS(T,H)\simeq S_p(H)\pm B^{\pm}(H)(T^{*}-T)$, we observe

Jean-Louis Barrat, Lydéric Bocquet

It is well known that, at a macroscopic level, the boundary condition for a viscous fluid at a solid wall is one of &#34;no-slip&#34;. The liquid velocity field vanishes at a fixed solid boundary. In this paper, we consider the special case of a liquid that partially wets the solid, i.e. a drop of liquid in equilibrium with its vapor on the solid substrate h

M. O. Oktel, L. S. Levitov

Optical excitations in a Bose gas are demonstrated to be very sensitive to many-body effects. At low temperature the momentum relaxation is provided by momentum exchange collisions, rather than by elastic collisions. A collective excitation mode forms, which in a Boltzmann gas is manifest in a collision shift and dramatic narrowing of spectral lines. In the

Joerg C. Lemm

A new general framework is presented for implementing complex a priori knowledge, having in mind especially situations where the number of available training data is small compared to the complexity of the learning task. A priori information is hereby decomposed into simple components represented by quadratic building blocks (quadratic concepts) which are th

Benny Davidovich, H. G. E. Hentschel, Zeev Olami, Itamar Procaccia

The creation of fractal clusters by diffusion limited aggregation (DLA) is studied by using iterated stochastic conformal maps following the method proposed recently by Hastings and Levitov. The object of interest is the function $Φ^{(n)}$ which conformally maps the exterior of the unit circle to the exterior of an $n$-particle DLA. The map $Φ^{(n)}$ is obta

Dipak Munshi, Adrian L. Melott, Peter Coles

The cumulant correlators, $C_{pq}$, are statistical quantities that generalise the better-known $S_p$ parameters; the former are obtained from the two-point probability distribution function of the density fluctuations while the latter describe only the one-point distribution. If galaxy clustering develops from Gaussian initial fluctuations and a small-angle

Marc Gagne, Jeff A. Valenti, Jeffrey L. Linsky, Gianpiero Tagliaferri

We present Extreme Ultraviolet Explorer spectroscopy and photometry of the nearby F8 V star HD 35850 (HR 1817). The EUVE spectra reveal 28 emission lines from Fe IX and Fe XV to Fe XXIV. The Fe XXI 102, 129 A ratio yields an upper limit for the coronal electron density, log n < 11.6 per cc. The EUVE SW spectrum shows a small but clearly detectable continuum.

S. Ragland, A. Richichi

A lunar occultation event of the Wolf-Rayet star WR 112 (type WC9) has been observed simultaneously from two independent telescopes at lambda = 2.2microns, allowing us to investigate this source with an angular resolution of approx 0.003 arc-seconds. We have detected a circumstellar dust envelope whose brightness distribution can be approximately fitted by a

F. Caputo, S. Cassisi, M. Castellani, G. Marconi

We present a detailed study of the color magnitude diagram (CMD) of the dwarf spheroidal galaxy Leo I, based on archival Hubble Space Telescope data. Our photometric analysis, confirming previous results on the brighter portion of the CMD, allow us to obtain an accurate sampling of the stellar populations also at the faint magnitudes corresponding to the Mai

D. Michael Crenshaw, Steven B. Kraemer, Albert Boggess, Stephen P. Maran

We present a study of the intrinsic absorption lines in the ultraviolet spectra of Seyfert 1 galaxies. We find that the fraction of Seyfert 1 galaxies that show absorption associated with their active nuclei is more than one-half (10/17), which is much higher than previous estimates (3 - 10%) . There is a one-to-one correspondence between Seyferts that show

Witold Maciejewski, Donald P. Cox

We propose simple, explicit, analytical approximations for the kinematics of an adiabatic blast wave propagating in an exponentially stratified ambient medium, and for the onset of radiative cooling, which ends the adiabatic era. Our method, based on the Kompaneets implicit solution and the Kahn approximation for the radiative cooling coefficient, gives stra

