December 1999 arXiv papers — page 8

Matteo Beccaria

We propose a new Monte Carlo algorithm for the numerical study of general lattice models in Hamiltonian form. The algorithm is based on an initial Ansatz for the ground state wave function depending on a set of free parameters which are dynamically optimized. The method is discussed in details and results are reported from explicit simulations of U(1) lattic

A. O. Parry, C. Rascon, A. J. Wood

We study 2D wedge wetting using a continuum interfacial Hamiltonian model which is solved by transfer-matrix methods. For arbitrary binding potentials, we are able to exactly calculate the wedge free-energy and interface height distribution function and, thus, can completely classify all types of critical behaviour. We show that critical filling is character

Fabrizio Lillo, Rosario N. Mantegna

We introduce power-law tail quantum wave packets. We show that they can be seen as eigenfunctions of a Hamiltonian with a physical potential. We prove that the free evolution of these packets presents an asymptotic decay of the maximum of the wave packets which is anomalous for an interval of the characterizing power-law exponent. We also prove that the numb

Y. Shi

Analytical investigations are made on BML two-dimensional traffic flow model with alternative movement and exclude-volume effect. Several exact results are obtained, including the upper critical density above which there are only jamming configurations asymptotically, and the lower critical density below which there are only moving configurations asymptotica

M. Hagiwara, H. A. Katori, U. Schollwöck, H. -J. Mikeska

Specific heat measurements down to 0.5 K have been performed on a single crystal sample of a spin-ladder like compound Cu$_{2}$(C$_{5}$H$_{12}$N$_{2}$)$_{2}$Cl$_{4}$ under magnetic fields up to 12 T. The temperature dependence of the observed data in a magnetic field below 6 T is well reproduced by numerical results calculated for the S=1/2 two-leg ladder wi

Z. Neda, Z. Dezso

We consider the one-dimensional quantum-statistical problem of interacting spin-less particles in an infinite deep potential valley and on a ring. Several limits for the applicability of the Quantum Monte Carlo (QMC) methods were revealed and discussed. We show the inapplicability of the QMC method for ring-like geometries, realize an unphysical frustration

Charles Reichhardt, Richard T. Scalettar, Gergely T. Zimanyi, Niels Gronbech-Jensen

We examine Shapiro steps for vortex lattices interacting with periodic pinning arrays driven by AC and DC currents. The vortex flow occurs by the motion of the interstitial vortices through the periodic potential generated by the vortices that remain pinned at the pinning sites. Shapiro steps are observed for fields B_ϕ < B < 2.25B_ϕ with the most pronouced

T. Senthil, Matthew P. A. Fisher

Theoretical attempts to explain the origin of high temperature superconductivity are challenged by the complexity of the normal state, which exhibits three regimes with increasing hole doping: a pseudo-gap regime when underdoped, strange power laws near optimal doping and more conventional metallic behavior when heavily overdoped. We suggest that the origin

Erkan Tuzel, Ayse Erzan

A generic model of a random polypeptide chain, with discrete torsional degrees of freedom and Hookean springs connecting pairs of hydrophobic residues, reproduces the energy probability distribution of real proteins over a very large range of energies. We show that this system with harmonic interactions, under dissipative dynamics driven by random noise, lea

Itzhack Dana

An exact renormalization scheme is introduced for quantum Anosov maps (QAMs) on a torus for general boundary conditions (BCs), whose number is always finite. Given a QAM $\hat{U}$ with $k$ BCs and Planck&#39;s constant $\hbar =2π/p$ ($p$ integer), its $n$th renormalization iterate $\hat{U}^{(n)}={\cal R}^{n}(\hat{U})$ is associated with $k$ BCs for all $n$ a

Laszlo Matyas, Tamas Tel, Jurgen Vollmer

A consistent description of simultaneous heat and particle transport, including cross effects, and the associated entropy balance is given in the framework of a deterministic dynamical system. This is achieved by a multibaker map where, besides the phase-space density of the multibaker, a second field with appropriate source terms is included in order to mim

The Milagro Collaboration, R. Atkins

Milagrito, a large, covered water-Cherenkov detector, was the world&#39;s first air-shower-particle detector sensitive to cosmic gamma rays below 1 TeV. It served as a prototype for the Milagro detector and operated from February 1997 to May 1998. This paper gives a description of Milagrito, a summary of the operating experience, and early results that demon

