March 2002 arXiv papers — page 17

M. Brightwell, P. Turner

We study a variation of Turaev's homotopy quantum field theories using 2-categories of surfaces. We define the homotopy surface 2-category of a space $X$ and define an $\cS_X$-structure to be a monoidal 2-functor from this to the 2-category of idempotent-complete additive $k$-linear categories. We initiate the study of the algebraic structure arising fro

Peter S Ozsvath, Zoltan Szabo

In an earlier paper (math.SG/0110169), we introduced absolute gradings on the three-manifold invariants developed in math.SG/0101206 and math.SG/0105202. Coupled with the surgery long exact sequences, we obtain a number of three- and four-dimensional applications of this absolute grading including strengthenings of the ``complexity bounds'' (from mat

Alexander Retakh

Pseudoalgebras, introduced in [BDK], are multi-dimensional analogues of conformal algebras, which provide an axiomatic description of the singular part of the operator product expansion. Our main interest in this paper is the pseudoalgebra Cend_n, which is the analogue of an algebra of endomorphisms of a finite module. We study its algebraic properties. In p

Nguyen Tien Zung

We show that, to find a Poincare-Dulac normalization for a vector field is the same as to find and linearize a torus action which preserves the vector field. Using this toric characterization and other geometrical arguments, we prove that any local analytic vector field which is integrable in the non-Hamiltonian sense admits a local convergent Poincare-Dulac

J. Besprosvany

We consider a Dirac equation set on an extended spin space that contains fermion and boson solutions. At given dimension, it determines the scalar symmetries. The standard field equations can be equivalently written in terms of such degrees of freedom, and are similarly constrained. At 9+1 dimensions, the SU(3) X SU(2)_L X U(1) gauge groups emerge, as well a

Giorgio Immirzi, Badis Ydri

In this talk we give a brief description of the formulation of chiral and gauge symmetries on the fuzzy sphere . In particular fermion doublers are shown to be absent and the correct anomaly equation in two dimensions is obtained in the corresponding continuum limit .

Tony Gherghetta, Alex Pomarol

We consider supersymmetric theories with a warped extra dimension where supersymmetry is broken by boundary conditions that preserve an R-symmetry. It is shown that this supersymmetry breaking mechanism naturally invokes the Stuckelberg formalism for the gravitino in order to give a four-dimensional theory with a smooth massless limit.

Robert Brandenberger, Pei-Ming Ho

We propose a variation of spacetime noncommutative field theory to realize the stringy spacetime uncertainty relation without breaking any of the global symmetries of the homogeneous isotropic universe. We study the spectrum of metric perturbations in this model for a wide class of accelerating background cosmologies. Spacetime noncommutativity leads to a co

F. Loran

It is possible to introduce external time dependent back ground fields in the formulation of a system as fields whose dynamics can not be deduced from Euler Lagrange equations of motion. This method leads to singular Lagrangians for real systems. We discuss quantization of constraint systems in these cases and introduce generalized Gupta-Bleuler quantization

J. Wosiek

The new method of solving quantum mechanical problems is proposed. The finite, i.e. cut off, Hilbert space is algebraically implemented in the computer code with states represented by lists of variable length. Complete numerical solution of a given system is then automatically obtained. The technique is applied to Wess-Zumino quantum mechanics and D=2 and D=

A. I. Davydychev, K. Schilcher, H. Spiesberger

We consider the O(alpha^2) hadronic corrections to the energy spectrum of the decay electron in muon decay. We find that the correction can be described, within good approximation, by a linear function in the electron energy. Explicit expressions for the form factors needed in an approach based on dispersion integrals are given.

Dieter Zeppenfeld

The observation of a SM-like Higgs boson in multiple channels at the LHC allows the extraction of Higgs couplings to gauge bosons and fermions. The precision achievable at the LHC, for an integrated luminosity of 200 fb^{-1}, is reviewed and updated.