Noam Soker, Geoffrey C. Clayton

We examine the structure of cool magnetic spots in the photospheres of evolved stars, specifically asymptotic giant branch (AGB) stars and R Coronae Borealis stars. We find that the photosphere of a cool magnetic spot will be above the surrounding photosphere of AGB stars, opposite to the situation in the sun. This results from the behavior of the opacity, w

J. Kwiecinski, A. D. Martin, A. Stasto

We calculate the cross sections for neutrino interactions with (isoscalar) nuclear targets in the energy domain all the way up to 10^12 GeV. Small x QCD effects are included by using a unified BFKL/DGLAP formalism which embodies non-leading log(1/x) contributions. The few free parameters which specify the input parton distributions are determined by fitting

Chris Done, Piotr Zycki

We present the first significant detection of relativistic smearing of the X-ray reflection spectrum from the putative accretion disk in the low/hard state of Cyg X-1. The ionization state, and amount of relativistic smearing are simultaneously constrained by the X-ray spectra, and we conclude that the disk is not strongly ionized, does not generally extend

A. W. Strong, I. V. Moskalenko

We are constructing a model which aims to reproduce observational data of many kinds related to cosmic-ray origin and propagation: direct measurements of nuclei, antiprotons, electrons and positrons, gamma-rays, and synchrotron radiation. These data provide many independent constraints on any model. Propagation of primary and secondary nucleons, primary and

J. Heidt

Since the last meeting on BL Lac objects 10 years ago, BL Lac host galaxies and their cluster environment have gained much attention. Hence, our current knowledge of the properties of BL Lac host galaxies and their cluster environment has improved considerably, which will be reviewed. The importance of future observing programs using (very) large telescopes

Luiz da Costa

This year marks the 20th anniversary of the effective beginning of large, systematic redshift surveys of galaxies. These surveys have had a major impact on observational cosmology and on our current understanding of large-scale structures in the Universe. To celebrate this remarkable period some landmark observational results are reviewed and our current und

Jihn E. Kim

I review the axion physics with emphases on the couplings of the very light axion and a possible realization in superstring models.

C. Gruppioni, P. Ciliegi, M. Rowan-Robinson, L. Cram

A deep survey of the European Large Area ISO Survey (ELAIS) field in the southern celestial hemisphere (hereinafter S1) has been carried out with the Australia Telescope Compact Array (ATCA) at 1.4 GHz. The S1 region, covering about 4 square degrees, has been also surveyed in the mid- and far-infrared (5-200 micron) with the Infrared Space Observatory (ISO).

C. Charbonnel, S. Vauclair

Why is the lithium abundance constant in the so-called lithium plateau while all predictions suggest that it should vary from star to star? Can we find a &#34;lithium attractor&#34; which would remain stable in halo stars while fundamental parameters (M_*, Teff, [Fe/H]) vary?

L. Lara, I. Marquez, W. D. Cotton, L. Feretti

In the frame of the study of a new sample of large angular size radio galaxies selected from the NRAO VLA Sky Survey, we have made radio observations of J2114+820, a low power radio galaxy with an angular size of 6&#39;. Its radio structure basically consists of a prominent core, a jet directed in north-west direction and two extended S-shaped lobes. We have

Bruce Grossan, Earl Spillar, Robert Tripp, Norbert Pirzkal

IR and Radio band observations of heavily extinguished regions in starburst galaxies suggest a very high SN rate associated with such regions. Optically measured supernova (SN) rates may therefore underestimate the total SN rate by factors of up to 10, due to the high extinction to SNe in starburst regions. The IR/radio SN rates come from a variety of indire

Jorgen Ellegaard Andersen, Gregor Masbaum

The moduli space $M$ of semi-stable rank 2 bundles with trivial determinant over a complex curve carries involutions naturally associated to 2-torsion points on the Jacobian of the curve. For every lift of a 2-torsion point to a 4-torsion point, we define a lift of the involution to the determinant line bundle $Ł$. We obtain an explicit presentation of the g