Sergei Nayakshin

We present a simple analytical formula for the Thomson depth of the X-ray heated skin of accretion disks valid at any radius and for a broad range of spectral indices of the incident X-rays, accretion rates and black hole masses. We expect that this formula may find useful applications in studies of geometry of the inner part of accretion flows around compac

Bradley E. Schaefer

The galactic environment of Gamma Ray Bursts can provide good evidence about the nature of the progenitor system, with two old arguments implying that the burst host galaxies are significantly subluminous. New data and new analysis have now reversed this picture: (A) Even though the first two known host galaxies are indeed greatly subluminous, the next eight

B. W. Miller

Massive clusters are now seen to form easily in interacting and merging galaxies, making these excellent environments for studying the properties of young clusters. New observations of the Antennae (NGC 4038/39) show that the most luminous young clusters do not have a measurable tidal radius. Most observations suggest that the luminosity function (LF) and ma

T. M. Kneiske, K. Mannheim

We compute the attenuation of gamma-rays from remote quasars due to interactions with ambient low-energy photons produced by stars in galaxies and show that the next-generation gamma ray telescopes can probe the cosmic star formation rate at high redshifts.

Maria J. Sempere, Jose Cernicharo, Bertrand Lefloch, Eduardo Gonzalez-Alfonso

We report on sensitive far-infrared observations of $^{12}$CO pure rotational transitions in the OMC-1 core of Orion. The lines were observed with the Long Wavelength Spectrometer (LWS) in the grating mode on board the Infrared Space Observatory (ISO), covering the 43-197 $μ$m wavelength range. The transitions from $J_{up}=14$ up to $J_{up}=19$ have been ide

Hisanori Furusawa, Kazuhiro Shimasaku, Mamoru Doi, Sadanori Okamura

We report new improved photometric redshifts of 1048 galaxies in the Hubble Deep Field (HDF). A standard chi^2 minimizing method is applied to seven-color UBVIJHK photometry by Fernandez-Soto, Lanzetta, & Yahil (1999). We use 187 template SEDs representing a wide variety of morphology and age of observed galaxies based on a population synthesis model by Koda

Felix I. Mirabel, Yael Fuchs, and Sylvain Chaty

Infrared observations of the environment of the two Soft Gamma-ray Repeaters (SGRs) with the best known locations on the sky show that they are associated to clusters of massive stars. Observations with ISO revealed that SGR 1806-20 is in a cluster of giant massive stars, still enshrouded in a dense cloud of gas and dust. SGR 1900+14 is at the edge of a simi

Florian Kerber, Elise Furlan, Thomas Rauch, Miguel Roth

We present results of an ongoing survey of low surface brightness planetary nebulae (PNe). Using both narrow-band imaging and long slit spectroscopy we have studied 15 new examples for interaction with the interstellar medium (ISM) demonstrating that this process is common in evolved PNe. Characteristic properties of the nebulae in terms of morphology and pl

Frederic Daigne, Robert Mochkovitch

The source of cosmic gamma-ray bursts (hereafter GRBs) is usually believed to be a stellar mass black hole accreting material from a thick disk. The mechanism for the production of a relativistic wind by such a system is still unknown. We investigate here one of the proposal where the disk energy is extracted by a magnetic field amplified to very large value

Joerg Schumacher, Bernhard Kliem, Norbert Seehafer

Magnetic reconnection in an antiparallel uniform Harris current sheet equilibrium, which is initially perturbed by a region of enhanced resistivity limited in all three dimensions, is investigated through compressible magnetohydrodynamic simulations. Variable resistivity, coupled to the dynamics of the plasma by an electron-ion drift velocity criterion, is u

J. Kube, B. T. Gaensicke, K. Beuermann

We present a new method to map the surface brightness of the accretion streams in AM Herculis systems from observed light curves. Extensive tests of the algorithm show that it reliably reproduces the intensity distribution of the stream for data with a signal-to-noise ratio >5. As a first application, we map the accretion stream emission of Civ lambda 1550 i

Avishay Gal-Yam, Dan Maoz

Supernovae (SNe) play a critical role in the metal enrichment of the intra-cluster medium (ICM) in galaxy clusters. Not only are SNe the main source for metals, but they may also supply the energy to eject enriched gas from galaxies by winds. However, measurements of SN rates in galaxy clusters have not been published to date. We have initiated a program to

