January 1998 arXiv papers — page 12

M. A. Braun

In the framework of the hard pomeron model it is shown that at large $Q^2$ the diffractive contribution to the structure functions rises as $Q^{0.3362}$ and much slowlier than the total contribution rising as $Q$.

M. A. Braun

In the hard pomeron model consequences are studied which follow from the recently obtained form of the diffractive amplitude for the double scattering on the nucleus and the related EMC effect at small $x$. It is shown that at large $Q^2$ the double scattering contribution to the latter falls as $Q^{-0.6338}$ and in all probability dominates the total effect

T. Teshima, T. Sakai, O. Inagaki

We analyzed the solar, terrestrial and atmospheric neutrinos experiments using the three-flavor neutrino framework and got the allowed regions for parameters (Δm_{12}^2, \sin^22θ_{12}, Δm_{23}^2, θ_{13}, θ_{23}). In solar neutrino experiments, we got the large angle solution (Δm_{12}^2, \sin^22θ_{12})=(4x10^{-6} - 7x10^{-5}eV^2, 0.6 - 0.9) and small angle so

B. L. G. Bakker, M. N. Chernodub, F. V. Gubarev, M. I. Polikarpov

We discuss some properties of abelian monopoles in the Maximal Abelian projection of the SU(2) lattice gluodynamics. We show that in the maximal abelian projection abelian monopoles carry fluctuating electric charge and that the monopole currents are correlated with the magnetic and the electric parts of the SU(2) action density.

Murray A. Moinester, Victor Steiner

We describe a hadron physics program attainable with a partially instrumented CERN COMPASS spectrometer, involving tracking detectors and moderate-size ECAL2/HCAL2 calorimeters. COMPASS can realize a state-of-the-art hadron beam physics program based on hadron polarizability, hybrid mesons, chiral anomaly, and meson radiative transition studies. We review he

S. Massar, R. Parentani

We show that a surface term should be added to the Einstein-Hilbert action in order to properly describe quantum transitions occurring around a black hole. The introduction of this boundary term has been advocated by Teitelboim and collaborators and it has been used in the computation of the black hole entropy. Here, we use it to compute the gravitational co

V. R. Gavrilov, V. N. Melnikov

The D-dimensional cosmological model on the manifold $M = R \times M_{1} \times M_{2}$ describing the evolution of 2 Einsteinian factor spaces, $M_1$ and $M_2$, in the presence of multicomponent perfect fluid source is considered. The barotropic equation of state for mass-energy densities and the pressures of the components is assumed in each space. When the

V. D. Ivashchuk, V. N. Melnikov

A short review of recent results of authors on sigma-model approach in multidimensional gravity with p-branes is presented.

U. Guenther, S. Kriskiv, A. Zhuk

Multidimensional cosmological models with a higher dimensional space-time manifold are investigated under dimensional reduction. In the Einstein conformal frame, the effective potential for the internal scale factors is obtained. The stable compactification of the internal spaces is achieved due to the Casimir effect. In the case of more than one internal sp

J. Paaske, D. V. Khveshchenko

The temperature dependences of the galvanomagnetic and thermoelectric transport coefficients within a generic hot-spot model are reconsidered. Despite the recent success in explaining ac Hall effect data in YBa_{2}Cu_{3}O_{7}, a general feature of this model is a departure from the approximately universal temperature dependences observed for normal state tra

Alex Hansen, Mogens H. Jensen, Kim Sneppen, Giovanni Zocchi

We argue that the first order folding transitions of proteins observed at physiological chemical conditions end in a critical point for a given temperature and chemical potential of the surrounding water. We investigate this critical point using a hierarchical Hamiltonian and determine its universality class. This class differs qualitatively from those of ot

A. Vazquez, O. Sotolongo-Costa

Glass-like materials are nonequilibrium systems where the relaxation time may exceed reasonable time scales of observations. In the present paper a dynamic percolation model is introduced in order to explain the principal properties of glass-like materials near the dynamic transition. Here, contrary to conventional percolation problems, clusters are groups o

Fabian H. L. Essler, Vladimir E. Korepin, Franck T. Latremoliere

We consider finite temperature dynamical correlation functions in the interacting delta-function Bose gas. In the low-temperature limit the asymptotic behaviour of correlation functions can be determined from conformal field theory. In the present work we determine the deviations from conformal behaviour at low temperatures.

