November 1999 arXiv papers — page 21

O. Benichou, A. M. Cazabat, J. De Coninck, M. Moreau

We study the intrinsic friction of monolayers adsorbed on solid surfaces from a gas phase or vapor. Within the framework of the Langmuir model of delocalized adsorption, we calculate the resistance offered by the mobile adsorbate's particles to some impure tracer molecule, whose diffusive random motion is biased by a constant external force. We find that

I. V. Krive, A. S. Rozhavsky, E. R. Mucciolo, L. E. Oxman

In this work we study the transport properties of a finite Peierls-Fröhlich dielectric with a charge density wave of the commensurate type. We show that at low temperatures this problem can be mapped onto a problem of fractional charge transport through a finite-length correlated dielectric, recently studied by Ponomarenko and Nagaosa [Phys. Rev. Lett {\bf 8

T. H. Metcalf, Xiao Liu, R. O. Pohl

The internal friction of e-beam amorphous silicon was measured in a magnetic field between 0 and 6 T, from 1.5-20 K, and was found to be independent of the field to better than 8%. It is concluded that the low energy excitations observed in this experiment are predominantly atomic in nature.

L. S. Schulman

A model in which two weakly coupled systems maintain opposite running thermodynamic arrows of time is exhibited. Each experiences its own retarded electromagnetic interaction and can be seen by the other. The possibility of opposite-arrow systems at stellar distances is explored and a relation to dark matter suggested.

Hernan A. Makse

Many sedimentary rocks are formed by migration of sand ripples. Thin layers of coarse and fine sand are present in these rocks, and understanding how layers in sandstone are created has been a longstanding question. Here, we propose a mechanism for the origin of the most common layered sedimentary structures such as inverse graded climbing ripple lamination

Tetsuro Konishi

Intersection angles of stable and unstable manifolds for area preserving mappings are numerically calculated by extremely accurate computation. With the use of multiprecision library the values of angle as small as 10^{-400} are obtained. The singular dependence of the angle on the magnitude of hyperbolicity is confirmed. The power-law type prefactor with St

B. R. McNamara

The giant galaxies located at the centers of cluster cooling flows are frequently sites of vigorous star formation. In some instances, star formation appears to have been triggered by the galaxy's radio source. The colors and spectral indices of the young populations are generally consistent with short duration bursts or continuous star formation for dur

P. B. Tissera, A. Mosconi, D. G. Lambas

We report preliminar results on a chemical model implemented in a hydrodynamical cosmological code. We compute the metallicity of the gaseous component in galactic halos at different redshifts. The results compare reasonably well to observations. In particular, we show the predicted metallicity content of today-galaxy progenitors as a function of redshift an

G. Trinchieri, W. Pietsch

Two X-ray bright early type galaxies, selected for their unusually high X-ray to optical flux ratio, have been observed at high spatial resolution with the ROSAT HRI. Both sources are clearly extended (more than 250 kpc in radius), thus excluding a nuclear origin of the high X-ray emission. A small group of galaxies observed around IC 1262 could be the most

Jean-Marie Hameury, Jean-Pierre Lasota, Brian Warner

In the framework of the dwarf nova thermal-viscous disc instability model, we investigate the combined effects on the predicted dwarf nova lightcurves of irradiating the accretion disc and the secondary star and of evaporating the inner parts of the disc. We assume the standard values of viscosity. We confirm the suggestion by Warner (1998) that the large va

Eun-Joo Ahn, Gustavo Medina-Tanco, Peter L. Biermann, Todor Stanev

Introducing a simple Galactic wind model patterned after the solar wind we show that back-tracing the orbits of the highest energy cosmic events suggests that they may all come from the Virgo cluster, and so probably from the active radio galaxy M87. This confirms a long standing prediction, as well as a theoretical model for the radio galaxy jet emission of

Andrei M. Beloborodov

Power density spectra (PDSs) of long gamma-ray bursts provide useful information on GRBs, indicating their self-similar temporal structure. The best power-law PDSs are displayed by the longest bursts (T_90 > 100 s) in which the range of self-similar time scales covers more than 2 decades. Shorter bursts have apparent PDS slopes more strongly affected by stat