L. L. Kiss, J. Vinko

We present new high-resolution (R=40000) spectroscopic observations of 18 bright northern Cepheids carried out at David Dunlap Observatory, in 1997. The measurements mainly extend those of presented in Paper I adding three more stars (AW Per, SV Vul, T Mon). The spectra were obtained in the interval of 5900 A and 6660 A. New radial velocities determined with

H. J. van Langevelde, Y. M. Pihlstroem, J. E. Conway, W. Jaffe

We report on high sensitivity, spectral line VLBI observations of the HI absorption feature in the radio galaxy NGC4261. Although absorption is only detectable on the most sensitive baseline, it can be unambiguously associated with the counterjet and is interpreted to originate in a thin atomic circumnuclear disk. This structure is probably a continuation of

Heino Falcke, Neil M. Nagar, Andrew S. Wilson, Luis C. Ho

We have surveyed two large samples of nearby low-luminosity AGN with the VLA to search for flat-spectrum radio cores, similar to Sgr A* in the Galactic Center. Roughly one third of all galaxies are detected (roughly one half if HII transition objects are excluded from the sample), many of which have compact radio cores. Follow-up observations with the VLBA h

D. McConnell, J. G. Ables

We present ATCA radio images of the globular cluster 47 Tucanae made at 1.4 and 1.7 GHz and provide an analysis of the radio sources detected within 5 arcmin of the cluster centre. 11 sources are detected, most of which are clustered about the core of 47 Tuc. Both of the pulsars in 47 Tuc whose positions are known can be identified with sources in the 1.4 GH

Simon Portegies Zwart

The high stellar densities in young compact star clusters, such as the star cluster R 136 in the 30 Doradus region, may lead to a large number of stellar collisions. Such collisions were recently found to be much more frequent than previous estimates. The number of collisions scales with the number of stars for clusters with the same initial relaxation time.

A. Konechny, A. Schwarz

It was shown by A. Connes, M. Douglas and A. Schwarz that noncommutative tori arise naturally in consideration of toroidal compactifications of M(atrix) theory. A similar analysis of toroidal Z_{2} orbifolds leads to the algebra B_θ that can be defined as a crossed product of noncommutative torus and the group Z_{2}. Our paper is devoted to the study of proj

Alejandro Kunold, Manuel Torres

We investigate Bloch electrons in two dimensions subject to constant electric and magnetic fields. The model that results from our pursuit is governed by a finite difference equation with a quasienergy spectrum that interpolates between a butterfly-like structure and a Stark ladder structure. These findings ensued from the use of electric and magnetic transl

Andres Gomberoff, Donald Marolf

We study a family of BPS solutions of type IIA supergravity that can be interpreted as describing the `transmutation&#39; of a Neveu-Schwarz five-brane into a D4-brane in the presence of a D6-brane. The D4-brane, which terminates on the D6-brane, can be equally well interpreted as a `pure multipole&#39; configuration of NS5-brane wrapped tightly around the D

Ramon Aguado, David C. Langreth

The out-of-equilibrium transport properties of a double quantum dot system in the Kondo regime are studied theoretically by means of a two-impurity Anderson hamiltonian with interimpurity hopping. The hamiltonian is solved by means of a non-equilibrium generalization of the slave-boson mean-field theory. It is demonstrated that measurements of the differenti

Alberto Frizzo, Lorenzo Magnea, Rodolfo Russo

We describe in detail the techniques needed to compute scattering amplitudes for colored scalars from the infinite tension limit of bosonic string theory, up to two loops. These techniques apply both to cubic and quartic interactions, and to planar as well as non-planar diagrams. The resulting field theories are naturally defined in the space-time dimension

Tianjun Li

If the fifth dimension is one-dimensional connected manifold, up to diffeomorphic, the only possible space-time will be $M^4 \times R^1$, $M^4 \times R^1/Z_2$, $M^4 \times S^1$ and $M^4 \times S^1/Z_2$. And there exist two possibilities on cosmology constant along the fifth dimension: the cosmology constant is constant, and the cosmology constant is sectiona