T. Alarcon, A. Perez-Madrid, J. M. Rubi

We propose a new mechanism to increase the reactions ratesin multistable autocatalytic systems. The mechanism is based upon the possibility for the enhancement of the response of the system due to the cooperative behavior between the noise and an external periodic modulation. In order to illustrate this feature we compute the reaction velocities for the part

T. Alarcon, A. Perez-Madrid, J. M. Rubi

We propose a method to analytically show the possibility for the appearance of a maximum in the signal-to-noise ratio in nonpotential systems. We apply our results to the FitzHugh-Nagumo model under a periodic external forcing, showing that the model exhibits stochastic resonance. The procedure that we follow is based on the reduction to a one-dimensional dy

Igor Tsatskis

It is shown how to derive simple polynomial expressions for the variational configurational entropy starting from the cluster variation method (CVM). As an example, first six terms of the expansion of the entropy in powers of the nearest-neighbour (NN) short-range order (SRO) parameter are obtained for the NN Ising ferromagnet on the face-centered cubic latt

Chihara, Kahl

We have applied the quantal hypernetted-chain equations in combination with the Rosenfeld bridge-functional to calculate the atomic and the electronic structure of compressed liquid-rubidium under high pressure (0.2, 2.5, 3.9, and 6.1 GPa); the calculated structure factors are in good agreement with experimental results measured by Tsuji et al. along the mel

D. M. Jezek, M. Pi, M. Barranco, R. J. Lombard

The effect of ring vortices on the destabilization of supersaturated liquid helium mixtures at very low temperatures is investigated as a function of pressure. We have found that large ring vortices trigger the segregation of 3He at smaller values of the concentration than small ring vortices. Our calculations indicate that the existence of ring vortices in

Ar. Abanov, V. L. Pokrovsky

Skyrmions are the magnetic defects in an ultrathin magnetic film, similar to the bubble domains in the thicker films. Even weak uniaxial anisotropy determines its radius unambiguously. We consider the dynamics of the skyrmion decay. We show that the discreteness of the lattice in an isotropic 2D magnet leads to a slow rotation of the local magnetization in t

Yuli Lyanda-Geller, I. L. Aleiner, Paul M. Goldbart

Quantum interference phenomena in the conductivity of mesoscopic ferromagnets are considered, particularly with regard to the effects of geometric phases acquired by electrons propagating through regions of spatially varying magnetization (due, e.g., to magnetic domain walls). Weak localization and electron-electron interaction quantum corrections to the con

Steven C. van der Marck

The site percolation problem is studied on d-dimensional generalisations of the Kagome' lattice. These lattices are isotropic and have the same coordination number q as the hyper-cubic lattices in d dimensions, namely q=2d. The site percolation thresholds are calculated numerically for d= 3, 4, 5, and 6. The scaling of these thresholds as a function of d

Darryl D. Holm, Vladimir Zeitlin

We show that the equation of quasigeostrophic (QG) potential vorticity conservation in geophysical fluid dynamics follows from Hamilton's principle for stationary variations of an action for geodesic motion in the f-plane case or its prolongation in the beta-plane case. This implies a new momentum equation and an associated Kelvin circulation theorem for

O. V. Usatenko, J. -P. Provost, G. Vallee, A. Boudine

In this paper we study to what extent the canonical equivalence and the identity of the geometric phases of dissipative and conservative linear oscillators, established in a preceeding paper, can be generalized to nonlinear ones. Considering first the 1-D quartic generalized oscillator we determine, by means of a perturbative time dependent technic of reduct

H. Cendra, D. D. Holm, M. J. W. Hoyle, J. E. Marsden

Low's well known action principle for the Maxwell-Vlasov equations of ideal plasma dynamics was originally expressed in terms of a mixture of Eulerian and Lagrangian variables. By imposing suitable constraints on the variations and analyzing invariance properties of the Lagrangian, as one does for the Euler equations for the rigid body and ideal fluids,

