January 1998 arXiv papers — page 11

Mayumi Aoki, Noriyuki Oshimo

We study a decay rate asymmetry of the top quark in the supersymmetric standard model, taking into account the constraints from the electric dipole moments of the neutron and the electron. One CP-violating phase contained in the mass-squared matrices of squarks and sleptons is allowed to have an unsuppressed value, even if their masses are of order 100 GeV.

A. S. Kapoyannis, C. N. Ktorides, A. D. Panagiotou

We extend the Statistical Bootstrap Model (SBM) in order to describe hadronic systems which carry strangeness. We establish that the hadronic phase can exist only in a region of the three-dimensional space of temperature, up-down and strange chemical potentials, which is bounded by a critical critical surface. We first employ the usual version of the SBM, wh

N. Hammon, A. Dumitru, H. Stoecker, W. Greiner

The transverse momentum distribution of prompt photons coming from the very early phase of ultrarelativistic heavy ion collisions for the RHIC and LHC energies is calculated by means of perturbative QCD. We calculate the single photon cross section ($A+B\to γ+X$) by taking into account the partonic sub processes $q+ \bar{q}\to γ+g$ and $q+g\toγ+q$ as well as

J. Rizek, V. Brabec, O. Dragoun, M. Rysavy

The influence of the residual T atoms appearing after the decay of T_2 molecule on the beta-spectrum shape is considered. Recent experiments performed in Mainz, Troitsk, and Livermore are briefly reviewed from this viewpoint. Aspects connected with the possible time dependent change of the tritium source composition are discussed.

Ali Al-Naghmoush, Murat Özer, M. O. Taha

We impose the condition that the eigenvalues of the mass matrix in the shifted Lagrangian density be positive at ϕ=ϕ_{0}, the vacuum expectation value of the scalar field. Using the one-loop effective potential of the standard model, this condition leads to an upper bound on the Higgs boson mass m_{H}: m_{H}<230GeV, for a top quark mass of 175GeV.

S. Umisedo, H. Toki, H. Suganuma

We study the properties of the QCD vacuum in the dual Ginzburg-Landau theory, where QCD-monopole condensation leads to the linear confinement potential. Using the effective potential, we find monopole dominance for chiral-symmetry breaking. The effective mass of off-diagonal (charged) gluons is estimated as $M_{ch} \simeq 1.31$ GeV. The gluon condensate is c

Robert G. Edwards, Urs M. Heller, Rajamani Narayanan

We study the spectral flow of the hermitian Wilson-Dirac operator $\ham(m)$ as a function of $m$ in smooth SU(2) instanton backgrounds on the lattice. For a single instanton background with Dirichlet boundary conditions on $\ham(m)$, we find a level crossing in the spectral flow of $\ham(m)$, and we find the shape of the crossing mode at the crossing point t

Vicente Azcoiti

We show how all the contributions to the determinant of the Dirac-Kogut-Susskind operator of QCD at finite temperature containing a net number of Polyakov loops become irrelevant in the infinite volume limit. We discuss also on two of the most interesting physical implications of this result: i) the restoration of the Polyakov symmetry in the full theory wit

W. Lee, D. Weingarten

We evaluate the valence approximation to the mass of scalar quarkonium and to the mixing energy between scalar quarkonium and the lightest scalar glueball for a range of different lattice sizes and quark masses. Our results support the identification of $f_0(1710)$ as the lightest scalar glueball.

Robin Devenish

Recent measurements of unpolarised and polarised nucleon structure functions and F_2(gamma) are reviewed. The implications for QCD and the gluon momentum distribution are discussed. The status of the understanding of the total virtual-photon proton total cross-section in the transition region between real photoproduction and deep-inelastic scattering is summ

K. A. Bronnikov, G. Clément, C. P. Constantinidis, J. C. Fabris

We study the structure and stability of the recently discussed spherically symmetric Brans-Dicke black-hole type solutions with an infinite horizon area and zero Hawking temperature, existing for negative values of the coupling constant $ω$. These solutions split into two classes: B1, whose horizon is reached by an infalling particle in a finite proper time,

A. Geitner, M. Hanauske, E. Hitzer

Regarding Pauli&#39;s matrices as proper Higgs fields one can deduce an effective(!) approximation for gravity in flat space. In this work we extend this approximation up to the second order. Reaching complete agreement in the special case of gravitational waves. Unification in view, we introduce isospinorial degrees of freedom. In this way the mass spectrum