Joop Schaye, Tom Theuns, Michael Rauch, George Efstathiou

At redshifts z >~ 2, most of the baryons reside in the smooth intergalactic medium which is responsible for the low column density Lyman-alpha forest. This photoheated gas follows a tight temperature-density relation which introduces a cut-off in the distribution of widths of the Lyman-alpha absorption lines (b-parameters) as a function of column density. We

Cheuk-Yin Wong, E. S. Swanson, T. Barnes

We evaluate the cross sections for the dissociation of $J/ψ$ and $ψ&#39;$ by $π$ and $ρ$ at low collision energies, using the quark-interchange model of Barnes and Swanson. The dissociation cross section for $J/ψ$ by $π$ is found to be relatively small with a maximum of about 1 mb and a kinetic energy threshold of 0.65 GeV. The pion-induced $ψ&#39;$ dissocia

N. Andrei, E. Orignac

We determine exactly the fixed point Hamiltonian of the one dimensional multichannel Kondo-Heisenberg lattice model for any number of channels N>=2. An anomalous singlet with non trivial internal dynamics is generated. We compute the correlation functions of the various conventional and unconventional order parameters of the system and find that for N<=4 the

Enrico Lunghi, Ignazio Scimemi

We study the effect of new flavor changing SUSY phases arising in the squark mass matrix in semileptonic decays B->Xs ll and B->K(*) ll (l=e,mu). SUSY effects are parametrized using the mass insertion approximation formalism. Constraints on SUSY contributions coming from other processes (e.g. b->s gamma, B->K* ll) are taken into account. Chargino and gluino

Sedigheh Deldar

The potentials between static sources in various representaions in SU(3) are calculated based on the fat-center-vortices model of Faber, Greensite and Olejnik. At intermediate distances, most distributions of the flux within vortices lead to potentials that are qualitatively in agreement with ``Casimir scaling,'' which says that the string tension is proport

S. A. Abel, A. Dedes, H. K. Dreiner

We show that in the MSSM without R-parity symmetry there are no new contributions to electron and neutron electric dipole moments (EDMs) at 1-loop induced by the R-parity violating Yukawa couplings. Non-zero EDMs for the electron and neutron first arise at the 2-loop level. As an example we estimate the contribution of a two-loop graph which induces electron

Ziwei Lin, C. M. Ko

The cross sections for $J/ψ$ absorption by $π$ and $ρ$ mesons are studied in a meson-exchange model that includes not only pseudoscalar-pseudoscalar-vector-meson couplings but also three-vector-meson and four-point couplings. We find that they are much larger than in a previous study where only pseudoscalar-pseudoscalar-vector-meson couplings were considered

A. A. Deriglazov, K. E. Evdokimov

We study in the Hamiltonian framework the local transformations $δ_εq^A(τ)=\sum^{[k]}_{k=0}\partial^k_τε^a{} R_{(k)a}{}^A(q^B, \dot q^C)$ which leave invariant the Lagrangian action: $δ_εS=div$. Manifest form of the symmetry and the corresponding Noether identities is obtained in the first order formalism as well as in the Hamiltonian one. The identities has

Anne M Green

The simplest interpretation of the microlensing events observed towards the Large Magellanic Clouds is that approximately half of the mass of the Milky Way halo is in the form of MAssive Compact Halo Objects with $M \sim 0.5 M_{\odot}$. It is not possible, due to limits from star counts and chemical abundance arguments, for faint stars or white dwarves to co

Maximilian Kreuzer, Jian-Ge Zhou

Background independence of noncommutative Yang-Mills theory on $\mathbb R^n$ is discussed. The quantity $θ\hat F θ- θ$ is found to be background dependent at subleading order, and it becomes background independent only when the ordinary gauge field strength $F$ is constant. It is shown that, at small values of $B$, the noncommutative Dirac-Born-Infeld action

G. Lambiase, G. Scarpetta, V. V. Nesterenko

In the $(ε_1-ε_2)^2$--approximation the Casimir energy of a dilute dielectric ball is derived using a simple and clear method of the mode summation. The addition theorem for the Bessel functions enables one to present in a closed form the sum over the angular momentum before the integration over the imaginary frequencies. The linear in $(ε_1-ε_2)$ contributi