D. D. Holm, J. E. Marsden, T. S. Ratiu

We study Euler-Poincare systems (i.e., the Lagrangian analogue of Lie-Poisson Hamiltonian systems) defined on semidirect product Lie algebras. We first give a derivation of the Euler-Poincare equations for a parameter dependent Lagrangian by using a variational principle of Lagrange d'Alembert type. Then we derive an abstract Kelvin-Noether theorem for t

Stacy McGaugh, Erwin de Blok

The severity of the mass discrepancy in spiral galaxies is strongly correlated with the central surface brightness of the disk. Progressively lower surface brightness galaxies have ever larger mass discrepancies. No other parameter (luminosity, size, velocity, morphology) is so well correlated with the magnitude of the mass deficit. The rotation curves of lo

W. Tucker, P. Blanco, S. Rappoport, L. David

We identify the extended Einstein IPC X-ray source, 1E0657-56, with a previously unknown cluster of galaxies at a redshift of $z=0.296$. Optical CCD images show the presence of a gravitational arc in this cluster and galaxy spectra yield a cluster velocity dispersion of $1213^{+352}_{-191}$ km s$^{-1}$. X-ray data obtained with the ROSAT HRI and ASCA indicat

M. Dominik

Though there have been some galactic microlensing events which show a clear signature of a binary lens, no event has yet been claimed as due to lensing of a binary source. Here I argue that this may be due to the fact that most of the binary source events show light curves which can be fitted with the simpler model of a blended single source.

R. B. C. Henry

Galactic and extragalactic abundance studies of H II regions, planetary nebulae, and supernova remnants are compiled and their implications briefly reviewed. Galaxy global metallicity appears to be related directly to total mass and morphology, while gradient slopes are uncorrelated with these parameters, although barred spirals tend to have flatter profiles

P. B. Tissera, R. Dom\ci nguez-Tenreiro

We have carried out a comparative analysis of the properties of dark matter halos in N-body and hydrodynamical simulations. We analyze their density profiles, shapes and kinematical properties with the aim of assessing the effects that hydrodynamical processes might produce on the evolution of the dark matter component. The simulations performed allow us to

James Dunlop

I describe the current status of our attempts to determine the age of the oldest known stellar populations at high redshift, in the red mJy radio galaxies 53W091 ($z = 1.55$) and 53W069 ($z = 1.43$). During the past year the original conclusion of Dunlop et al. (1996) - that 53W091 is $>3$ Gyr old - has been questioned from two, basically orthogonal directio

Richard S Ellis

I review recent observational progress concerning the evolution of the morphological distribution of galaxies in the rich cluster environment and in the faint field population. By coupling HST imagery with ground-based spectroscopic diagnostics, evidence accumulates that galaxy morphology can be a transient phenomenon reflecting various changes in the star f

G. Fiorentini, M. Moretti, F. L. Villante

The anisotropy of the positrons emitted in the reaction $\barν_{e}+p\to n+e^{+}$ has to be taken into account for extracting an antineutrino signal in Superkamiokande. For the Sun, this effect allows a sensitivity to $ν_{e}\to\barν_{e}$ transition probability at the 3% level already with the statistics collected in the first hundred days. For a supernova in

Jacco Vink

We present the results of three observations of shell-type supernova remnants observed by BeppoSAX. Two of the remnants (N132D and Cas A) are oxygen rich supernova remnants. They were observed during the PV phase. SN1006 was observed during A01. For SN1006 we present preliminary results on the abundance measurements based on the emission from the center of t

Saku Tsuneta, Tsuguya Naito

We propose that non-thermal electrons are efficiently accelerated by first-order Fermi process at the fast shock, as a natural consequence of the new magnetohydrodynamic picture of the flaring region revealed with Yohkoh. An oblique fast shock is naturally formed below the reconnection site, and boosts the acceleration to significantly decrease the injection

Sergei A. Levshakov, Wilhelm H. Kegel, Fumio Takahara

The apparent discrepancy between low and high D abundances derived from QSO spectra may be caused by spatial correlations in the stochastic velocity field. If one accounts for such correlations, one finds good agreement between different observations and the theoretical predictions for standard big bang nucleosynthesis (SBBN). In particular, we show that the