Arkadii Popov

The possibility of the cosmic string creation by the vacuum fluctuations of quantum fields in the self-consistent semiclassical theory of gravity is discussed. We use the approximate method for obtaining vacuum expectation value of the renormalized stress-energy tensor of conformally invariant quantum fields in static cylindrically symmetric spacetimes. We h

Murat Özer

We attempt to treat the very early Universe according to quantum mechanics. Identifying the scale factor of the Universe with the width of the wave packet associated with it, we show that there cannot be an initial singularity and that the Universe expands. Invoking the correspondence principle, we obtain the scale factor of the Universe and demonstrate that

Remo Garattini

We conjecture that the neutral black hole pair production is related to the vacuum fluctuation of pure gravity via the Casimir-like energy. Implications on the foam-like structure of spacetime are discussed.

S. Datta, S. Redner

We investigate clogging in depth filtration, in which a dirty fluid is ``cleaned&#39;&#39; by the trapping of dirt particles within the pore space during flow through a porous medium. This leads to a gradient percolation process which exhibits a power law distribution for the density of trapped particles at downstream distance x from the input. To achieve a

T. Jungwirth, A. H. MacDonald

Spin-bottlenecks are created in magnetic-tunnel-junction devices by spatial inhomogeneity in the relative resistances for up and down spins. We propose a simple electrical circuit model for these devices which incorporates spin-bottleneck effects and can be used to calculate their overall resistance and magnetoresistance. The model permits a simple understan

Peter Kopietz

We calculate the self-energy of two-dimensional fermions that are coupled to transverse gauge fields, taking two-loop corrections into account. Given a bare gauge field propagator that diverges for small momentum transfers q as 1 / q^{eta}, 1 < eta < 2, the fermionic self-energy without vertex corrections vanishes for small frequencies omega as Sigma (omega)

A. E. Koshelev, V. M. Vinokur

Destruction of the vortex lattice by random point pinning is considered as a mechanism of the ``second peak&#39;&#39; transition observed experimentally in weakly coupled layered high temperature superconductors. The transition field separating the topologically ordered quasilattice from the amorphous vortex configuration is strongly influenced by the layere

E. A. Bartnik, M. Bednarz

This paper presents a theoretical model intended to address the question of energy transfer in two-dimensional molecular assemblies such as Scheibe aggregates. A new phonon-exciton interaction is introduced to explain the exciton width in J aggregates. It is shown that the long range energy transport can occur for weakly interacting acceptors.

Albert Compte, Jean-Philippe Bouchaud

Diffusion in a one dimensional random force field leads to interesting localisation effects, which we study using the equivalence with a directed walk model with traps. We show that although the average dispersion of positions $\bar{< x^2 > - < x > ^2}$ diverges for long times, the probability that two particles occupy the same site tends to a finite constan

Kiran M. Kolwankar, Anil D. Gangal

New kind of differential equations, called local fractional differential equations, has been proposed for the first time. They involve local fractional derivatives introduced recently. Such equations appear to be suitable to deal with phenomena taking place in fractal space and time. A local fractional analog of Fokker-Planck equation has been derived starti

M. Alimohammadi, V. Karimipour, M. Khorrami

We define a family of asymmetric processes for particles on a one-dimensional lattice, depending on a continuous parameter $λ\in [0,1] $, interpolating between the completely asymmetric processes [1] (for $λ=1$) and the n=1 drop-push models [2] (for $ λ=0$). For arbitrary $\la$, the model describes an exclusion process, in which a particle pushes its right n

G. Seibold, E. Sigmund, V. Hizhnyakov

The Kotliar-Ruckenstein slave-boson scheme is used to allow for an unrestricted variation of the bosonic and fermionic fields on the saddle-point level. Various inhomogeneous solutions, such as spin polarons and domain walls are discussed within the two-dimensional Hubbard model and compared with results of unrestricted Hartree-Fock (HF) calculations. We fin

S. Balaska, W. Ruehl

We transform the two-matrix model, studied by P.Di Francesco and al., into a normal one-matrix model by identifying a ``formal&#39;&#39; integral used by these authors as a proper integral. We show also, using their method, that the results obtained for the resolvent and the density are not reliable.