Donam Youm

We study dynamics of a probe p-brane and a test particle in the field background of fully localized solutions describing the source p-brane within the worldvolume of the source domain wall. We find that the probe dynamics in the background of the source p-brane in one lower dimensions is not reproduced, indicating that p-branes within the worldvolume of doma

A. Bamberger, S. Böttcher, I. Bohnet, J. P. Fernández

A Forward Plug Calorimeter (FPC) for the ZEUS detector at HERA has been built as a shashlik lead-scintillator calorimeter with wave length shifter fiber readout. Before installation it was tested and calibrated using the X5 test beam facility of the SPS accelerator at CERN. Electron, muon and pion beams in the momentum range of 10 to 100 GeV/c were used. Res

B. Jackson, J. F. McCann, C. S. Adams

We solve the Gross-Pitaevskii equation to study energy transfer from an oscillating `object&#39; to a trapped Bose-Einstein condensate. Two regimes are found: for object velocities below a critical value, energy is transferred by excitation of phonons at the motion extrema; while above the critical velocity, energy transfer is via vortex formation. The secon

A. Perali, C. Castellani, C. Di Castro, M. Grilli

Various properties of underdoped superconducting cuprates, including the momentum-dependent pseudogap opening, indicate a behavior which is neither BCS nor Bose-Einstein condensation (BEC) like. To explain this issue we introduce a two-gap model. This model assumes an anisotropic pairing interaction among two kinds of fermions with small and large Fermi velo

J. F. Feinstein

In this note we construct Swiss cheeses X such that R(X) is non-regular but such that R(X) has no non-trivial Jensen measures. We also construct a non-regular uniform algebra with compact, metrizable character space such that every point of the character space is a peak point.

Jes Madsen

R-mode instabilities in rapidly rotating quark matter stars (strange stars) lead to specific signatures in the evolution of pulsars with periods below 2.5 msec, and may explain the apparent lack of very rapid pulsars. Existing data seem consistent with pulsars being strange stars with a normal quark matter phase surrounded by an insulating nuclear crust. In

Stefan Rommer, Steven R. White, D. J. Scalapino

The phase separation boundary of isotropic t-J ladders is analyzed using density matrix renormalization group techniques. The complete boundary to phase separation as a function of J/t and doping is determined for a chain and for ladders with two, three and four legs. Six-chain ladders have been analyzed at low hole doping. We use a direct approach in which

Claudio Meneghini

We propose to apply the idea of analytical continuation in the complex domain to the problem of geodesic completeness. We shall analyse rather in detail the cases of analytical warped products of real lines, these ones in parallel with their complex counterparts, and of Clifton-Pohl torus, to show that our definition sheds a bit of new light on the behaviour

Enrico Carlon, Malte Henkel, Ulrich Schollwoeck

The steady-state phase diagram of the one-dimensional reaction-diffusion model 2A -> 3A, 2A -> 0 is studied through the non-hermitian density matrix renormalization group. In the absence of single-particle diffusion the model reduces to the pair-contact process, which has a phase transition in the universality class of Directed Percolation (DP) and an infini

Tom Broadhurst, Evan Scannapieco

We examine the gravitational redshift of radiation emitted from within the potential of a cluster. Spectral lines from the intracluster medium (ICM) are redshifted in proportion to the emission-weighted mean potential along the line of sight, amounting to approximately 50 km/s at a radius of 100 kpc/h, for a cluster dispersion of 1200 km/s. We show that the

Andrew Chamblin, Douglas M. Eardley

We investigate the semi-classical instability of vacuum domain walls to processes where the domain walls decay by the formation of closed string loop boundaries on their worldvolumes. Intuitively, a wall which is initially spherical may `pop&#39;, so that a hole corresponding to a string boundary component on the wall, may form. We find instantons, and calcu

Jiannis Pachos, Spiros Chountasis

In this paper the idea of holonomic quantum computation is realized within quantum optics. In a non-linear Kerr medium the degenerate states of laser beams are interpreted as qubits. Displacing devices, squeezing devices and interferometers provide the classical control parameter space where the adiabatic loops are performed. This results into logical gates

S. A. Gardiner, D. Jaksch, R. Dum, J. I. Cirac

We consider the case of a cubic nonlinear Schrödinger equation with an additional chaotic potential, in the sense that such a potential produces chaotic dynamics in classical mechanics. We derive and describe an appropriate semiclassical limit to such a nonlinear Schrödinger equation, using a semiclassical interpretation of the Wigner function, and relate th