Xiangdong Shi

COBE-normalized flat (matter plus cosmological constant) and open Cold Dark Matter (CDM) models are tested by comparing their expected Hubble flow variations and the observed variations in a Type Ia supernova sample and a Tully Fisher cluster sample. The test provides a probe of the CDM power spectrum on scales of $0.02h$ Mpc$^{-1}\la k\la 0.2h$ Mpc$^{-1}$,

Xiangdong Shi, George M. Fuller

We calculate the luminosity and energy spectrum of the neutrino emission from electron-positron pair annihilation during the collapse of a supermassive star (${M} \ga 5\times10^4 {M_\odot}$). We then estimate the cumulative flux and energy spectrum of the resulting neutrino background as a function of the abundance and redshift of supermassive stars and the

Tomonori TOTANI

Most of proposed models of cosmological gamma-ray bursts (GRBs) are associated to gravitational collapses of massive stars, and hence evolution of the GRB rate, which is crucially important in GRB intensity distribution analysis, is determined by the cosmic star formation history. Here we present complementary results of GRB logN-logP analysis, which were om

Tomonori Totani

We present a new strategy for measuring the electron neutrino mass ($\mnue$) by future detection of a Galactic supernova in large underground detectors such as the Super-Kamiokande (SK). This method is nearly model-independent and one can get a mass constraint in a straightforward way from experimental data without specifying any model parameters for profile

Christian Y. Cardall, George M. Fuller

It has recently been suggested that cosmologically significant numbers of black holes could form during a first-order QCD phase transition. Further, it has been asserted that these black holes would have masses corresponding naturally to the inferred mass ($\sim 1 M_{\odot}$) of the MACHOs responsible for the observed gravitational microlensing events. In th

Stacy McGaugh, Erwin de Blok

The rotation curves of low surface brightness galaxies provide a unique data set with which to test alternative theories of gravitation over a large dynamic range in size, mass, surface density, and acceleration. Many clearly fail, including any in which the mass discrepancy appears at a particular length-scale. One hypothesis, MOND [Milgrom 1983, ApJ, 270,

Roberto Soria, Dayal T. Wickramasinghe, Richard W. Hunstead, Kinwah Wu

We report optical spectroscopic observations of the Low Mass X-ray Binary GRO J1655-40 during outbursts in August-September 1994 and in June 1996. The spectra show emission and absorption lines from the accretion disk surrounding the X-ray source, which have enabled us to measure the motion of the black-hole candidate in this system. It is the first time amo

Nadav M. Shnerb, David R. Nelson

The nature of extended states in disordered tight binding models with a constant imaginary vector potential is explored. Such models, relevant to vortex physics in superconductors and to population biology, exhibit a delocalization transition and a band of extended states even for a one dimensional ring. Using an analysis of eigenvalue trajectories in the co

Jan de Boer, Kentaro Hori, Hirosi Ooguri, Yaron Oz

We study dynamical supersymmetry breaking in four dimensions using the fivebrane of M theory, in particular for the Izawa-Yanagida-Intriligator-Thomas (IYIT) model, which we realize as the worldvolume theory of a certain M-theory fivebrane configuration. From the brane point of view, supersymmetry is broken when a holomorphic configuration with the proper bo

A. A. Bytsenko, A. E. Goncalves, S. Nojiri, S. D. Odintsov

We calculate vacuum energy for twisted SUSY D-brane on toroidal background with constant magnetic or constant electric field. Its behaviour for toroidal D-brane (p=2) in constant electric field shows the presence of stable minimum for twisted versions of the theory. That indicates such a background maybe reasonable groundstate.

John C. Collins, Andreas Freund

We show that factorization holds for the deeply virtual Compton scattering amplitude in QCD, up to power suppressed terms, to all orders in perturbation theory. Furthermore, we show that the virtuality of the produced photon does not influence the general theorem.