Jean-Philippe Bouchaud, Michael Cates

Recent experiments show that an avalanche initiated from a point source propagates downwards by invading a triangular shaped region. The opening angle of this triangle appears to reach 180$^o$ for a critical inclination of the pile, beyond which avalanches also propage upwards. We propose a simple interpretation of these observations, based on an extension o

Yue Yu

We report a systematic improvement to calculate the conductivity which associates to the anomaly of the propagation of surface acoustic waves at $ν={1/2}$ above a two-dimensional electron gas. We try to resolve the discrepancy between theoretical and experimental values for the magnitude of $σ_{xx}(q)$ by considering the contribution to the response function

I. V. Tokatly

The $ν$-component two-dimensional (2D) Bose liquid is considered. It is shown that the finite temperature phase transition exists in this 2D continuously degenerate multicomponent system. The new type of quasi-long-range order occurs as a result of this transition. The correlation function in ordered state is a product of the power-law XY-universality class

J. Abad, M. Ríos

The associated Hamiltonian for a su(3) spin chain combining ${3}$ and ${3^{*}}$ representations is calculated. The ansatz equations for this chain are obtained and solved in the thermodynamic limit, and the ground state and excitations are described. Thus, relations between the number of roots and the number of holes in each level have been found . The excit

C. J. Olson, C. Reichhardt, Franco Nori

We analyze the microscopic dynamics of vortex motion through channels that form river-like fractal networks in a variety of superconducting samples, and relate it to macroscopic measurable quantities such as the power spectrum. As a function of pinning strength, we calculate the fractal dimension, tortuosity, and the corresponding voltage noise spectrum. Abo

Ofer Malcai, Daniel A. Lidar, Ofer Biham, David Avnir

Fractal structures appear in a vast range of physical systems. A literature survey including all experimental papers on fractals which appeared in the six Physical Review journals (A-E and Letters) during the 1990&#39;s shows that experimental reports of fractal behavior are typically based on a scaling range $Δ$ which spans only 0.5 - 2 decades. This range

K. Kowalski, J. Rembielinski

In our previous paper: K. Kowalski and J. Rembieliński, Groups and nonlinear dynamical systems. Dynamics on the SU(2) group, Physica D 99, 237 (1996), we introduced an abstract Newton-like equation on a general Lie algebra such that submanifolds fixed by the second-order Casimir operator are attracting set. The corresponding group parameters satisfy the nonl

K. Kowalski, J. Rembielinski

An abstract Newton-like equation on a general Lie algebra is introduced such that orbits of the Lie-group action are attracting set. This equation generates the nonlinear dynamical system satisfied by the group parameters having an attractor coinciding with the orbit. The periodic solutions of the abstract equation on a Lie algebra are discussed. The particu

P. Ruiz-Lapuente, R. Canal

Determination of the rates at which supernovae of Type Ia (SNe Ia) occur in the early Universe can give signatures of the time spent by the binary progenitor systems to reach explosion and of the geometry of the Universe. Observations made within the Supernova Cosmology Project are already providing the first numbers. Here it is shown that, for any assumed S

M. Coleman Miller, Frederick K. Lamb, Dimitrios Psaltis

The frequencies of the highest-frequency kilohertz QPOs recently discovered in some sixteen neutron stars in low-mass X-ray binary systems are most likely the orbital frequencies of gas in Keplerian orbit around these neutron stars. If so, these QPOs provide tight upper bounds on the masses and radii of these neutron stars and important new constraints on th

Daniel E. Reichart

GRB 971214 is the third gamma ray burst for which an optical afterglow has been detected. I show that the spectrum of this afterglow (optical and X-ray) is inconsistent with the relativistic blast-wave model unless a significant source of extinction is introduced. Assuming that a single absorber exists at redshift z, I find that its V-band absorption magnitu

D. Fisher, D. Fabricant, M. Franx, P. van Dokkum

We present a spectroscopic survey of the rich, X-ray selected, galaxy cluster CL 1358+6245 at z=0.328. When our 173 new multi-slit spectra of cluster galaxies are combined with data from the literature, we produce a catalog of 232 cluster members in a region 10&#39;x11&#39; (3.5 Mpc x 3.8 Mpc) surrounding the brightest cluster galaxy. These data are used to

Fred Hamann

This paper discusses the detection of P V 1118,1128 and other broad absorption lines (BALs) in archival HST spectra of the low-redshift BALQSO, PG 1254+047. The P V identification is secured by excellent redshift and profile coincidences with the other BALs, such as C IV 1548,1550 and Si IV 1393,1403, and by photoionization calculations showing that other li