Alekhin Sergey, Kataev Andrei

We performed the detailed NLO analysis of the combined CCFR $xF_3$ and $F_2$ structure functions data and extracted the value of $α_s$, parameters of distributions and higher-twist (HT) terms using the direct solution of the DGLAP equation. The value of $α_s(M_Z)=0.1222\pm 0.0048 (exp)\pm 0.0040(theor)$ was obtained. The result has larger central value and e

I. V. Gaidaenko, A. V. Novikov, V. A. Novikov, A. N. Rozanov

Enhanced radiative corrections generated in SUSY extensions of the Standard Model make the fit of the precision data ($Z$-boson decay parameters and $W$-boson mass) worse. This negative effect is washed out for heavy enough squarks due to decoupling property of SUSY models. We find that even for light squarks the enhanced radiative corrections can be small.

Noriko Akutsu, Yasuhiro Akutsu

We study a two-dimensional honeycomb lattice gas model with both nearest- and next-nearest-neighbor interactions in a staggered field, which describes the surface of stoichiometrically binary crystal. We calculate anisotropic step tension, step stiffness, and equilibrium island shape, by an extended random walk method. We apply the results to Si(111) 7$\time

William L. Clarke

Micron sized, neutral, non-dielectric particles immersed in a viscous fluid can be trapped in the focal plane of a Gaussian beam. A particle can absorb energy from such a beam with a large radial intensity gradient, resulting in substantial temperature gradients and a radiometric torque which causes it to spin rapidly about an axis perpendicular to the flux

Jakob Yngvason

The paper reviews rigorous results about quantum dots, in particular exact solutions for few electron dots and limit theorems for high magnetic fields and/or high electron number.

Alan T. Huckleberry, Stefan Kebekus, Thomas Peternell

It is proved that if S^6 possesses an integrable complex structure, then there exists a 1-dimensional family of pairwise different exotic complex structures on P_3(C). This follows immediately from the main result of the paper: S^6 is not the underlying differentiable manifold of an almost homogeneous complex manifold X. Via elementary Lie theoretic techniqu

Igor Bandos, Jerzy Lukierski

We consider the superparticle models invariant under the supersymmetries with tensorial central charges, which were not included in D=4 Haag-Lopuszanski-Sohnius (HLS) supersymmetry scheme. We present firstly a generalization of D=4 Ferber-Shirafuji (FS) model with fundamental bosonic spinors and tensorial central charge coordinates. The model contains four f

Andrea Cavagna

By means of extensive numerical simulations we show that all the distinctive features of the minority game introduced by Challet and Zhang (1997), are completely independent from the memory of the agents. The only crucial requirement is that all the individuals must posses the same information, irrespective of the fact that this information is true or false.

Andrei Mourachkine

The complete scenario of high-Tc superconductivity based on experimental data from electron-tunneling spectroscopy on underdoped, overdoped and Ni-doped Bi2212 single crystals using a break-junction technique is presented. There are two different types of superconductivity in cuprates: superconductivity due to pairing of spinons on charged stripes and magnet

T. Aittokallio, M. Gyllenberg, J. Hietarinta, T. Kuusela

We introduce a graphical presentation for the false nearest neighbors (FNN) method. In the original method only the percentage of false neighbors is computed without regard to the distribution of neighboring points in the time-delay coordinates. With this new presentation it is much easier to distinguish deterministic chaos from noise. The graphical approach

S. H. Rhie, A. C. Becker, D. P. Bennett, P. C. Fragile

We present the observations of the binary lensing event MACHO-98-SMC-1 conducted at the Mt.~Stromlo 74&#34; telescope by the Microlensing Planet Search (MPS) collaboration. The MPS data constrain the first caustic crossing to have occurred after 1998 June 5.55 UT and thus directly rule out one of the two fits presented by the PLANET collaboration (model II).