Gottfried Curio, Ron Y. Donagi

The moduli in a 4D N=1 heterotic compactification on an elliptic CY, as well as in the dual F-theoretic compactification, break into "base" parameters which are even (under the natural involution of the elliptic curves), and "fiber" or twisting parameters; the latter include a continuous part which is odd, as well as a discrete part. We inter

Marco Frasca

Duality is considered for the perturbation theory by deriving, given a series solution in a small parameter, its dual series with the development parameter being the inverse of the other. A dual symmetry in perturbation theory is identified. It is then shown that the dual to the Dyson series in quantum mechanics is given by a recent devised series having the

David Crampton, P. L. Schechter, J. -L. Beuzit

H band observations with a spatial resolution of 0.15" carried out with the Canada-France-Hawaii Telescope adaptive optics system show a galaxy between the components of the double BAL quasar SBS 1520+530, thereby confirming this system as a gravitational lens. The galaxy is located 0.40" from the fainter of the two QSO images and is offset 0.12"

V. M. Tkachuk

A new supersymmetry method for the generation of the quasi-exactly solvable (QES) potentials with two known eigenstates is proposed. Using this method we obtained new QES potentials for which we found in explicit form the energy levels and wave functions of the ground state and first excited state.

G. F. Giudice, R. Rattazzi

Theories with gauge-mediated supersymmetry breaking provide an interesting alternative to the scenario in which the soft terms of the low-energy fields are induced by gravity. These theories allow for a natural suppression of flavour violations in the supersymmetric sector and have very distinctive phenomenological features. Here we review their basic struct

D. Bauer, R. R. E. Salomaa, P. Mulser

A thin and dense plasma layer is created when a sufficiently strong laser pulse impinges on a solid target. The nonlinearity introduced by the time-dependent electron density leads to the generation of harmonics. The pulse duration of the harmonic radiation is related to the risetime of the electron density and thus can be affected by the shape of the incide

J. Sommer-Larsen, S. Gelato, H. Vedel

When only cooling processes are included, smoothed-particle hydrodynamical simulations of galaxy formation in a Cold Dark Matter hierarchical clustering scenario consistently produce collapsed objects that are deficient in angular momentum by a factor of about 25 relative to the disks of observed spiral galaxies. It is widely hoped that proper allowance for

C. Hoeppler, W. Zwerger

In a recent letter Stafford, Baeriswyl and Burki have provided a simple model for the elastic force in metallic constrictions of nanometer size. By employing a semiclassical Weyl expansion for the density of states of transverse modes, we show that for any smooth cross section, there is a universal contribution (4 epsilon_F)/(9 lambda_F) to the average force

A. Ghosh

A one-dimensional gas model has been constructed and shown to provide correct expressions for entropies for extremal and near-extremal BTZ black holes. Recently suggested boosting of black strings is used to compute the entropy for the Schwarzschild black hole also from this gas model.

H. Makino, I. H. Inoue, M. J. Rozenberg, Y. Aiura

Optical conductivity spectra of single crystals of Ca_1-xSr_xVO_3 have been studied to elucidate how the electronic behavior depends on the strength of the electron correlation without changing the nominal number of electrons per vanadium atom. The effective mass deduced by the analysis of the Drude-like contribution do not show critical enhancement, even th

Atsushi Takahashi

We will show that the duality for regular weight systems introduced by K. Saito can be interpreted as the duality for orbifoldized Poincare polynomials.

George Tsoupros

The limitations of three-dimensional semi-classical gravity are explored in the context of a conformally invariant theory for a self-interacting scalar field. The analysis of the theory's scaling behaviour reveals that scalar-loop effects contribute to the conformal anomaly only at advanced orders allowing for a range of relevant energy scales which exte

Takuya Hayashi, Yoshihisa Ohshima, Kiyoshi Okuyama, Hiroshi Suzuki

We formulate a manifestly supersymmetric gauge covariant regularization of supersymmetric chiral gauge theories. In our scheme, the effective action in the superfield background field method above one-loop is always supersymmetric and gauge invariant. The gauge anomaly has a covariant form and can emerge only in one-loop diagrams with all the external lines

Eli Biham, Michel Boyer, Gilles Brassard, Jeroen van de Graaf

Security of quantum key distribution against sophisticated attacks is among the most important issues in quantum information theory. In this work we prove security against a very important class of attacks called collective attacks (under a compatible noise model) which use quantum memories and gates, and which are directed against the final key. Although at