C. Hern'andez-Monteagudo, F. Atrio-Barandela, J. P. Mücket

If the mean properties of clusters of galaxies are well described by the entropy-driven model, the distortion induced by the cluster population on the blackbody spectrum of the Cosmic Microwave Background radiation is proportional to the total amount of intracluster gas while temperature anisotropies are dominated by the contribution of clusters of about 10^

K. Hamaguchi, H. Terada, A. Bamba, K. Koyama

Hard X-ray emissions from a Herbig Be star MWC297 were discovered in three separate observations spanning 5 days in April 1994 with the Advanced Satellite for Cosmology and Astrophysics (ASCA). An X-ray flare was found at the beginning of the second observation with a maximum luminosity of 4.9E32 ergs/s, which is five times larger than that of the quiescent

R. Cowsik

It is suggested that modern techniques of radio ranging when applied to study the motion of the Moon, can improve the accuracy of tests of relativistic gravitation obtained with currently operating laser ranging techniques. Other auxillary information relevant to the Solar system would also emerge from such a study.

Luigi Guzzo

I review the current status of studies of the large-scale structure of the Universe using redshift surveys of galaxies and clusters of galaxies. I first summarise the advances we have made in our knowledge of the cosmography of the z<0.2 Universe during the last 25 years, as well as the status of the major surveys in progress. The question of how the &#34;a

Vassiliki Kalogera

The coalescence of close binary systems with two compact objects (neutron stars and black holes) are considered to be promising sources of gravitational waves for the currently built laser interferometers. Here, I review the current Galactic coalescence estimates derived both theoretically and empirically. I discuss the uncertainties involved as well as ways

Sedigheh Deldar

The potentials and string tensions between static sources in a variety of representations (fundamental, 8, 6, 15-antisymmetric, 10, 27 and 15-symmetric) have been computed by measuring Wilson loops in pure gauge SU(3). The simulations have been done primarily on anisotropic lattices, using a tadpole improved action improved to O(a_{s}^4). A range of lattice

T. Asano, H. Nojiri, Y. Inagaki, J. P. Boucher

A new elementary-excitation, the so called &#34;breather excitation&#34;, is observed directly by millimeter-submillimeter wave electron spin resonance (ESR) in the Heisenberg quantum spin-chain Cu benzoate, in which a field-induced gap is found recently by specific heat and neutron scattering measurements. Distinct anomalies were found in line width and in

Andrew W. Blain, D. T. Frayer, J. J. Bock, N. Z. Scoville

The redshifted spectral line radiation emitted from both atomic fine-structure and molecular rotational transitions in the interstellar medium (ISM) of high-redshift galaxies can be detected in the centimetre, millimetre and submillimetre wavebands. Here we predict the counts of galaxies detectable in an array of molecular and atomic lines. This calculation

Boris Botvinnik, Christine Escher

The paper is withdrawn due to some errors.

D. Vretenar, P. Finelli, A. Ventura, G. A. Lalazissis

Parity violating elastic electron scattering on neutron-rich nuclei is described in the framework of relativistic mean-field theory. Self-consistent ground state density distributions of Ne, Na, Ni and Sn isotopes are calculated with the relativistic Hartree- Bogoliubov model, and the resulting neutron radii are compared with available experimental data. For

A. N. Ivanov, H. Oberhummer, N. I. Troitskaya, M. Faber

The cross sections for the M1-capture n + p -> D + gamma, the photo-magnetic and anti-neutrino disintegration of the deuteron are evaluated in the relativistic field theory model of the deuteron (RFMD). The cross section for M1-capture is evaluated by taking into account the contributions of chiral one-meson loop corrections and the Delta(1232) resonance. Th

Emmanuel Lanzmann

In [ZH], R.B. Zhang found a way to link certain formal deformations of the Lie algebra o(2l+1) and the Lie superalgebra osp(1,2l). The aim of this article is to reformulate the Zhang transformation in the context of the quantum enveloping algebras &#34;à la&#34; Drinfeld-Jimbo and to show how this construction can explain the main theorem of [GL2]: the annih

Denis V. Juriev

This short note is devoted to the representative dynamics, which realizes a link between the theory of controlled systems and representation theory. Dynamical inverse problem of representation theory for controlled systems is considered: to solve it means to correspond a representative dynamics to the controlled system.