V. Celebonovic

Preliminary results of a theoretical determination of the basic parameters of the internal structure of the five Uranian satellies are presented.

J. Einasto, M. Einasto, E. Tago, A. A. Starobinsky

Observed power spectrum of matter found in Papers I and II is compared with analytical power spectra. Spatially flat cold and mixed dark matter models with cosmological constant and open models are considered. The primordial power spectrum of matter is determined using the power spectrum of matter and the transfer functions of analytical models. The primordi

J. Einasto, M. Einasto, E. Tago, V. M&#34;uller

A new method to determine the bias parameter of galaxies relative to matter is suggested. The method is based on the assumption that gravity is the dominating force which determines the formation of the structure in the Universe. Due to gravitational instability the galaxy formation is a threshold process: in low-density environments galaxies do not form and

J. Einasto, M. Einasto, E. Tago, A. A. Starobinsky

We calculate the mean power spectrum of galaxies using published power spectra of galaxies and clusters of galaxies. On small scales we use the power spectrum derived from the 2-dimensional distribution of APM galaxies, on large scales we use power spectra derived from 3-dimensional data for galaxy and cluster samples. Spectra are reduced to real space and t

Ernest Ma

Assuming the canonical seesaw mechanism together with an SO(3) family symmetry for leptons, broken only by the charged-lepton masses, I show that the three neutrinos of Majorana mass $m_0$ are split radiatively in two loops by a maximum finite calculable amount of order $10^{-9} m_0$. This is very suitable for dark matter and vacuum solar neutrino oscillatio

Veronica I. Marconi, Daniel Dominguez

We study the effect of thermal fluctuations in a vortex lattice driven in the periodic pinning of a Josephson junction array. The phase diagram current ($I$) vs. temperature ($T$) is studied. Above the critical current $I_c(T)$ we find a moving vortex lattice (MVL) with anisotropic Bragg peaks. For large currents $I\gg I_c(T)$, there is a melting transition

Giampiero Esposito, Cosimo Stornaiolo

For vacuum Maxwell theory in four dimensions, a supplementary condition exists (due to Eastwood and Singer) which is invariant under conformal rescalings of the metric, in agreement with the conformal symmetry of the Maxwell equations. Thus, starting from the de Donder gauge, which is not conformally invariant but is the gravitational counterpart of the Lore

M. Arnould, K. Takahashi

Nuclear astrophysics is that branch of astrophysics which helps understanding some of the many facets of the Universe through the knowledge of the microcosm of the atomic nucleus. In the last decades much advance has been made in nuclear astrophysics thanks to the sometimes spectacular progress in the modelling of the structure and evolution of the stars, in

S. D. Joglekar, A. Misra

We use finite field-dependent BRS transformations (FFBRS) to connect the Green functions in a set of two otherwise unrelated gauge choices. We choose the Lorentz and the axial gauges as examples. We show how the Green functions in axial gauge can be written as a series in terms of those in Lorentz gauges. Our method also applies to operator Green&#39;s funct

John T. Whelan, Joseph D. Romano

The geometry of two infinitely long lines of mass moving in a fixed circular orbit is considered as a toy model for the inspiral of a binary system of compact objects due to gravitational radiation. The two Killing fields in the toy model are used, according to a formalism introduced by Geroch, to describe the geometry entirely in terms of a set of tensor fi

F. M. Izrailev, A. A. Krokhin

We show that a mobility edge exists in 1D random potentials provided specific long-range correlations. Our approach is based on the relation between binary correlator of a site potential and the localization length. We give the algorithm to construct numerically potentials with mobility edge at any given energy inside allowed zone. Another natural way to gen

L. Santos, M. Lewenstein, J. I. Cirac, Y. Castin

We demonstrate that an appropriate sequence of laser pulses allows to condense a gas of trapped bosonic atoms into an arbitrary trap level. Such condensation is robust, can be achieved in experimentally feasible traps, and may lead to multistability and hysteresis phenomena.