J. H. Krolik

A critical review is presented of the current status of our understanding of the the spectral output of thermally-radiating accretion disks around black holes, with special attention to those around supermassive black holes in active galactic nuclei. Uncertainties in disk physics (e.g. the nature of the inter-ring stresses, the distribution of dissipation wi

Leen Decin, Hans Van Winckel, Christoffel Waelkens, Eric J. Bakker

We present a detailed chemical analysis on the basis of high-resolution, high signal-to-noise optical spectra of two post-AGB objects IRAS 22223+4327 and IRAS 04296+3429. Both display the unidentified $21 μm$ feature in their IR-spectra. The spectroscopic indicators provide accurate atmospheric parameters of $T_{eff}$=6500 K, $log g=1.0$ and $ξ_t = 5.5 km/s$

G. P. Szokoly, M. U. Subbarao, A. J. Connolly, B. Mobasher

This study presents a wide-field near-infrared (K-band) survey in two fields; SA 68 and Lynx 2. The survey covers an area of 0.6 deg.$^2$, complete to K=16.5. A total of 867 galaxies are detected in this survey of which 175 have available redshifts. The near-infrared number counts to K=16.5 mag. are estimated from the complete photometric survey and are foun

F. Bradamante, F. Matteucci, A. D&#39;Ercole

A chemical evolution model following the evolution of the abundances of H, He, C, N, O and Fe for dwarf irregular and blue compact galaxies is presented. This model takes into account detailed nucleosynthesis and computes in detail the rates of supernovae of type II and I. The star formation is assumed to have proceeded in short but intense bursts. The novel

S. Mariani, M. Cappi, M. Persic, L. Bassani

Preliminary results obtained from BeppoSAX observation of the starburst galaxy NGC253 are presented. X-ray emission from the object is clearly extended but most of the emission is concentrated on the optical nucleus. Preliminary analysis of the LECS and MECS data obtained using the central 4&#39; region indicates that the continuum is well fitted by two ther

A. Franceschini, S. Vercellone, A. C. Fabian

Using recently published estimates - based on high spatial resolution spectroscopy - of the mass M_{BH} of nuclear black holes for a sample of nearby galaxies, we explore the dependence of galaxy nucleus emissivity at various wavelengths on M_{BH}. We confirm an almost linear scaling of the black hole mass with the baryonic mass of the host spheroidal galaxy

Lev Yungelson, Simon F. Portegies Zwart

We discuss the formation and evolution of binaries which contain neutron stars or black holes. It is shown that in a stellar system which for $10^{10}$ yr had star formation rate similar to the current one in the Galactic disc, the rate of neutron star mergers is $\sim 2 \times 10^{-5} yr{-1}$, consistent with the observational estimates. The rate of black h

F. De Paolis, G. Ingrosso, Ph. Jetzer, M. Roncadelli

The discovery of Massive Astrophysical Compact Halo Objects (MACHOs) in microlensing experiments makes it compelling to understand their physical nature, as well as their formation mechanism. Within the present uncertainties, brown dwarfs are a viable candidate for MACHOs, and the present paper deals with this option. According to a recently proposed scenari

Cesario Lia, Giovanni Carraro, Cesare Chiosi, Marco Voli

In this report we describe a parallel implementation of a Tree-SPH code realized using the SHMEM libraries in the Cray T3E supercomputer at CINECA. We show the result of a 3D test to check the code performances against its scalar version. Finally we compare the load balancing and scalability of the code with PTreeSPH (Davé et al 1997), the only other paralle

Christopher W. Churchill, Vincent Le Brun

We report the discovery of two iron-group enhanced high-metallicity Mg II absorbers in a search through 28 Lyman Alpha forest clouds along the PKS 0454+039 sight line. Based upon our survey and the measured redshift number densities of W_r(MgII) <= 0.3 A absorbers and Lyman Alpha absorbers at z ~ 1, we suggest that roughly 5% of Lyman Alpha absorbers at z <

Eric V. Linder

Cosmologies that match in a volume averaged sense need not generally have the same light propagation behaviors. In particular a universe with inhomogeneity may not demonstrate the Friedmann-Robertson-Walker distance-redshift relation even after volume averaging to FRW spacetime. Even the Dyer-Roeder prescription for incorporating inhomogeneity within a unive