Frederic Faure, Boris Zhilinskii

Topological Chern indices are related to the number of rotational states in each molecular vibrational band. Modification of the indices is associated to the appearance of ``band degeneracies&#39;&#39;, and exchange of rotational states between two consecutive bands. The topological dynamical origin of these indices is proven through a semi-classical approac

J. Ortner, I. Valuev, W. Ebeling

The semiclassical dynamics of a charged particle moving in a two-component plasma is considered using a corrected Kelbg pseudopotential. We employ the classical Nevanlinna-type theory of frequency moments to determine the velocity and force autocorrelation functions. The constructed expressions preserve the exact short and long-time behavior of the autocorre

N. Sandulescu, O. Civitarese, R. J. Liotta

The temperature dependent BCS equations are modified in order to include the contribution of the continuum single particle states. The influence of the continuum upon the critical temperature corresponding to the phase transition from a superfluid to a normal state and upon the behaviour of the excitation energy and of the entropy is discussed.

A. J. Buchmann, E. M. Henley

We have extended and applied a general QCD parameterization method to the emission of pions from baryons. We use it to calculate the strength and sign of the coupling of pions to the octet and decuplet of baryons. Certain relations between octet and decuplet couplings are pointed out.

A. Dimakis, C. Tzanakis

By considering a lattice model of extended phase space, and using techniques of noncommutative differential geometry, we are led to: (a) the conception of vector fields as generators of motion and transition probability distributions on the lattice; (b) the emergence of the time direction on the basis of the encoding of probabilities in the lattice structure

Izumi Ojima

A simple and general derivation of Josephson formulae for the tunneling currents is presented on the basis of Sewell&#39;s general formulation of superconductivity in use of off-diagonal long range order (ODLRO).

R. Pandharipande

Consequences of the Toda equations arising from the conjectural matrix model for the Riemann sphere are investigated. The Toda equations determine the Gromov-Witten descendent potential (including all genera) of the Riemann sphere from the degree 0 part. Degree 0 series computations via Hodge integrals then lead to higher degree predictions by the Toda equat

Saharon Shelah

We continue to investigate club guessing (see [Sh:g, Ch III] and [Sh:e, Ch VI]), continuing Dzamonja and Shelah [DjSh:691]

Marco A Garuti

We construct inductively an equivariant compactification of the algebraic group ${\mathbb W}_n$ of Witt vectors of finite length over a field of characteristic $p>0$. We obtain smooth projective rational varieties $\bar{\mathbb W}_n$, defined over $\mathbf F_p$; the boundary is a divisor whose reduced subscheme has normal crossings. The Artin-Schreier-Witt i

Saharon Shelah

We prove the consistency of the following statement: for some kappa<2^{aleph_0}, there is a kappa-complete ideal on kappa such that the Boolean algebra P(kappa)/I is sigma-centered and there are Q-sets of reals.

Michael T. Anderson

We study Yamabe metrics, and the moduli space of Yamabe metrics, on an arbitrary closed 3-manifold M. The main focus is on the boundary behavior of the moduli space, i.e. the behavior of degenerating sequences of unit volume Yamabe metrics on M. It is proved that such degenerations, when non-trivial in a certain sense, are described by solutions of the stati

J. C. Hurtubise, E. Markman

We exhibit the elliptic Calogero-Moser system as a Hitchin system of G-principal Higgs pairs. The group G, though naturally associated to any root system, is not semi-simple. We then interpret the Lax pairs with spectral parameter of [dP1] and [BSC1] in terms of equivariant embeddings of the Hitchin system of G into that of GL(N).

Hiraku Nakajima

We study finite dimensional representations of the quantum affine algebra, using geometry of quiver varieties introduced by the author. As an application, we obtain character formulas expressed in terms of intersection cohomologies of quiver varieties.