R. E. Kastner

I defend my arguments in quant-ph/9806002, which have recently been criticized by L. Vaidman (quant-ph/9811092). I emphasize that the correct usage of the ABL rule applies not to a genuine counterfactual statement but rather to a conjunction of material conditionals. I argue that the only kind of valid counterfactual statement one can make using the ABL rule

G. Kaniadakis, A. Lavagno, M. Lissia, P. Quarati

Recent progresses in statistical mechanics indicate the Tsallis nonextensive thermostatistics as the natural generalization of the standard classical and quantum statistics, when memory effects and long-range forces are not negligible. In this framework, weakly nonextensive statistical deviations can strongly reduce the puzzling discrepancies between experim

W. Garcia Fuertes, J. Mateos Guilarte

The low energy dynamics of the vortices of the Abelian Chern-Simons-Higgs system is investigated from the adiabatic approach. The difficulties involved in treating the field evolution as motion on the moduli space in this system are shown. Another two generalized Abelian Higgs systems are discusssed with respect to their vortex dynamics at the adiabatic limi

W. Garcia Fuertes, J. Mateos Guilarte

Several issues concerning the self-dual solutions of the Chern-Simons-Higgs model are addressed. The topology of the configuration space of the model is analysed when the space manifold is either the plane or an infinite cylinder. We study the local structure of the moduli space of self-dual solitons in the second case by means of an index computation. It is

A. M. Khvedelidze, H. -P. Pavel

The method of reduction of a non-Abelian gauge theory to the corresponding unconstrained system is exemplified for SU(2) Yang-Mills field theory. The reduced Hamiltonian which describes the dynamics of the gauge invariant variables is presented in the form of a strong coupling expansion. The physical variables are separated into fields, which are scalars und

E. N. Bukina

It is shown that the difference between the magnetic moment results in the quark model with null instantons and semibosonized Nambu-Jona-Lasinio model lies in the description of the magnetic moment of the $ Λ$-hyperon.

A. Taruya

We study the adiabatic density perturbation in the {\it oscillating inflation}, proposed by Damour and Mukhanov. The recent study of the cosmological perturbation during reheating shows that the adiabatic fluctuation behaves like as the perfect fluid and no significant amplification occurs on super-horizon scales. In the oscillating inflation, however, the a

G. Piller, L. Ferreira, W. Weise

We discuss the close relation between shadowing in deep-inelastic lepton-nucleus scattering and diffractive photo- and leptoproduction of hadrons from free nucleons. We show that the magnitude of nuclear shadowing at small Bjorken-x, as measured by the E665 and NMC collaborations, is directly related to HERA data on the amount of diffraction in the scatterin

J. Z. Bai

Hadronic decays of the P-wave spin-triplet charmonium states χ_cJ (J=0,1,2) are studied using a sample of ψ(2S) decays collected by the BES detector operating at the BEPC storage ring. Branching fractions for the decays χ_c1 going to K_s^0 K^+ π^- + c.c., χ_c0 going to K_s^0 K_s^0, χ_c2 going to K_s^0 K_s^0, χ_c0 going to ϕϕ, χ_c2 going to ϕϕand χ_cJ going t

A. Barvinsky, A. Kamenshchik, C. Kiefer, I. Mishakov

We calculate the reduced density matrix for the inflaton field in a model of chaotic inflation by tracing out degrees of freedom corresponding to various bosonic fields. We find a qualitatively new contribution to the density matrix given by the Euclidean effective action of quantum fields. We regularise the ultraviolet divergences in the decoherence factor.