I. I. Bigi, A. I. Sanda

A comprehensive program of \cp~studies in heavy flavour decays has to go beyond observing large \cp asymmetries in nonleptonic B decays and finding that the sum of the three angles of the KM triangle is consistent with 180$^{\circ}$. There are many more correlations between observables encoded in the KM matrix; those can be expressed through five KM triangle

Peter Leifer

Intrinsic unfication of quantum theory and general relativity based on the underlying quantum dynamics of fundamental field has been proposed.

K. Srinivasan, T. Padmanabhan

We outline a different method of describing scalar field particle production in a uniform electric field. In the standard approach, the (analytically continued) harmonic oscillator paradigm is important in describing particle production. However, there is another gauge in which the particle production process has striking similarities with the one used to de

S. Brazovskii, A. Larkin

A model of local metastable states due to the pinning induces plastic deformations allows to describe the nonlinear I-V curves in sliding density waves -DW. With increasing the DW velocity v, the metastable states of decreasing lifetimes ~1/v are accessed. The characteristic second threshold field is reached when configurations of shortest life time are acce

Tai Kai Ng

We show in this paper an interesting relation between elementary and topological excitations in the antiferromagnetic and d-wave superconducting phases of the t-J model at two dimenions. The topological spin and charge excitations in one phase have the same dynamics as elementary excitations in the other phase, except the appearance of energy gaps. Moreover,

Ken&#39;ichi Takano

We study mixed quantum spin chains consisting of two kinds of spins with magnitudes, s_a and s_b. The spins are arrayed as s_a-s_a-s_b-s_b in a unit cell and the exchange couplings are accordingly periodic with period 4. The spin Hamiltonian is mapped onto a nonlinear $σ$ model based on the general formula for periodic inhomogeneous spin chains. The gapless

Z. Y. Weng, D. N. Sheng, C. S. Ting

It is shown that the isotropic dispersion relation, line shape of the spectral function, and remnant Fermi surface found in recent photoemission experiment in insulating Ca_2CuO_2Cl_2 by Ronning et al.(Science, 282, 2067 (1998)) can be consistently explained by a direct holon hopping process which fundamentally undermines the conventional self-consistent Bor

S. D. Van Dyk, K. W. Weiler, M. J. Montes, R. A. Sramek

Detailed radio observations of extragalactic supernovae are critical to obtaining valuable information about the nature and evolutionary phase of the progenitor star in the period of a few hundred to several tens-of-thousands of years before explosion. Additionally, radio observations of old supernovae (>20 years) provide important clues to the evolution of

Mark A. Walker

Extreme Scattering Events are radio-wave lensing events caused by AU-sized concentrations of ionised gas. Although they were discovered more than a decade ago we still have no clear picture of the physical nature of the lenses. To discriminate between the various models, we need to amass more information on multiple imaging phenomena. Pulsars are perfect tar

W. F. Welsh

Many AGN exhibit a highly variable luminosity. Some AGN also show a pronounced time delay between variations seen in their optical continuum and in their emission lines. In effect, the emission lines are light echoes of the continuum. This light travel-time delay provides a characteristic radius of the region producing the emission lines. The cross correlati

N. Prantzos, S. Boissier

We study the relations between luminosity and chemical abundance profiles of spiral galaxies, using detailed models for the chemical and spectro-photometric evolution of galactic discs. The models are ``calibrated&#39;&#39; on the Milky Way disc and are successfully extended to other discs with the help of simple ``scaling&#39;&#39; relations, obtained in th

C. Megan Urry, Riccardo Scarpa, Matthew O&#39;Dowd, Renato Falomo

We have used the HST WFPC2 camera to survey 132 BL Lac objects comprising seven complete radio-, X-ray-, and optically-selected samples. We obtained useful images for 110 targets spanning the redshift range 0 < z < 1.3. In two thirds of the BL Lac images, host galaxies are detected, including nearly all for z < 0.5 (58 of 63). The highest redshift host galax

Qaisar Shafi, Zurab Tavartkiladze

We discuss how realistic supersymmetric models can be constructed by employing an anomalous ${\cal U}(1)$ flavor symmetry which also mediates supersymmetry breaking. A judicious choice of ${\cal U}(1)$ charges enables the first two squark families to be sufficiently heavy ($\stackrel{>}{_\sim}10$ TeV), so that flavor changing neutral currents as well as dime

N. Mebarki, A. Maireche, M. Haouchine

Withdrawn by arXiv administration because authors have forged affiliations and acknowledgements, and have not adequately responded to charges [hep-th/9912039] of unattributed use of verbatim material.