Marek Nowakowski

We analyse the electromagnetic coupling in the Kemmer-Duffin-Petiau (KDP) equation. Since the KDP--equation which describes spin-0 and spin-1 bosons is of Dirac-type, we examine some analogies and differences from the Dirac equation. The main difference to the Dirac equation is that the KDP equation contains redundant components. We will show that as a resul

Valery P. Karassiov

A general algebraic approach, incorporating both invariance groups and dynamic symmetry algebras, is developed to reveal hidden coherent structures (closed complexes and configurations) in quantum many-body physics models due to symmetries of their Hamiltonians $H$. Its general ideas are manifested on some recent new examples: 1) G-invariant bi-photons and a

S. Khoroshkin, D. Lebedev, S. Pakuliak

We investigate different Hopf algebras associated to Yang's solution of quantum Yang-Baxter equation. It is shown that for the precise definition of the algebra one needs the commutation relations for the deformed algebra of formal currents and the specialization of the Riemann problem for the currents. Two different Riemann problems are considered. They

M. Olshanetsky, V. Rogov

We consider functions on the lattice generated by the integer powers of $q^2$ for $0<q<1$ and construct the $q$-analog of Fourier transform based on the Jackson integral in the space of distributions on the lattice.

Sergiu I. Vacaru

Radu Miron&#39;s approach to modelling of generalized Lagrange, Finsler and Kaluza-Klein spaces on vector (super) bundles provided with compatible nonlinear and distinguished connections and metric structures is discussed in connection with the theory of locally anisotropic field interactions and strings.

M. V. Ivanov, P. Schmelcher

The ground and some excited states of the Li atom in external uniform magnetic fields are calculated by means of our 2D mesh Hartree-Fock method for field strengths ranging from zero up to 2.35 10^8 T. With increasing field strength the ground state undergoes two transitions involving three different electronic configurations: for weak fields the ground stat

Urs Achim Wiedemann, Boris Tomasik, Ulrich Heinz

The preliminary CERN SPS NA49 Pb+Pb 158 GeV/A negative one- and two-particle spectra at mid-rapidity are consistent with a source of temperature 130 MeV, lifetime 9 fm/c, transverse flow 0.35, and a transverse geometric size which is twice as large as the cold Pb nucleus.

E. Shuryak, D. Teaney

We suggest that the new regime of $J/ψ$ suppression in Pb-Pb collisions found by the NA50 experiment at CERN is the result of non-trivial space-time evolution due to specific behavior of the Equation of State (EOS) near the QCD phase transition. We also study another suppression channel, the conversion of $J/ψ$ into $η_c$ during the late cool hadronic stage,

M. De Sanctis, E. Santopinto, M. M. Giannini

We perform a calculation of the relativistic corrections to the electromagnetic elastic form factors of the nucleon obtained with various Constituent Quark Models. With respect to the non relativistic calculations a substantial improvement is obtained up to Q^2 about 2 (GeV/c)^2.

H. Sorge

It is shown how to obtain accurate values for American options using Monte Carlo simulation. The main feature of the novel algorithm consists of tracking the boundary between exercise and hold regions via optimization of a certain payoff function. We compare estimates from simulation for some types of claims with results from binomial tree calculations and f

B. M. Brown, M. S. P. Eastham, D. K. R. McCormack

This paper is part of a series of papers in which the asymptotic theory and appropriate symbolic computer code are developed to compute the asymptotic expansion of the solution of an n-th order ordinary differential equation. The paper examines the situation when the matrix that appears in the Levinson expansion has a double eigenvalue. Application is made t

B. M. Brown, M. S. P. Eastham, D. K. R. McCormack

This paper reports on a new algorithm to compute the asymptotic solutions of a linear differential system. A feature of the algorithm is the ability to accommodate periodic coefficients.

Leonid Polterovich

We prove that the group of Hamiltonian diffeomorphisms of the 2-sphere has infinite diameter with respect to Hofer&#39;s metric. Our approach is based on the theory of Lagrangian intersections.