Mohammad Nouri-Zonoz, Naresh Dadhich, D. Lynden-Bell

By decomposing the Riemann curvature into electric and magnetic parts, a duality transformation, which involves interchange of active and passive electric parts, has recently been proposed. It was shown that the Schwarzschild solution is dual to the one that describes the Schwarzschild particle with cloud of string dust or a global monopole. Following the sa

L. Roters, S. Lubeck, K. D. Usadel

The Nagel-Schreckenberg traffic flow model shows a transition from a free flow regime to a jammed regime for increasing car density. The measurement of the dynamical structure factor offers the chance to observe the evolution of jams without the necessity to define a car to be jammed or not. Above the jamming transition the dynamical structure factor exhibit

B. Normand, D. F. Agterberg, T. M. Rice

LaCuO_2.5 is a system of coupled, two-chain, cuprate ladders which may be doped systematically by Sr substitution. Motivated by the recent synthesis of single crystals, we investigate theoretically the possibility of superconductivity in this compound. We use a model of spin fluctuation-mediated superconductivity, where the pairing potential is strongly peak

Y. Naveh, A. N. Korotkov, K. K. Likharev

We have derived a general formula describing current noise in multimode ballistic channels connecting source and drain electrodes with Fermi electron gas. In particular (at $eV\gg k_{B}T$), the expression describes the nonequilibrium &#39;&#39;shot&#39;&#39; noise, which may be suppressed by both Fermi correlations and space charge screening. The general for

D. V. Fil

Screening of the electric field of a test charge by monolayer and double-layer composite fermion systems is considered. It is shown that the electric field of the test charge is partly screened at distances much large then the magnetic length. The value of screening as a function of the distance depends considerably on the filling factor. The effect of varia

D. Tsch&#34;oke, G. Hensler, N. Junkes

We present X-ray observations of the interacting pair of galaxies NGC 4410a/b with the ROSAT HRI and PSPC. The ROSAT HRI images reveal a point-like source corresponding to NGC 4410a and an X-ray halo, extending 10&#34; from the nucleus toward the southeast. The halo emission accounts for ~1/3 (L_X=1.3x10^{41} erg s^{-1} in the 0.1 - 2.4 keV ROSAT band) of th

Rudy Wijnands, Michiel van der Klis, Erik-Jan Rijkhorst

We have discovered a 7.06+-0.08 Hz quasi-periodic oscillation (QPO) in the X-ray flux of the low-luminosity low-mass X-ray binary (LMXB) and atoll source 4U 1820-30. This QPO was only observable at the highest observed mass accretion rate, when the source was in the uppermost part of the banana branch, at a 2-25 keV luminosity of 5.4x10^37 erg/s (for a dista

Dean E. McLaughlin

A model is constructed for the mass and dynamics of M87 and the Virgo Cluster. Existing surface photometry of the galaxy, mass estimates from X-ray observations of the hot intracluster gas, and the velocity dispersions of early-type Virgo galaxies, all are used to constrain the run of dark matter density over radii to 2 Mpc in the cluster. The ``universal&#3

J. R. Primack, J. S. Bullock, A. A. Klypin, A. V. Kravtsov

This article concerns the formation and structure of dark matter halos, including (1) their radial density profiles, (2) their abundance, and (3) their merger rates. The last topic may be relevant to the nature of the small, bright, high-redshift galaxies discovered by the Lyman break technique. (1) Study of a statistical sample of galaxy-mass dark halos in

K. Hosomichi, Y. Sugawara

We explore the superstring theory on AdS_3 x S^3 x T^4 in the framework given in hep-th/9806194. We argue on the Hilbert space of "space-time CFT", and especially construct a suitable vacuum of this CFT from the physical degrees of freedom of the superstring theory in bulk. We first construct it explicitly in the case of p=1, and then present a proposal for

G. Quznetsov

The probabilities of point events in space 3 + 1 obey an equation of Dirac type. Masses, moments, energies, spins, etc. are the parameters of the probability distribution of such events. The terms and equations of quark-gluon theories turn out theoretically probabilistic terms and theorems. Confinement and asymptotic freedom are explained by behaviour of suc