George F. Smoot

This document provides a brief summary estimate of Galactic free-free emission and H-alpha emission and their relationship. Particular emphasis is placed on estimating the potential free-free emission in the region of significant confusion for CMB anisotropy measurements. Existing x-ray, ultraviolet and H$α$ emission provide limits on the radio free-free emi

A. J. Barger, A. Aragon-Salamanca, I. Smail, R. S. Ellis

We investigate various probes of luminosity evolution in the rich cluster environment, concentrating in particular on the spheroidal (E/S0) galaxies, using a newly-constructed catalog of morphologically-classified Hubble Space Telescope images of galaxies observed in the cores of 13 clusters with redshifts 0.17<z<0.56. An important distinction of this study

F F Ferreira, J F Fontanari

Given a sequence of $N$ positive real numbers $\{a_1,a_2,..., a_N \}$, the number partitioning problem consists of partitioning them into two sets such that the absolute value of the difference of the sums of $a_j$ over the two sets is minimized. In the case that the $a_j$&#39;s are statistically independent random variables uniformly distributed in the unit

Brett E. Taylor, Chris M. Chambers, William A. Hiscock

We study the evolution of an evaporating rotating black hole, described by the Kerr metric, which is emitting either solely massless scalar particles or a mixture of massless scalar and nonzero spin particles. Allowing the hole to radiate scalar particles increases the mass loss rate and decreases the angular momentum loss rate relative to a black hole which

William Jockusch, James Propp, Peter Shor

In this article we study domino tilings of a family of finite regions called Aztec diamonds. Every such tiling determines a partition of the Aztec diamond into five sub-regions; in the four outer sub-regions, every tile lines up with nearby tiles, while in the fifth, central sub-region, differently-oriented tiles co-exist side by side. We show that when n is

H. R. Christiansen, J. Magnin

We analyze the non-perturbative structure of the strange sea of the nucleon within a meson cloud picture. In a low $Q^2$ approach in which the nucleon is viewed as a three valon bound state, we evaluate the probability distribution of an in-nucleon Kaon-Hyperon pair in terms of splitting functions and recombination. The resulting kaon and hyperon probability

H. Itoyama, A. Tokura

We discuss theoretical implications of the large k USp(2k) matrix model in zero dimension. The model appears as the matrix model of type IIB superstrings on a large $T^{6}/Z^{2}$ orientifold via the matrix twist operation. In the small volume limit, the model behaves four dimensional and its T dual is six-dimensional worldvolume theory of type I superstrings

CLEO Collaboration, B. Behrens et al

In a sample of 6.6 million produced B mesons we have observed decays B -> eta&#39; K, with branching fractions BR(B+ -> eta&#39; K+ = 6.5 +1.5 -1.4 +- 0.9) x $10^{-5}$ and BR(B0 -> eta&#39; K0 = 4.7 +2.7 -2.0 +- 0.9) x $10^{-5}$. We have searched with comparable sensitivity for 17 related decays to final states containing an eta or eta&#39; meson accompanied

Paulo Aguiar, Paulo Crawford

Following recent considerations of a non-zero value for the vacuum energy density and the realization that a simple Kantowski-Sachs model might fit the classical tests of cosmology, we study the qualitative behavior of three anisotropic and homogeneous models: Kantowski-Sachs, Bianchi I and Bianchi III universes, with dust and cosmological constant, in order

Klaus Behrndt, Gabriel Lopes Cardoso, Bernard de Wit, Dieter Lüst

Based on special geometry, we consider corrections to N=2 extremal black-hole solutions and their entropies originating from higher-order derivative terms in N=2 supergravity. These corrections are described by a holomorphic function, and the higher-order black-hole solutions can be expressed in terms of symplectic Sp(2$n$+2) vectors. We apply the formalism

H. J. de Vega, N. Sánchez, F. Combes

We develop a field theoretical approach to the cold interstellar medium (ISM) and large structure of the universe. We show that a non-relativistic self- gravitating gas in thermal equilibrium with variable number of atoms or fragments is exactly equivalent to a field theory of a scalar field phi(x) with exponential self-interaction. We analyze this field the

Tatsuya Ueno

The general solution of a 7D analogue of the 3D Euler top equation is shown to be given by an integration over a Riemann surface with genus 9. The 7D model is derived from the 8D $Spin(7)$ invariant self-dual Yang-Mills equation depending only upon one variable and is regarded as a model describing self-dual membrane instantons. Several integrable reductions