Stefan Dittmaier, Andreas Kaiser

The photonic and QCD radiative corrections at next-to-leading order are calculated for fermion-pair production at muon colliders, maintaining the full mass dependence and helicity information of the muons and the produced fermions. Higher-order effects of initial-state radiation are included at the leading logarithmic level. In the calculation particular att

Ljuba Skovrlj, Tomislav Ivezic

In this paper it is proved that, contrary to the results found by A.E. Chubykalo and S.J. Vlaev (Int. J. Mod. Phys. A 14, 3789 (1999)), the retarded electric and magnetic fields for an uniformly accelerated charge exactly satisfy Maxwell equations (ME). Furthermore it is shown that ME are correctly written in the usual form with the partial derivatives and t

John Ellis

These lectures provide a phenomenological introduction to supersymmetry, concentrating on the minimal supersymmetric extension of the Standard Model (MSSM). In the first lecture, motivations are provided for thinking that supersymmetry might appear at the TeV scale, including the naturalness of the mass hierarchy, gauge unification and the probable mass of t

Vladimir G. Baryshevsky, Dmitry N. Matsukevich

Rotation of polarization plane of light in gas placed in electric field is considered. Different factors causing this phenomenon are investigated. Angle of polarization plane rotation for transition 6S_{1/2} - 7S_{1/2} in cesium (lambda=539 nm) is estimated. The possibility to observe this effect experimentally is discussed.

KARMEN collaboration, B. Armbruster, I. M. Blair, B. A. Bodmann

The KARMEN experiment at the spallation neutron source ISIS used \numub from \mup--decay at rest in the search for neutrino oscillations \numubnueb in the appearance mode, with p(\nueb,e+)n as detection reaction of \nueb. In total, 15 candidates fulfill all conditions for the \nueb signature, in agreement with the background expectation of 15.8+-0.5 events,

ALEPH Collaboration

A search for charginos nearly mass degenerate with the lightest neutralino is performed with the data collected by the ALEPH detector at LEP, at centre-of-mass energies between 189 and 209 GeV, corresponding to an integrated luminosity of 628 pb-1. The analysis is based on the detection of isolated and energetic initial state radiation photons, produced in a

G. Azuelos, D. Benchekroun, O. Cakir, E. Elfgren

The impact on the physics capabilities of the ATLAS detector of possible LHC upgrades is discussed. As a benchmark, an increase in the luminosity by a factor of ten is considered. For comparison, a doubling of the LHC energy is also explored. Both upgrades significantly enhance the physics capabilities of ATLAS. As measured in terms of the mass reach for new

S. Dain, O. M. Moreschi

We report a new result on the nice section construction used in the definition of rest frame systems in general relativity. This construction is needed in the study of non trivial gravitational radiating systems. We prove existence, regularity and non-self-crossing property of solutions of the nice section equation for general asymptotically flat space times

W. B. Bonnor

I derive an exact, static, axially symmetric solution of the Einstein-Maxwell equations representing two massless magnetic dipoles, and compare it with the corresponding solution of Einstein's equations for two massless spinning particles (see gr-qc/0201094). I then obtain an exact stationary solution of the Einstein-Maxwell equations representing two ma

W. B. Bonnor

Using Einstein-Maxwell theory I investigate the gravitational field generated by an electric charge and a magnetic dipole, both held in fixed positions, but spinning with prescribed angular momenta. There is a conical singularity between them representing a strut balancing the gravitational attraction of their masses. However, there is in general another sin

Vladimir S. Mashkevich

The universe, as a closed system, is for all time in a state with a determinate value of energy, i.e., in an eigenstate of the Hamiltonian. That is the principle of cosmic energy determinacy. The Hamiltonian depends on cosmic time through metric. Therefore there are confluence and branch points of energy levels. At branch points, quantum jumps must happen to

James Isenberg

The first step in the building of a spacetime solution of Einstein's gravitational field equations via the initial value formulation is finding a solution of the Einstein constraint equations. We recall the conformal method for constructing solutions of the constraints and we recall what it tells us about the parameterization of the space of such solutio

Adam L. Buchsbaum, Glenn S. Fowler, Raffaele Giancarlo

We study the problem of compressing massive tables within the partition-training paradigm introduced by Buchsbaum et al. [SODA'00], in which a table is partitioned by an off-line training procedure into disjoint intervals of columns, each of which is compressed separately by a standard, on-line compressor like gzip. We provide a new theory that unifies p