B. M. Brown, M. S. P. Eastham, D. K. R. McCormack, W. D. Evans

This paper reports on recent work to compute the asymptotic solution of a n-th order ordinary differential equation. Symbolic methods are used to compute the asymptotics over a large region. Application is made to the computation of the Titchmarsh-Weyl M-matrix for the fourth order operator.

Malcolm Brown, Leon Greenberg, Marco Marletta

We prove some new results which justify the use of interval truncation as a means of regularising a singular fourth order Sturm-Liouville problem near a singular endpoint. Of particular interest are the results in the so called lim-3 case, which has no analogue in second order singular problems.

B. M. Brown, M. Marletta

For any real limit-$n$ $2n$th-order selfadjoint linear differential expression on $[0,\infty)$, Titchmarsh- Weyl matrices $M(λ)$ can be defined. Two matrices of particu lar interest are the matrices $M_D(λ)$ and $M_N(λ)$ assoc iated respectively with Dirichlet and Neumann boundary conditions at $x=0$. These satisfy $M_D(λ) = -M_{N}(λ)^{-1}$. It is known that

Miao Li, Emil Martinec

Black holes in matrix theory may consist of interacting clusters (correlated domains) which saturate the uncertainty principle. We show that this assumption qualitatively accounts for the thermodynamic properties of both charged and neutral black holes, and reproduces the asymptotic geometry seen by probes.

P. O. Mazur

This is a short account of our work on the statistical mechanics of `cold&#39; quantum black holes in the constituent model of a black hole$^{3,4,6}$. A quantum Schwarzschild black hole consists of gravitational atoms of Planckian mass scale$^{3,4,6}$. The gapless collective excitations of a bound state of N gravitational atoms dominate the thermodynamics of

Malgorzata Bakalarska, Waclaw Tybor

The covariant propagator of the notivarg is found. It has the Feynmann - like form.

Yoonbai Kim, Kyoungtae Kimm

Bogomolnyi-type bound is constructed for the topological solitons in O(3) nonlinear $σ$ model coupled to gravity with a negative cosmological constant. Spacetimes made by self-dual solutions form a class of Gödel-type universe. In the limit of a spinless massive point particle, the obtained stationary metric does not violate the causality and it is a new poi

Andrei Losev, Nikita Nekrasov, Samson Shatashvili

We propose a few tests of Seiberg-Witten solutions of $\mathcal{N}=2$ supersymmetric gauge theories by the instanton calculus in twisted gauge theories. We re-examine the low-energy effective abelian theory in the presence of sources and present the formalism which makes duality transformations transparent and easily fixes all the contact terms in a broad cl

A. H. Hoang

For a proper theoretical description of the top quark pair production cross section at the First Muon Collider in the kinematic regime away from the threshold the complete mass and energy dependence has to be taken into account. Two-loop calculations for the photon mediated total cross section are reviewed.

Yung Su Tsai

We discuss the ways to find CP violation in the decay of $τ^\pm\to ν_τ+ 3π$ from unpolarized as well as polarized $τ^\pm$.

A. H. Hoang

It is shown how nonrelativistic QCD (NRQCD) can be used to determine next-to-next-to-leading order relativistic and short-distance contributions to the total $t\bar t$ production cross section in the threshold regime at lepton colliders. A recipe for the calculation of all such contributions for the total photon mediated production cross section is presented

J. M. Moreno, M. Quiros, M. Seco

We compute the tunneling probability from the symmetric phase to the true vacuum, in the first order electroweak phase transition of the MSSM, and the corresponding Higgs profiles along the bubble wall. We use the resummed two-loop temperature-dependent effective potential, and pay particular attention to the light stop scenario, where the phase transition c

A. Ali

Some selected topics in flavour changing neutral current processes in $B$ decays are discussed in the context of the Standard Model. The emphasis here is on the determination of the CKM matrix elements from the ongoing and forthcoming experiments. The topics discussed include: (i) CKM-allowed radiative decays $B \to X_s + γ$, (ii) CKM-suppressed radiative de

Matthias Neubert

Recent developments in the theory of weak decays of heavy flavours are reviewed. Applications to exclusive semileptonic B decays, the semileptonic branching ratio and charm counting, beauty lifetimes, and hadronic B decays are discussed.