M. N. Chernodub, F. V. Gubarev, M. I. Polikarpov

Correlations of the topological charge Q, the electric current J^e and the magnetic current J^m in SU(2) lattice gauge theory in the Maximal Abelian projection are investigated. It occurs that the correlator <<QJ^e J^m>> is nonzero for a wide range of values of the bare charge. It is shown that: (i) the abelian monopoles in the Maximal Abelian projection are

Yu. A. Firsov, V. V. Kabanov, E. K. Kudinov, A. S. Alexandrov

We show that the conclusion on the breakdown of the standard small polaron theory made recently by E.V. deMello and J. Ranninger (Phys. Rev. B 55, 14872 (1997)) is a result of an incorrect interpretation of the electronic and vibronic energy levels of the two-site Holstein model. The small polaron theory, when properly applied, agrees well with the numerical

S. Fajfer, S. Prelovsek, P. Singer

Using the factorization scheme for the nonleptonic $D \to V V_0$ weak amplitudes, we classify all diagrams which arise in $D \to V γ$ decays and calculate them with the help of the hybrid model which combines the heavy quark effective theory and the chiral Lagrangian approach. Thus we determine the long distance contribution to the amplitudes of Cabibbo allo

K. Takenaga

Effects of boundary conditions of fields for compactified space directions on the supersymmetric gauge theories are discussed. For general and possible boundary conditions the supersymmetry is explicitly broken to yield universal soft supersymmetry breaking terms, and the gauge symmetry of the theory can also be broken through the dynamics of non-integrable

Bo-Yu Hou, Liu Zhao, Xiang-Mao Ding

Elliptic current algebras E_{q,p}(\hat{g}) for arbitrary simply laced finite dimensional Lie algebra g are defined and their co-algebraic structures are studied. It is shown that under the Drinfeld like comultiplications, the algebra E_{q,p}(\hat{g}) is not co-closed for any g. However putting the algebras E_{q,p}(\hat{g}) with different deformation paramete

Haisong Yang

We consider the entropy of near extremal black holes with multiple charges in the context of the recently proposed correspondence principle of Horowitz and Polchinski, including black holes with two, three and four Ramond-Ramond charges. We find that at the matching point the black hole entropy can be accounted for by massless open strings ending on the D-br

Nemanja Kaloper, Andrei Linde, Raphael Bousso

We show that in a generic case of the pre-big-bang scenario, inflation will solve cosmological problems only if the universe at the onset of inflation is extremely large and homogeneous from the very beginning. The size of a homogeneous part of the universe at the beginning of the stage of pre-big-bang (PBB) inflation must be greater than $10^{19}$ $l_s$, wh

Manoelito M. de Souza, Robson N. Silveira

We develop the General Theory of Relativity in a formalism with extended causality that describes physical interaction through discrete, transversal and localized pointlike fields. The homogeneous field equations are then solved for a finite, singularity-free, point-like field that we associate to a ``classical graviton&#34;. The standard Einstein&#39;s cont

Barak Kol, J. Rahmfeld

We study the BPS spectrum of supersymmetric 5 dimensional field theories and their representations as string webs. It is found that a state of given charges exists when it has a representation as an irreducible string web. Its spin is determined by the string web. The number of fermionic zero modes is 8g+4b, where g is the number of internal faces and b is t

R. M. Kashaev, I. G. Korepanov, S. M. Sergeev

We describe a scheme of constructing classical integrable models in 2+1-dimensional discrete space-time, based on the functional tetrahedron equation - equation that makes manifest the symmetries of a model in local form. We construct a very general &#34;block-matrix model&#34; together with its algebro-geometric solutions, study its various particular cases

S. E. Hamann, D. L. Haycock, G. Klose, P. H. Pax

We trap neutral Cs atoms in a two-dimensional optical lattice and cool them close to the zero-point of motion by resolved-sideband Raman cooling. Sideband cooling occurs via transitions between the vibrational manifolds associated with a pair of magnetic sublevels and the required Raman coupling is provided by the lattice potential itself. We obtain mean vib

Anna Sanpera, Rolf Tarrach, Guifre Vidal

We show how to decompose any density matrix of the simplest binary composite systems, whether separable or not, in terms of only product vectors. We determine for all cases the minimal number of product vectors needed for such a decomposition. Separable states correspond to mixing from one to four pure product states. Inseparable states can be described as p