A. S. Alexandrov, P. E. Kornilovitch

We introduce a generic Froehlich-Coulomb model of the oxides, which also includes infinite on-site (Hubbard) repulsion, and describe a simple analytical method of solving the multi-polaron problem in complex lattice structures. Two particular lattices, a zig-zag ladder and a perovskite layer, are studied. We find that depending on the relative strength of th

D. P. Varn, G. S. Canright, J. P. Crutchfield

We solve a longstanding problem--determining structural information for disordered materials from their diffraction spectra--for the case of planar disorder in close-packed structures (CPSs). Our solution offers the most complete possible statistical description of the disorder, and, from it, we find the minimum effective memory length of disordered stacking

Martin Greiter

We introduce a novel kind of spin liquid, the spin 1 chirality liquid, which provides a generic paradigm for a disordered spin 1 antiferromagnet in two dimensions. It supports spinon and holon excitations, which carry a chirality quantum number. These excitations obey half-fermi statistics. The sign of the statistical parameter is determined by the chirality

V. W. Scarola, J. K. Jain, E. H. Rezayi

We report on our theoretical investigations that point to the possibility of a fractional quantum Hall effect with partial spin polarization at $ν=3/8$. The physics of the incompressible state proposed here involves p-wave pairing of composite fermions in the spin reversed sector. The temperature and magnetic field regimes for the realization of this state a

J. M. Vogels, K. Xu, W. Ketterle

By colliding two Bose-Einstein condensates we have observed strong bosonic stimulation of the elastic scattering process. When a weak input beam was applied as a seed, it was amplified by a factor of 20. This large gain atomic four-wave mixing resulted in the generation of two macroscopically occupied pair-correlated atomic beams.

C. Ciuti, J. P. McGuire, L. J. Sham

We present a theory of the imprinting of the electron spin coherence and population in an n-doped semiconductor which forms a junction with a ferromagnet. The reflection of non-equilibrium semiconductor electrons at the interface provides a mechanism to manipulate the spin polarization vector. In the case of unpolarized excitation, this ballistic effect prod

Marco Cannas

The optical properties of point defects in as-grown natural silica are reviewed. Two emissions peaked at 4.2 eV ($α_E$ band) and at 3.1 eV ($β$ band), related to an absorption band at 5.1 eV ($B_{2β}$), have been experimentally investigated on the basis of their temperature dependence and their kinetic decay. Our results allow to characterize the excitation

E. H. Hwang, S. Das Sarma

We calculate the temperature dependent resistivity in spin-split subbands induced by the inversion asymmetry of the confining potential in GaAs 2D hole systems. By considering both temperature dependent multisubband screening of impurity disorder and hole-hole scattering we find that the strength of the metallic behavior depends on the symmetry of the confin

S. Agnello, R. Boscaino, G. Buscarino, M. Cannas

We report experimental evidence of the existence of two variants of the E' gamma centers induced in silica by gamma rays at room temperature. The two variants are distinguishable by the fine features of their line shapes in paramagnetic resonance spectra. These features suggest that the two E' gamma differ for their topology. We find a thermally indu

M. V. Kartsovnik, P. D. Grigoriev, W. Biberacher, N. D. Kushch

Slow oscillations of the interlayer magnetoresistance observed in the layered organic metal $β$-(BEDT-TTF)$_2$IBr$_2$ are shown to originate from the slight warping of its Fermi surface rather than from independent small cyclotron orbits. Unlike the usual Shubnikov-de Haas effect, these oscillations are not affected by the temperature smearing of the Fermi d

S. Stolbov, T. S. Rahman

The electronic structure of the $(2\sqrt{2}\times\sqrt{2})R45^{\circ}$ O/Cu(001) system has been calculated using locally self-consistent, real space multiple scattering technique based on first principles. Oxygen atoms are found to perturb differentially the long-range Madelung potentials, and hence the local electronic subbands at neighboring Cu sites. As

V. T. Dolgopolov, A. Gold

Comment on: Weak Anisotropy and Disorder Dependence of the In-Plane Magnetoresistance in High-Mobility (100) Si Inversion Layers

D. Benedetto, E. Caglioti, V. Loreto

Motivated by the recent submission to cond-mat archives by J. Goodman (cond-mat/0202383) whose results apparently discredit the approach we have proposed in a recent paper (Phys. Rev. Lett., 88, 048702 (2002), cond-mat/0108530), we report the results of the same experiment performed by Goodman using three different data compression schemes. As a matter of fa