Nikolaos Kidonakis, Gianluca Oderda, George Sterman

We construct dijet differential cross sections at large momentum transfer, in which threshold logarithms have been summed to all orders in perturbation theory. This extends previous work on heavy quark production, by treating collinear singularities associated with hard, massless partons in the final state. The resummed corrections enable us to define, in th

A. D. Dolgov

The comparison of the Standard Cosmological Model (SCM) with astronomical observations, i.e. theory versus experiment, and with the Minimal Standard Model (MSM) in particle physics, i.e. theory versus theory, is discussed. The main issue of this talk is whether cosmology indicates new physics beyond the standard $SU(3)\times SU(2)\times U(1)$ model with mini

Markus H. Thoma

In order to describe properties of an equilibrated quark-gluon plasma, QCD at finite temperature (and density) has to be considered. Besides lattice calculations, which can be applied only to static quantities at zero density, perturbative QCD has been used. At finite temperature, however, serious problems such as infrared divergent and gauge dependent resul

W. Kilian, K. Riesselmann

A heavy Higgs resonance is described in a representation-independent way which is valid for the whole energy range of 2 -> 2 scattering processes, including the asymptotic behavior at low and high energies. The low-energy theorems which follow from to the custodial SU_2 symmetry of the Higgs sector restrict the possible parameterizations of the lineshape tha

G. -j. Ni, S. -y Lou, W. -f Lu, J. -f Yang

Basing on new regularization-renormalization method, the $λϕ^4$ model used in standard model is studied both perturbatively and nonperturbatively (by Gaussian effective potential). The invariant property of two mass scales is stressed and the existence of a (Landau) pole is emphasized. Then after coupling with the SU(2)$\times$U(1) gauge fields, the Higgs ma

R. N. Mohapatra

These lectures begin with a brief introduction to the minimal supersymmetric standard model (MSSM) and the various mechanisms for hidden sector supersymmetry breaking and go on to provide a pedagogical discussion of the various kinds of supersymmetric unified theories beyond the MSSM including SUSY GUTs. Their implications for proton decay, R-parity violatio

A. Hayashigaki, Y. Kanazawa, Yuji Koike

We present a calculation of the two-loop anomalous dimension for the transversity distribution $h_1(x,Q^2)$, $γ^{h(1)}_n$, in the MS scheme of the dimensional regularization. Because of the chiral-odd nature, $h_1$ does not mix with the gluon distributions, and thus our result is the same for the flavor-singlet and nonsinglet distributions. At small $n$ (mom

CLEO Collaboration, C. P. Jessop et al

Using a data sample with integrated luminosity of about 3.9 fb^{-1} collected in e+ e- annihilation with the CLEO-II detector at the Cornell Electron Storage Ring, we have measured the branching ratios for the decay modes Ds -> (eta, eta&#39;) pi and Ds -> (eta, eta&#39;) rho relative to Ds -> phi pi. These decay modes are among the most common hadronic deca

A. Yu. Kamenshchik, I. M. Khalatnikov, A. V. Toporensky

We investigate the cosmological model with the complex scalar self-interacting inflaton field non-minimally coupled to gravity. The different geometries of the Euclidean classically forbidden regions are represented. The instanton solutions of the corresponding Euclidean equations of motion are found by numerical calculations supplemented by the qualitative

Eric Poisson

The accuracy of the post-Newtonian waveforms, both in standard and Pade form, is determined by computing their matched-filtering overlap integral with a reference waveform obtained from black-hole perturbation theory.

V. N. Melnikov

A short review of recent results on exact solutions in multidimensional cosmology and overview of reports at workshop in MG8 (held by the author) are presented.

Uwe Muench, Frank Gronwald, Friedrich W. Hehl

Recently Kaniel & Itin proposed a gravitational model with the wave type equation [\square+λ(x)]\vartheta^α=0 as vacuum field equation, where \vartheta^αdenotes the coframe of spacetime. They found that the viable Yilmaz-Rosen metric is an exact solution of the tracefree part of their field equation. This model belongs to the teleparallelism class of gravita