I. H. Deutsch, P. S. Jessen

We study the means to prepare and coherently manipulate atomic wave packets in optical lattices, with particular emphasis on alkali atoms in the far-detuned limit. We derive a general, basis independent expression for the lattice operator, and show that its off-diagonal elements can be tailored to couple the vibrational manifolds of separate magnetic subleve

W. E. Ormand

The effects of isospin-symmetry breaking on the observables for parity-violating electron scattering are investigated within the framework of the nuclear shell model for 12C, 16O, and 28Si. Contributions due to mixing with low-lying states as well as admixtures of 1p-1h configurations (via the radial wave functions) are accounted for. It is found that isospi

H. Witala, W. Gloeckle, D. Hueber, J. Golak

Neutron-deuteron elastic scattering cross sections are calculated at different energies using modern nucleon-nucleon interactions and the Tucson-Melbourne three-nucleon force adjusted to the triton binding energy. Predictions based on NN forces only underestimate nucleon-deuteron data in the minima at higher energies starting around 60 MeV. Adding the three-

Anthony J. Baltz, Chellis Chasman, Sebastian N. White

Detection in zero degree calorimeters of the correlated forward-backward Coulomb or nuclear dissociation of two colliding nuclei is presented as a practical luminosity monitor in heavy ion colliders. Complementary predictions are given for total correlated Coulomb plus nuclear dissociation and for correlated forward-backward single neutrons from the giant di

Michael Christ

To any finite collection of smooth real vector fields $X_j$ in $\reals^n$ we associate a metric in the phase space $T^*\reals^n$. The relation between the asymptotic behavior of this metric and hypoellipticity of $\sum X_j^2$, in the smooth, real analytic, and Gevrey categories, is explored.

Hong-Ming Yin

We study the Cauchy problem for an $p$-Laplacian type of evolution system ${\mathbf H}_{t}+\g [ | \g {\mathbf H}|^{p-2} \g {\mathbf H}|]={\mathbf F}$. This system governs the evolution of a magnetic field ${\bf H}$, where the current displacement is neglected and the electrical resistivity is assumed to be some power of the current density. The existence, un

Siegfried Echterhoff, John Quigg

Using the close relationship between coactions of discrete groups and Fell bundles, we introduce a procedure for inducing a C*-coaction of a quotient group G/N of a discrete group G to a C*-coaction of G itself on an induced C*-algebra. We show that induced coactions behave in many respects similarly to induced actions. In particular, as an analogue of the w

James Propp

This survey article describes a method for choosing uniformly at random from any finite set whose objects can be viewed as constituting a distributive lattice. The method is based on ideas of the author and David Wilson for using ``coupling from the past&#39;&#39; to remove initialization bias from Monte Carlo randomization. The article describes several app

Igor B. Frenkel, Feodor Malikov

We use Kazhdan-Lusztig tensoring to, first, describe annihilating ideals of highest weight modules over an affine Lie algebra in terms of the corresponding VOA and, second, to classify tilting functors, an affine analogue of projective functors known in the case of a simple Lie algebra. For the sake of completeness, the classification of annihilating ideals

William P. Thurston

This is the third in a series of papers constructing hyperbolic structures on all Haken three-manifolds. This portion deals with the mixed case of the deformation space for manifolds with incompressible boundary that are not acylindrical, but are more complicated than interval bundles over surfaces. This is a slight revision of a 1986 preprint, with a few fi

L. N. Granda

The effective potential in the model introduced by Buchbinder-Inagaki-Odintsov (BIO) which represents SUSY NJL model non-minimally coupled with the external gravitational field is found. The topology of the space is considered to be non-trivial. Chiral symmetry breaking under the action of external curvature and non-trivial topology is investigated.

Ichiro Oda

Starting from the Schild action for membrane, we present an alternative formulation of Matrix Theory. First of all, we construct the Schild action for general bosonic p-brane which is classically equivalent to the Nambu-Goto action for p-brane. Next, based on the constraint obtained from the variational equation for the auxiliary field in the case of $p = 2$

Chaouki Boulahouache, George Thompson

We calculate some one loop corrections to the effective action of theories in $d$ dimensions that arise on the dimensional reduction of a Weyl fermion in $D$ dimensions. The terms that we are interested in are of a topological nature. Special attention is given to the effective actions of the super Yang Mills theories that arise on dimensional reduction of t

A. Achucarro, M. de Roo, L. Huiszoon

Recently, a geometric model for the confinement of magnetic charges in the context of type II string compactifications was constructed by Greene, Morrison and Vafa. This model assumes the existence of stable magnetic vortices with quantized flux in the low energy theory. However, quantization of flux alone does not imply that the vortex is stable, since the

M. T. Grisaru, M. Massar, A. Sevrin, J. Troost

The off-shell description of N=(2,2) supersymmetric non-linear sigma-models is reviewed. The conditions for ultra-violet finiteness are derived and T-duality is discussed in detail.