Jihong Qin, Yun Song, Shiping Feng, Wei Yeu Chen

Within the t-J model, the optical and transport properties of the doped two-leg ladder antiferromagnet are studied based on the fermion-spin theory. It is shown that the optical and transport properties of the doped two-leg ladder antiferromagnet are mainly governed by the holon scattering. The low energy peak in the optical conductivity is located at a fini

Yusuke Kato, Nobuhiko Hayashi

The impurity problems within vortex cores of two-dimensional s-wave and chiral p-wave superconductors are studied numerically in the framework of the quasiclassical theory of superconductivity and self-consistent Born approximation under a trial form of the pair potential. The dispersion and impurity scattering rate (the inverse of the relaxation time) of th

H. -J. Schmidt

Recently obtained results on linear energy bounds are generalized to arbitrary spin quantum numbers and coupling schemes. Thereby the class of so-called independent magnon states, for which the relative ground-state property can be rigorously established, is considerably enlarged. We still require that the matrix of exchange parameters has constant row sums,

Ivan Kupcic

The single-particle contributions to the optical conductivity of the quasi-one-dimensional systems has been reexamined by using the gauge-invariant transverse microscopic approach. The valence electrons are described by a model with the weak bond-energy dimerization, while the relaxation processes are taken into account phenomenologically. It turns out that

Alvin Chua, Kim Christensen

We determine analytically the number $N_{\mathcal{R}}(L)$ of recurrent states in the 1d Oslo model as a function of system size L. The solution $N_{\mathcal{R}}(L) = \frac{1+\sqrt{5}}{2\sqrt{5}}(\frac{3+\sqrt{5}}{2})^L + \frac{\sqrt{5}-1}{2\sqrt{5}}(\frac{3-\sqrt{5}}{2})^L$ is in exact agreement with the number enumerated in computer simulations for $L = 1 -

Anatoli Polkovnikov, Matthias Vojta, Subir Sachdev

We present a theory of the pinning of dynamic spin density wave (SDW) fluctuations in a d-wave superconductor by local imperfections which preserve spin-rotation invariance, such as impurities or vortex cores. The pinning leads to static spatial modulations in spin-singlet observables, while the SDW correlations remain dynamic: these are the `Friedel oscilla

Kenneth R. Sembach, Brad K. Gibson, Yeshe Fenner, Mary E. Putman

There is a fortuitous coincidence in the positions of the quasar TonS210 and the compact H I high velocity cloud CHVC224.0-83.4-197 on the sky. Using Far Ultraviolet Spectroscopic Explorer observations of the metal-line absorption in this cloud and sensitive H I 21cm emission observations obtained with the multibeam system at Parkes Observatory, we determine

T. G. Mueller, S. Hotzel, M. Stickel

The ISOPHOT Serendipity Survey (ISOSS) covered approximately 15 % of the sky at a wavelength of 170 micron while the ISO satellite was slewing from one target to the next. By chance ISOSS slews went over many solar system objects (SSOs). We identified the comets, asteroids and planets in the slews through a fast and effective search procedure based on N-body

G. H. Share, R. J. Murphy, J. Kiener, N. de Sereville

The energies and widths of gamma-ray lines emitted by ambient nuclei excited by flare-accelerated protons and alpha particles provide information on the ions directionality and spectra, and on the characteristics of the interaction region. We have measured the energies and widths of strong lines from de-excitations of 12C, 16O, and 20Ne in solar flares as a

J. S. B. Wyithe, E. L. Turner

The fraction of quasar's and gamma-ray burst (GRB) afterglows that vary due to microlensing by the stellar populations of intervening elliptical/S0 galaxies is computed by combining the joint distribution of effective microlensing convergence (kappa) and shear (gamma) with microlensing magnification patterns. Microlensing is common in multiply imaged sou

M. Kuster, J. Wilms, R. Staubert, P. Risse

The X-ray binary pulsar Her X-1 shows a wide variety of long and short term variabilities in the X-ray light curve. The 35 d variability of the source is interpreted as the influence of a warped, inclined, and twisted accretion disk periodically covering the line of sight to the central neutron star. In 1997 September we observed the ``turn-on'' of a