Vladimir Shpilrain, Jie-Tai Yu

The &#34;peak reduction&#34; method is a powerful combinatorial technique with applications in many different areas of mathematics as well as theoretical computer science. It was introduced by Whitehead, a famous topologist and group theorist, who used it to solve an important algorithmic problem concerning automorphisms of a free group. Since then, this met

Finnur Larusson, Ragnar Sigurdsson

The Jensen envelope $Jϕ$ of an upper semicontinuous function $ϕ$ on a complex manifold X is defined at $x\in X$ as the infimum of $μ(ϕ)$ over all Jensen measures $μ$ centred at x. The Poisson envelope $Pϕ$ is defined by using only the boundary measures of analytic discs centred at x. One of the main open problems in the theory of disc functionals is whether

Michael Haack, Jan Louis

We study heterotic vacua with four supercharges in three and four space-time dimensions and their duals obtained as M/F-theory compactified on Calabi-Yau fourfolds. We focus on their respective moduli spaces and derive the Kahler potential for heterotic vacua obtained as circle compactifications of four-dimensional N=1 heterotic theories. The Kahler potentia

I. Krichever, D. H. Phong

We construct the integrable model corresponding to the $\N=2$ supersymmetric SU(N) gauge theory with matter in the antisymmetric representation, using the spectral curve found by Landsteiner and Lopez through M Theory. The model turns out to be the Hamiltonian reduction of a $N+2$ periodic spin chain model, which is Hamiltonian with respect to the universal

Dirk Olivie

A gauge transformation in quantum electrodynamics involves the product of field operators at the same space-time point and hence does not have a well-defined meaning. One way to avoid this difficulty is to generalize the gauge transformation by using different space-time points in the spirit of Dirac&#39;s point splitting. Such a generalization indeed exists

P. M. Llatas, A. V. Ramallo, J. M. Sanchez de Santos

We analyze the world-volume solitons of a D3-brane probe in the background of parallel (p,q) five-branes. The D3-brane is embedded along the directions transverse to the five-branes of the background. By using the S-duality invariance of the D3-brane, we find a first-order differential equation whose solutions saturate an energy bound. The SO(3) invariant so

J. Balog, L. Feher, L. Palla

This is a review of recent work on the chiral extensions of the WZNW phase space describing both the extensions based on fields with generic monodromy as well as those using Bloch waves with diagonal monodromy. The symplectic form on the extended phase space is inverted in both cases and the chiral WZNW fields are found to satisfy quadratic Poisson bracket r

D. G. Pak

Three-dimensional bicovariant differential calculus on the quantum group SU_q(2) is constructed using the approach based on global covariance under the action of the stabilizing subgroup U(1). Explicit representations of possible q-deformed Lie algebras are obtained in terms of differential operators. The consistent gauge covariant differential calculus on S

S. Dawson

Any consideration of future physics facilities must be made in the context of the Tevatron and the LHC. I discuss some examples of physics results which could emerge from these machines and the resulting questions which would remain for a high energy $e^+e^-$ collider. Particular attention is paid to the electroweak symmetry breaking sector. If a light Higgs

Jusak Tandean

We present a discussion of the |Delta I|=3/2 amplitudes of the hyperon decays B->B&#39;+pi in the context of chiral perturbation theory. We evaluate the theoretical uncertainty of the lowest-order predictions by calculating the leading non-analytic corrections. We find that the corrections to the lowest-order predictions are within the expectations of naive

Carlo Giunti

We consider the scheme with mixing of three neutrinos and a mass hierarchy. We shown that, under the natural assumptions that massive neutrinos are Majorana particles and there are no unlikely fine-tuned cancellations among the contributions of the different neutrino masses, the results of solar neutrino experiments imply a lower bound for the effective Majo

F. Benatti, R. Floreanini

A phenomenological paradigm for the study of CPT-violating effects in the neutral kaon system is presented. Besides the familiar direct and indirect breakings, it encodes possible phenomena leading to irreversibility and dissipation, that could originate from quantum effects at Planck&#39;s scale. These new effects can be experimentally probed with great acc

A. K. Likhoded, A. I. Onishchenko

We perform a detailed investigation of total lifetimes for the doubly heavy baryons $Ξ_{QQ&#39;}$, $Ω_{QQ&#39;}$ in the framework of operator product expansion over the inverse heavy quark mass, whereas, to estimate matrix elements of operators obtained in OPE, approximations of nonrelativistic QCD are used.