N. Mebarki, A. Maireche

Withdrawn by arXiv administration because authors have forged affiliations and acknowledgements, and have not adequately responded to charges [hep-th/9912039] of unattributed use of verbatim material.

N. Mebarki, A. Maireche

Withdrawn by arXiv administration because authors have forged affiliations and acknowledgements, and have not adequately responded to charges [hep-th/9912039] of unattributed use of verbatim material.

Adan Cabello

Entanglement swapping between Einstein-Podolsky-Rosen (EPR) pairs can be used to generate the same sequence of random bits in two remote places. A quantum key distribution protocol based on this idea is described. The scheme exhibits the following features. (a) It does not require that Alice and Bob choose between alternative measurements, therefore improvin

N. Mebarki, A. Maireche, A. Boudine, A. Benslama

Withdrawn by arXiv administration because authors have forged affiliations and acknowledgements, and have not adequately responded to charges [hep-th/9912039] of unattributed use of verbatim material.

N. Mebarki, A. Maireche

Withdrawn by arXiv administration because authors have forged affiliations and acknowledgements, and have not adequately responded to charges [hep-th/9912039] of unattributed use of verbatim material.

N. Mebarki, A. Maireche

Withdrawn by arXiv administration because authors have forged affiliations and acknowledgements, and have not adequately responded to charges [hep-th/9912039] of unattributed use of verbatim material.

Simon Davis

The quantum cosmology of a higher-derivative derivative gravity theory arising from the heterotic string effective action is reviewed. A new type of Wheeler-DeWitt equation is obtained when the dilaton is coupled to the quadratic curvature terms. Techniques for solving the Wheeler-DeWitt equation with appropriate boundary conditions shall be described, and i

Sergio M. C. V. Goncalves

Brady, Creighton and Thorne have argued that, in numerical relativity simulations of the inspiral of binary black holes, if one uses lapse and shift functions satisfying the ``minimal strain equations&#39;&#39; (MSE), then the coordinates might be kept co-rotating, the metric components would then evolve on the very slow inspiral timescale, and the computati

Alan Heavens, Raul Jimenez, Ofer Lahav

We present a method for radical linear compression of datasets where the data are dependent on some number $M$ of parameters. We show that, if the noise in the data is independent of the parameters, we can form $M$ linear combinations of the data which contain as much information about all the parameters as the entire dataset, in the sense that the Fisher in

Roberto Emparan, Gary T. Horowitz, Robert C. Myers

To test recent ideas about lower dimensional gravity bound to a brane, we construct exact solutions describing black holes on two-branes in four dimensions. We find that 2+1 gravity is indeed recovered at large distances along the brane, although there are significant deviations at smaller scales. Large black holes appear as flattened &#34;pancakes&#34;, wit

U. P. Sukhatme, M. N. Sergeenko

We derive the semiclassical WKB quantization condition for obtaining the energy band edges of periodic potentials. The derivation is based on an approach which is much simpler than the usual method of interpolating with linear potentials in the regions of the classical turning points. The band structure of several periodic potentials is computed using our se

Adan Cabello

Kent&#39;s conclusion that ``non-contextual hidden variable theories cannot be excluded by theoretical arguments of the Kochen-Specker type once the imprecision in real world experiments is taken into account&#39;&#39; [Phys. Rev. Lett. 83, 3755 (1999)], is criticized. The Kochen-Specker theorem just points out that it is impossible even conceive a hidden va

Adan Cabello

Two approaches to extend Hardy&#39;s proof of nonlocality without inequalities to maximally entangled states of bipartite two-level systems are shown to fail. On one hand, it is shown that Wu and co-workers&#39; proof [Phys. Rev. A 53, R1927 (1996)] uses an effective state which is not maximally entangled. On the other hand, it is demonstrated that Hardy&#39