F. V. Prigara

We propose the unified model of compact radio sources, i.e. of pulsars, maser sources, and active galactic nuclei. The unification is based on the wavelength dependence of radio source size. It is shown that the compact sources are characterized by a maser amplification of thermal radio emission. The density, temperature, and magnetic field profiles of compa

Duilia de Mello, T. Wiklind, C. Leitherer, K. Pontoppidan

We present high resolution VLT spectra of 2 submm-detected galaxies. Diagnostic stellar absorption lines (Starburst99) are used to analyse their stellar population. SMM J14011+0252 (z=2.565) shows signs of starburst and SMM J02399-0136 (z=2.808) shows signs of starburst and AGN. A MgII line at z~0.94 is identified in the latter galaxy and could account for a

Felix J. Lockman

HI observations in the 21cm line have been a principal tool for investigating the large-scale structure of the Milky Way. This review considers what was learned in the first decade after the discovery of the 21cm line, and how that knowledge has been expanded and refined in subsequent years. Topics include spiral structure, the Galactic nucleus, the thicknes

Bertrand Plez, David L. Lambert

Spatially-resolved high-resolution long-slit spectra of Betelgeuse's circumstellar shell are described for a spectral window centered on the 7699Åresonance line of neutral potassium. The K I emission from resonance fluorescent scattering of photospheric photons which is mapped out to 50 arcsec from the star is approximately spherically symmetric with a b

Rosalba Perna, Mario Vietri

We derive a fully relativistic, self-similar solution to describe the propagation of a shock along an exponentially decreasing atmosphere, in the limit of very large Lorentz factor. We solve the problem in planar symmetry and compute the acceleration of the shock in terms of the density gradient crossed during its evolution. We apply our solution to the acce

Markus Kuster, Eckhard Kendziorra, Sara Benlloch, Werner Becker

The EPIC pn CCD camera on board of XMM-Newton is designed to perform high throughput imaging and spectroscopy as well as high resolution timing observations in the energy range of 0.1-15 keV. A temporal resolution of milliseconds or microseconds, depending on the instrument mode and detector, is outstanding for CCD based X-ray cameras. In order to calibrate

Maria T. Beltran, Jose M. Girart, Robert Estalella, Paul T. P. Ho

We present centimeter and millimeter observations of gas and dust around IRAS 21391+5802, an intermediate-mass source embedded in the core of IC 1396N. Continuum observations from 3.6 cm to 1.2 mm are used to study the embedded objects and overall distribution of the dust, while molecular line observations of CO, CS, and CH3OH are used to probe the structure

Claudio Rubano, Mauro Sereno

We investigate the evolution of matter density perturbations and some properties of the peculiar velocity field for a special class of exponential potentials in a scalar field model for quintessence, for which a general exact solution is known. The data from the 2-degree Field Galaxy Redshift Survey (2dFGRS) suggest a value of the today pressureless matter d

R. Morganti, T. A. Oosterloo, S. Tinti, C. N. Tadhunter

We present WSRT and VLA radio observations of the neutral hydrogen in the radio galaxy Coma A. We detect extended HI absorption against both radio lobes of Coma A, at distances of about 30 kpc from the centre. Coma A is the first radio galaxy in which HI is seen in absorption at such large distances from the nucleus. The match between the velocities of the n

Roser Pello, Daniel Schaerer

The new Pop III models by Schaerer (2002) have been used to derive the observed properties of the first galaxies in terms of the expected magnitudes and colors. The dependence of their properties on the IMF and upper mass limit for star formation are studied. The emerging synthetic spectra are used to discuss the implications on different observational featu

A. -M. Dumont, B. Czerny, S. Collin, P. T. Zycki

We present a model of the vertical stratification and the spectra of an irradiated medium under the assumption of constant pressure. Such a solution has properties intermediate between constant density models and hydrostatic equilibrium models, and it may represent a flattened configuration of gas clumps accreting onto the central black hole. Such a medium d

Pieter Westera, Markus Samland, Roland Buser, Ortwin Gerhard

We calculate synthetic UBVRIJHKLM images, integrated spectra and colours for the disk galaxy formation models of Samland & Gerhard (2002), from redshift z=4 to z=0. Two models are considered, an accretion model based on LambdaCDM structure formation simulations, and a classical collapse model in a dark matter halo. Both models provide the star formation hist