Andrei I. Onishchenko

We discuss questions related to the application of OPE for the long-lived systems with two heavy flavors. The values of quark masses entering such calulations are constrained by use of currently available data on the lifetimes of $B_d$ and $B_c$-mesons. The lifetimes of doubly charmed baryons at these values of parameters are evaluated. The necessary comment

J. Bartels, L. N. Lipatov, G. P. Vacca

We present and discuss a new bound state solution of the three gluon system in perturbative QCD. It carries the quantum numbers of the odderon, has intercept at one and couples to the impact factor $γ^* \to η_c$.

M. Yu. Khlopov, R. V. Konoplich, S. G. Rubin, A. S. Sakharov

A new mechanism of black hole formation in a first order phase transition is proposed. In vacuum bubble collisions the interaction of bubble walls leads to the formation of nontrivial vacuum configuration. The consequent collapse of this vacuum configuration induces the black hole formation with high probability. The primordial black holes that have been cre

P. A. Baikov

The integration by parts recurrence relations allow to reduce some Feynman integrals to more simple ones (with some lines missing). Nevertheless the possibility of such reduction for the given particular integral was unclear. The recently proposed technique for studying the recurrence relations as by-product provides with simple criterion of the irreducibili

C. Greub, T. Hurth, D. Wyler

QCD corrections to the gluino induced contribution to b --> s gamma are shown to be important in order to extract reliable bounds on the off-diagonal elements of the squark mass matrices.

H. Heiselberg

Color superconductivity in quark matter is studied for electrically charge neutral neutron star matter in $β$-equilibrium. Both bulk quark matter and mixed phases of quark and nuclear matter are treated. The electron chemical potential and strange quark mass affect the various quark chemical potentials and therefore also the color superconductivity due to di

S. Atag, I. T. Cakir

The potential of LC+HERA based gamma-p collider to probe WW-gamma vertex is presented through the discussion of sensitivity to anomalous couplings and p_{T} distribution of the final quark. The limits of -0.16<(kappa-1)<0.14, -0.30<lambda<0.30, at 95% C.L. can be reached with integrated luminosity 100pb^{-1} and they are competitive to projected future limit

Athar Husain

I discuss the possibility of production of high energy cosmic tau neutrinos ($E \geq 10^{6}$ GeV) in an astrophysical site and study some of the effects of neutrino mixing on their subsequent propagation. I also discuss the prospects for observations of these high energy cosmic tau neutrinos through double shower events in new km$^{2}$ surface area under wat

William E. Brown, James T. Liu, Hai-cang Ren

Recent interest in the study of color superconductivity has focused on the regime of high baryon density where perturbative QCD may be employed. Based on the dominant one-gluon-exchange interaction, both the transition temperature and zero temperature gap have been determined to leading order in the coupling, g. While the leading non-BCS behavior, $T_C\simμg

B. Machet

The paper has been withdrawn

Meng Ta-chung, R. Rittel, K. Tabelow, Zhang Yang

It is shown that meson radii can be extracted from diffractive scattering experiments of the type: $m+p\to m + X$, where p stands for the target proton, and m for the incident charged meson $π^+$, $π^-$, $K^+$, or $K^-$. The basis of the method used to perform this extraction is the QCD-based SOC-picture for inelastic diffraction in high-energy hadron-hadron

Massimo Testa

Some general considerations on the problem of non-perturbative definition of Chiral Gauge Theories are presented.

Michel Davier

Hadronic decays of the $τ$ lepton provide a clean source to study hadron dynamics in an energy regime dominated by resonances, with the interesting information captured in the spectral functions. Recent results on exclusive channels are reviewed. Inclusive spectral functions are the basis for QCD analyses, delivering an accurate determination of the strong c

J. M. Pons, D. C. Salisbury, L. C. Shepley

We discuss the relation between spacetime diffeomorphisms and gauge transformations in theories of the Yang-Mills type coupled with Einstein&#39;s General Relativity. We show that local symmetries of the Hamiltonian and Lagrangian formalisms of these generally covariant gauge systems are equivalent when gauge transformations are required to induce transforma

J. M. Pons, D. C. Salisbury, L. C. Shepley

We discuss reality conditions and the relation between spacetime diffeomorphisms and gauge transformations in Ashtekar&#39;s complex formulation of general relativity. We produce a general theoretical framework for the stabilization algorithm for the reality conditions, which is different from Dirac&#39;s method of stabilization of constraints. We solve the