Adan Cabello

A recent proposal to experimentally test quantum mechanics against noncontextual hidden-variable theories [Phys. Rev. Lett. 80, 1797 (1998)] is shown to be related with the smallest proof of the Kochen-Specker theorem currently known [Phys. Lett. A 212, 183 (1996)]. This proof contains eighteen yes-no questions about a four-dimensional physical system, combi

Bo-Sture Skagerstam

This is the written version of lectures presented at &#34;The 17th Symposium on Theoretical Physics - Applied Field Theory&#34;, 29 June - 1 July, 1998, the Sangsan Mathematical Science Building, Seoul National University, Seoul, Korea.

K. T. McDonald

We are exploring the feasibility of a neutrino factory based on a muon storage ring. In this, beams of nu_mu and nubar_e arise from the decay of mu- particles (or alternatively, nubar_mu and nu_e from mu+). The muons come from the decay of low-energy pions produced by a megawatt proton beam incident on a nuclear target. The muons are captured into a magnetic

A. N. Ivanov, H. Oberhummer, N. I. Troitskaya, M. Faber

The relativistic field theory model of the deuteron (RFMD) is reformulated from the first principles of QCD. The deuteron appears as a neutron-proton collective excitation, i.e. a Cooper np-pair, induced by a phenomenological local four-nucleon interaction in the nuclear phase of QCD. The RFMD describes the deuteron coupled to hadrons through one-nucleon loo

Izu Vaisman

The transversal twistor space of a foliation F of an even codimension is the bundle ZF of the complex structures of the fibers of the transversal bundle of F. On ZF, there exists a foliation F&#39; by covering spaces of the leaves of F, and any Bott connection of F produces an ordered pair (I,J) of transversal almost complex structures of F&#39;. The existen

Denka Kutzarova, Denny H. Leung

A Banach space X with closed unit ball B is said to have property 2-beta, repsectively 2-NUC if for every \ep > 0, there exists δ> 0 such that for every \ep-separated sequence (x_n) in the unit ball B, and every x in B, there are distinct indices m and n such that ||x + x_m + x_n|| < 3(1 - δ), respectively, ||x_m + x_n|| < 2(1 - δ). It is shown that a Banach

Shihoko Ishii, Yuri Prokhorov

This paper studies hypersurface exceptional singularities in $\mathbb C^n$ defined by non-degenerate function. For each canonical hypersurface singularity, there exists a weighted homogeneous singularity such that the former is exceptional if and only if the latter is exceptional. So we study the weighted homogeneous case and prove that the number of weights

K. J. Juge, J. Kuti, C. J. Morningstar

Surface critical phenomena and the related onset of Goldstone modes probe the fundamental properties of the confining flux in Quantum Chromodynamics. New ideas on surface roughening and their implications for lattice studies of quark confinement are presented. Problems with the oversimplified string description of the Wilson flux sheet are discussed.

G. Braun, H. Fischer, J. Franz, A. Grunemaier

A new TDC chip has been developed for the COMPASS experiment at CERN. The resulting ASIC offers an unprecedented degree of flexibility and functionality. Its capability to handle highest hit and trigger input rates as well as its low power consumption makes it an ideal tool for future collider and fixed target experiments. First front-end boards equipped wit

Bruce J. King

Both muon colliders and non-colliding muon storage rings using muon collider technology have the potential to become the first true ``neutrino factories&#39;&#39;, with uniquely intense and precisely characterized neutrino beams that could usher in a new era of high rate and long baseline neutrino physics studies at accelerators. This paper gives an overview

Jorge F. de Troconiz

The phenomenology of the electroweak symmetry breaking sector is expected to involve resonances decaying preferentially into heavy fermions. Three recent CDF analyses are reviewed and used to constrain Higgs and Technicolor models.