A. Melchiorri, J. Silk

The nature of dark matter is increasingly constrained by cosmological data. In this paper, we examine the implications of the Cosmic Microwave Background anisotropy limits on the density of cold dark matter under different theoretical assumptions and combinations of datasets. We infer the constraint $Ω_{cdm}h^2=0.12\pm0.04$ (at 95% c.l.). The CDM models are

R. Falomo, J. K. Kotilainen, A. Treves

The correlation between black hole mass M(BH) and stellar velocity dispersion sigma in nearby elliptical galaxies affords a novel way to determine M(BH) in active galaxies. We report on measurements of sigma from optical spectra of 7 BL Lac host galaxies. The derived values of sigma are in the range of 160 - 290 km/s corresponding to M(BH) of 5 x 10^7 to 1 x

S. K. Ghosh, D. K. Ojha

Recently the Midcourse Space Experiment (MSX) has surveyed the Galactic plane in mainly four infrared bands between 6 and 25 micron. Two of these bands cover several Unidentified Infrared emission Bands (UIBs). With the aim of extracting the spatial distribution of the UIB emission on a large scale, a scheme has been developed to model the MSX data with emis

Toshitaka Kajino

Recent observation of the power spectrum of Cosmic Microwave Background (CMB) Radiation has exhibited that the flat cosmology is most likely. This suggests too large universal baryon-density parameter $Ω_b h^2 \approx 0.022 \sim 0.030$ to accept a theoretical prediction, $Ω_b h^2 \le 0.017$, in the homogeneous Big-Bang model for primordial nucleosynthesis. T

Y. -Z. Qian

An r-process scenario with fission but no fission cycling is considered to account for the observed abundance patterns of neutron-capture elements in ultra-metal-poor stars. It is proposed that neutrino reactions play a crucial role in inducing the fission of the progenitor nuclei after the r-process freezes out in Type II Supernovae. To facilitate neutrino-

Y. -Z. Qian, W. L. W. Sargent, G. J. Wasserburg

It has been proposed that very massive stars (VMSs) dominated heavy element production until a metallicity threshold corresponding to [Fe/H]=-3 was reached. This results in a prompt (P) inventory of elements, the abundances of which were determined from observations of Galactic halo stars with [Fe/H]=-3. We calculate Omega_P(E) from the P inventory for a lar

Li-Xin Li, Ramesh Narayan, Kristen Menou

We model the 1990 giant X-ray flare of the quiescent galaxy NGC 5905 as the tidal disruption of a star by a supermassive black hole. From the observed rapid decline of the luminosity, over a timescale of a few years, we argue that the flare was powered by the fallback of debris rather than subsequent accretion via a thin disk. The fallback model allows const

Ian G. McCarthy, Arif Babul, Michael L. Balogh

Recent X-ray observations have been used to demonstrate that the cluster gas mass-temperature relation is steeper than theoretical self-similar predictions drawn from numerical simulations that consider the evolution of the cluster gas through the effects of gravity and shock heating alone. One possible explanation for this is that the gas mass fraction is n

Ivan Soprounov

We introduce a new approach to the study of a system of algebraic equations in the algebraic torus whose Newton polytopes have sufficiently general relative positions. Our method is based on the theory of Parshin's residues and tame symbols on toroidal varieties. It provides a uniform algebraic explanation of the recent result of Khovanskii on the produc

Alexander Teplyaev

Continuous analogs of orthogonal polynomials on the circle are solutions of a canonical system of differential equations, introduced and studied by M.G.Krein and recently generalized to matrix systems by L.A.Sakhnovich. We prove that the continuous analog of the adjoint polynomials converges in the upper half-plane in the case of L^2 coefficients, but in gen

Richard Zach

Quantified propositional intuitionistic logic is obtained from propositional intuitionistic logic by adding quantifiers \forall p, \exists p over propositions. In the context of Kripke semantics, a proposition is a subset of the worlds in a model structure which is upward closed. Kremer (1997) has shown that the quantified propositional intuitionistic logic

Paul S. Aspinwall

The notion of a "point" is essential to describe the topology of spacetime. Despite this, a point probably does not play a particularly distinguished role in any intrinsic formulation of string theory. We discuss one way to try to determine the notion of a point from a worldsheet point of view. The derived category description of D-branes is the key

Jacek Pawelczyk, Harold Steinacker

We propose an algebraic description of (untwisted) D-branes on compact group manifolds $G$ using quantum algebras related to $U_q(\mg)$. It reproduces the known characteristics of stable branes in the WZW models, in particular their configurations in $G$, energies as well as the set of harmonics. Both generic and degenerate branes are covered.