A. V. Smilga

We consider N=1 supersymmetric QCD based on the G_2 gauge group and including 3 chiral matter 7-plets. In that case, the gauge symmetry is broken completely and the instanton-generated superpotential on the classical moduli space is present. If the theory involves the Yukawa term, there are six chirally asymmetric vacua. In the limit when the Yukawa coupling

R. Vilela Mendes

Phenomenological evidence and analytic approximations to the QCD ground state suggest a complex gluon condensate structure. Exclusion of elementary fermion excitations by the generation of infinite mass corrections is a consequence. In addition the existence of vacuum condensates in unbroken non-abelian gauge theories, endows SU(3) and higher order groups wi

Harm Jan Boonstra, Bas Peeters, Kostas Skenderis

We consider a series of duality transformations that leads to a constant shift in the harmonic functions appearing in the description of a configuration of branes. This way, for several intersections of branes, we can relate the original brane configuration which is asymptotically flat to a geometry which is locally isometric to adS_k x E^l x S^m. These resu

M. J. Duff, James T. Liu, J. Rahmfeld

Dirichlet 0-branes, considered as extreme Type IIA black holes with spin carried by fermionic hair, are shown to have the anomalous gyromagnetic ratio g=1, consistent with their interpretation as Kaluza-Klein modes.

S. J. Brodsky

The advent of a next linear $e^\pm e^-$ collider and back-scatterd laser beams will allow the study of a vast array of high energy processes of the Standard Model through the fusion of real and virtual photons and other gauge bosons. As examples, I discuss virtual photon scattering $γ^* γ^* \to X$ in the region dominated by BFKL hard Pomeron exchange and rep

Valeri V. Dvoeglazov

We continue to study the `fermion -- 4-vector potential&#39; interactions in the framework of the McLennan-Case construct which is a reformulation of the Majorana theory of the neutrino. This theory is shown after applying Majorana-like anzatzen to give rise to appearance of unusual terms as \vecσ\cdot [\vec A \times \vec A^\ast ], which were recently discus

Ola Tornkvist

I review some of the mechanisms through which primordial magnetic fields may be created in the electroweak phase transition. I show that no magnetic fields are produced initially from two-bubble collisions in a first-order transition. The initial field produced in a three-bubble collision is computed. The evolution of fields at later times is discussed.

B. Abbott, I. A. Bertram, M. Bhattacharjee, G. Di Loreto

Uncertainties in the NLO calculation of the inclusive jet cross section due to the choice of renormalization scale, parton distribution functions and clustering algorithm are explored. These are found to be similar in size to the current experimental uncertainties of the measured inclusive jet cross section at DZero and CDF.

M. Suzuki

To understand the short-distance vs long-distance final-state interactions, we have performed a detailed amplitude analysis for the two-body decay, J/psi into vector and pseudoscalar mesons. The current data favor a large relative phase nearly 90 degrees between the three-gluon and one-photon decay amplitudes. The source of this phase is apparently in the lo

Jan Stern

Considering QCD in an Euclidean box, the mechanism of spontaneous breaking of chiral symmetry (SB$χ$S) is analyzed in terms of average properties of lowest eigenstates of the Dirac operator. A formal analogy between the pion decay constant and conductivity in disordered systems is established. It follows that SB$χ$S results from a subtle balance between the

V. Barone, T. Calarco, A. Drago

We compute the gluon polarization $ΔG$ and the gluon total angular momentum $J_g$ in the Isgur-Karl quark model. Taking into account self-interaction contributions, we obtain for both quantities a positive value of about 0.24 at the model scale $μ_0^2 \simeq 0.25$ GeV$^2$. This estimate is reasonably close to the expectation from polarized deep inelastic sca

Kiwoon Choi, Eung Jin Chun, Hang Bae Kim

In string/M-theory with a large compactification radius, some axion-like moduli can be much lighter than the gravitino. Generic moduli in gauge-mediated supersymmetry breaking models also have a mass far below the weak scale. Motivated by these, we examine the cosmological implications of light moduli for the mass range from the weak scale to an extremely sm