S. Rouziere, S. Ravy, S. Brazovskii, J. -P. Pouget

We present an x-ray study of doped charge density waves systems. When a 2k_f-charge density wave is strongly pinned to impurities, an interference effect gives rise to an asymmetry between the intensities of the +2k_f and -2k_f satellite reflections. Moreover, profile asymmetry of the satellite reflections indicates the existence of Friedel oscillations (FOs

Jon Links, Angela Foerster

A new model for a spin 1/2 ladder system with two legs is introduced. It is demonstrated that this model is solvable via the Bethe ansatz method for arbitrary values of the rung coupling J. This is achieved by a suitable mapping from the Hubbard model with appropriate twisted boundary conditions. We determine that a phase transition between gapped and gaples

V. Brunel, K. Oerding, F. van Wijland

We formulate directed percolation in (1+1) dimensions in the language of a reaction-diffusion process with exclusion taking place in one space dimension. We map the master equation that describes the dynamics of the system onto a quantum spin chain problem. From there we build an interacting fermionic field theory of a new type. We study the resulting theory

Horacio E. Camblong, Peter M. Levy

The electrical resistivity of a pure sample of a thin metallic film is found to depend on the boundary conditions. This conclusion is supported by a free-electron model calculation and confirmed by an ab initio relativistic Korringa-Kohn-Rostoker computation. The low-temperature resistivity is found to be zero for a free-standing film (reflecting boundary co

D. R. Goncalves, R. M. L. Corradi, E. Villaver, A. Mampaso

We present new results of a program aimed at studying the physical properties, origin and evolution of those phenomena which go under the somewhat generic definition of &#34;low-ionization, small-scale structures in PNe&#34;. We have obtained morphological and kinematical data for 10 PNe, finding low-ionization structures with very different properties relat

Henk Hoekstra, Marijn Franx, Konrad Kuijken

We have measured for the first time the weak lensing signal due to groups of galaxies. The groups are at intermediate redshifts, and have been identified in the CNOC2 field survey, which was kindly made available by Ray Carlberg and Howard Yee. The ensemble averaged group velocity dispersion, based on a preliminary selection of 59 groups, is found to be sigm

Lucia M. Franco, Bennett Link, Richard I. Epstein

Gravitational, magnetic and superfluid forces can stress the crust of an evolving neutron star. Fracture of the crust under these stresses could affect the star&#39;s spin evolution and generate high-energy emission. We study the growth of strain in the crust of a spinning down, magnetized neutron star and examine the initiation of crust cracking (a {\em sta

L. L. Leeuw, A. E. Sansom, E. I. Robson

We present SCUBA imaging and photometry of the elliptical galaxy NGC 4374. The imaging observations are used to examine the spatial distribution of thermal emission from dust and the radio to infrared continuum spectrum. In the SCUBA 850 um image, the galaxy is found to be a point source, constraining the emission to less than 15&#39;&#39; (1.5 kpc for a dis

Marc Kamionkowski, Andrew R. Liddle

N-body simulations of structure formation with scale-invariant primordial perturbations show significantly more virialized objects of dwarf-galaxy mass in a typical galactic halo than are observed around the Milky Way. We show that the dearth of observed dwarf galaxies could be explained by a dramatic downturn in the power spectrum at small distance scales.

M. C. Britton

In radio astronomy the polarimetric properties of radiation are often modified during propagation and reception. Effects such as Faraday rotation, receiver cross-talk, and differential amplification act to change the state of polarized radiation. A general description of such transformations is useful for the investigation of these effects and for the interp

B. Dutta, Sechul Oh

In the light of recent experimental data from the CLEO Collaboration we study, the decays of B mesons to a pair of pseudoscalar (P) mesons, and a vector (V) meson and a pseudoscalar meson, in the framework of factorization. In order to obtain the best fit for the recent CLEO data, we critically examine the values of several input parameters to which the pred

Ruben Minasian, Dimitrios Tsimpis

We present a formal supersymmetric solution of type IIB supergravity generalizing previously known solutions corresponding to D3 branes to geometries without an orthogonal split between parallel and transverse directions. The metric is given implicitly as one with respect to which a certain connection is compatible. The case of the deformed conifold is discu

Kentaro Nagai, Tsutomu Momoi, Kenn Kubo

We studied magnetic properties of the double exchange (DE) model with S=1/2 localized spins at T=0, using exact diagonalization in the framework of the dynamical mean field theory. Obtained phase diagram contains ferromagnetic, antiferromagnetic and paramagnetic phases. Comparing the phase diagram with that of the DE model with classical localized spins, we

H. Davoudiasl, J. L. Hewett, T. G. Rizzo

We explore the consequences of placing the Standard Model gauge fields in the bulk of the recently proposed localized gravity model of Randall and Sundrum. We find that the Kaluza Klein excitations of these fields are necessarily strongly coupled and we demonstrate that current precision electroweak data constrain the lowest states to lie above $\simeq 23$ T

Jacques Distler, Frederic Zamora

We study the SU(3)-invariant relevant deformation of D=4 N=4 SU(N) gauge theory at large N using the AdS/CFT correspondence. At low energies, we obtain a nonsupersymmetric gauge theory with three left-handed quarks in the adjoint of SU(N). In terms of the five dimensional gauged supergravity, there is an unstable critical point in the scalar potential for fl

J. Ambjorn, Y. M. Makeenko, J. Nishimura, R. J. Szabo

We describe a unitary matrix model which is constructed from discrete analogs of the usual projective modules over the noncommutative torus and use it to construct a lattice version of noncommutative gauge theory. The model is a discretization of the noncommutative gauge theories that arise from toroidal compactification of Matrix theory and it includes a re

K. Jedamzik, V. Katalinic, A. V. Olinto

Spatially varying primordial magnetic fields may be efficiently dissipated prior to the epoch of recombination due to the large viscosity of the baryon-photon fluid. We show that this dissipation may result in observable chemical potential mu and Compton y distortions in the cosmic microwave background radiation (CMB) spectrum. Current upper limits on mu and

Miguel A. Aloy, Ewald Mueller, Jose M. Ibanez, Jose M. Marti

Using a collapsar progenitor model of MacFadyen & Woosley we have simulated the propagation of an axisymmetric jet through a collapsing rotating massive star with the GENESIS multi-dimensional relativistic hydrodynamic code. The jet forms as a consequence of an assumed (constant or variable) energy deposition in the range $10^{50}$ erg s$^{-1}$ to $10^{51}$

A. Giveon, D. Kutasov

We study little string theory in a weak coupling limit defined in \gk.

David H Lyth

We consider the abundance of gravitinos created from the vacuum fluctuation, in a class of `new&#39; inflation models for which global supersymmetry is a good approximation. Immediately after inflation, gravitinos are produced, with number density determined by equations recently presented by Kallosh et. al. (hep-th/9907124) and Giudice et. al. (hep-ph/99075

B. Julia, S. Silva

Supergravities are usually presented in a so-called 1.5 order formulation. Here we present a general scheme to derive pure 1^{st} order formulations of supergravities from the 1.5 order ones. The example of N_4=1 supergravity will be rederived and new results for N_4=2 and N_11=1 will be presented. It seems that beyond four dimensions the auxiliary fields in

Fumiaki Morikoshi

When an entangled state is transformed into another one with probability one by local operations and classical communication, the quantity of entanglement decreases. This letter shows that entanglement lost in the manipulation can be partially recovered by an auxiliary entangled pair. As an application, a maximally entangled pair can be obtained from two par

D. Kunth, G. Ostlin

Metallicity is a key parameter that controls many aspects in the formation and evolution of stars and galaxies. In this review we focus on the metal deficient galaxies, in particular the most metal-poor ones, because they play a crucial role in the cosmic scenery. We first set the stage by discussing the difficult problem of defining a global metallicity and

M. J. Bijlsma, B. A. Heringa, H. T. C. Stoof

We consider a mixture of a single-component Bose gas and a two-component Fermi gas at temperatures where the Bose gas is almost fully condensed. In such a mixture, two fermionic atoms can interact with each other by exchanging a phonon that propagates through the Bose condensate. We calculate the interaction potential due to this mechanism and determine the

N. O. Agasian, I. A. Shushpanov

The low-energy QCD theorems are generalized in the presence of a constant magnetic field H. Two-loop approximation for the vacuum energy density in the framework of the chiral perturbation theory was obtained and the quark and gluon condensates were found as the functions of H.

L. Viverit, C. J. Pethick, H. Smith

We calculate the phase diagram for dilute mixtures of bosons and fermions at zero temperature. The linear stability conditions are derived and related to the effective boson-induced interaction between the fermions. We show that in equilibrium there are three possibilities: a) a single uniform phase, b) a purely fermionic phase coexisting with a purely boson

A. J. Buras, P. Gambino, U. Haisch

We calculate the O(alpha_s) corrections to the Z^0-penguin and electroweak box diagrams relevant for non-leptonic Delta F = 1 decays with F = S, B. This calculation provides the complete O(alpha_w alpha_s) and O(alpha_w alpha_s sin^2 theta_w m_t^2) corrections (alpha_w = alpha/sin^2 theta_w) to the Wilson coefficients of the electroweak penguin four quark op

F. C. Khanna, E. Truhlik

We construct weak axial one-boson exchange currents for the Bethe-Salpeter equation, starting from chiral Lagrangians of the N-Δ(1236)-pi-rho-a_1-omega system. The currents fulfil the Ward-Takahashi identities and the matrix element of the full current between the two-body solutions of the Bethe-Salpeter equation satisfies the PCAC constraint exactly.

J. Rehacek, J. Perina, P. Facchi, S. Pascazio

The distorsion of a spontaneous downconvertion process caused by an auxiliary mode coupled to the idler wave is analyzed. In general, a strong coupling with the auxiliary mode tends to hinder the downconversion in the nonlinear medium. On the other hand, provided that the evolution is disturbed by the presence of a phase mismatch, the coupling may increase t

J. Goryo

We have investigated the vortex in chiral superconductors, especially in p-wave case. In chiral superconductors the Cooper pair has orbital angular momentum hence U(1), parity (P) and time reversal symmetry (T) are broken simultaneously. We have found that the vortex has fractional charge and fractional angular momentum which comes from P- and T-violation. T

Noriaki Kitazawa, Nobuhito Maru, Nobuchika Okada

We propose a simple model of dynamical supersymmetry breaking in the context of minimal supergravity with gauged $U(1)_R$ symmetry. The model is based on the gauge group $SU(2) \times U(1)_R$ with three matters. Since the $U(1)_R$ symmetry is gauged, the Fayet-Iliopoulos D-term appears due to the symmetry of supergravity. On the other hand, the superpotentia

R. J. C. Spreeuw, D. Voigt, B. T. Wolschrijn, H. B. van Linden van den Heuvell

We discuss an experimental scheme to create a low-dimensional gas of ultracold atoms, based on inelastic bouncing on an evanescent-wave mirror. Close to the turning point of the mirror, the atoms are transferred into an optical dipole trap. This scheme can compress the phase-space density and can ultimately yield an optically-driven atom laser. An important

Yuji Ohta

In contrast with the classical gauge group cases, any method to prove exactly the scaling relation which relates moduli and prepotential is not known in the case of exceptional gauge groups. This paper provides a direct method to establish this relation by using Picard-Fuchs equations. In particular, it is shown that the scaling relation found by Ito in N=2

V. Buat, J. Donas, B. Milliard, C. Xu

We have cross-correlated Far Infrared (IRAS) and UV (FOCA) observations of galaxies to construct a sample of FIR selected galaxies with a UV observation at 0.2 microns. The FIR and UV properties of this sample are compared to the mean properties of the local Universe deduced from the luminosity distributions at both wavelengths. Almost all the galaxies of ou

K. Kohri, S. Nagataki

We have investigated the relation of the direction of the momentum among the matter, neutrino, and proto-neutron star in a collapse-driven supernova in order to discuss the pulsar kick. In particular, we have investigated the effects of the pulsar motion on the explosion, which are neglected in the previous study. As a result, it is suggested that the direct

Michael Efroimsky

A body dissipates energy when it freely rotates about any axis different from principal. This entails relaxation, i.e., decrease of the rotational energy, with the angular momentum preserved. The spin about the major-inertia axis corresponds to the minimal kinetic energy, for a fixed angular momentum. Thence one may expect comets and asteroids (as well as sp

M. T. Murphy, J. K. Webb, I. S. Heng

The mechanism for gamma ray bursters and the detection of gravitational waves (GWs) are two outstanding problems facing modern physics. Many models of gamma ray bursters predict copious GW emission, so the assumption of an association between GWs and GRBs may be testable with existing bar GW detector data. We consider Weber bar data streams in the vicinity o