Stoytcho S. Yazadjiev

New nondiagonal $G_{2}$ inhomogeneous cosmological solutions are presented in a wide range of scalar-tensor theories with a stiff perfect fluid as a matter source. The solutions have no big-bang singularity or any other curvature singularities. The dilaton field and the fluid energy density are everywhere regular, too. The geodesic completeness of the soluti

Joseph A. Minahan

In this note, we consider the two derivative truncation of boundary string field theory for unstable D9 branes in Type IIA string theory. We construct multiples of the stable codimension 1 solitons that correspond to stacks of D8 branes. We find the fluctuation modes that correspond to open strings stretching between the branes, and find that their masses ar

Yves Brihaye, Betti Hartmann

We consider the Abelian Higgs model as well as the SU(2) Georgi-Glashow model in which the gauge field action is replaced by a non linear Born-Infeld action. We study soliton solutions arising in these models, namely the vortex and monopole solutions, respectively. We construct formulas which provide good approximations for the mass of the Born-Infeld deform

Ryszard Gabryszewski, Ireneusz Wlodarczyk

Mean motion resonances (MMRs) can lead either to chaotic or regular motion. We report on a numerical experiment showing that even in one of the most chaotic regions of the Solar System - the region of the giant planets, there are numerous bands where MMRs can stabilize orbits of small bodies in a time span comparable to their lifetimes. Two types of temporar

L. Kullmann, J. Kertesz, K. Kaski

We study the time dependent cross correlations of stock returns, i.e. we measure the correlation as the function of the time shift between pairs of stock return time series using tick-by-tick data. We find a weak but significant effect showing that in many cases the maximum correlation is at nonzero time shift indicating directions of influence between the c

Philippe Ruelle

We consider the unoriented two-dimensional Abelian sandpile model on the half-plane with open and closed boundary conditions. We show that the operator effecting the change from closed to open, or from open to closed, is a boundary primary field of weight -1/8, belonging to a c=-2 logarithmic conformal field theory.

S. Jadach

A general purpose, self-adapting, Monte Carlo (MC) event generator (simulator) is described. The high efficiency of the MC, that is small maximum weight or variance of the MC weight is achieved by means of dividing the integration domain into small cells. The cells can be $n$-dimensional simplices, hyperrectangles or Cartesian product of them. The grid of ce

S. Avvakumov, T. Adams, A. Alton, L. deBarbaro

Limits on $ν_μ\to ν_e$ and $\barν_μ\to \barν_e$ oscillations are extracted using the NuTeV detector with sign-selected $ν_μ$ and $\nub_μ$ beams. In $\nub_μ$ mode, for the case of $\sin^2 2α= 1$, $Δm^2 > 2.6$ ${\rm eV^2}$ is excluded, and for $Δm^2 \gg 1000$ ${\rm eV^2}$, $\sin^2 2α> 1.1 \times 10^{-3}$. The NuTeV data exclude the high $Δm^2$ end of $\barν_μ\

David C. Dunbar, Nicolaus W. P. Turner

In this letter we investigate the ultra-violet behaviour of four-point one-loop gluon amplitudes in dimensions greater than four coupled to various particles types. We discuss the structure of the counterterms and their inherent symmetries.

Peter Grassberger, Walter Nadler, Lei Yang

We present large scale simulations for a one-dimensional chain of hard-point particles with alternating masses. We correct several claims in the recent literature based on much smaller simulations. Both for boundary conditions with two heat baths at different temperatures at both ends and from heat current autocorrelations in equilibrium we find heat conduct

Thomas Lippert

Cost estimates for simulations of full QCD with n_f=2 Wilson fermions by hybrid Monte Carlo are presented. The extrapolations are based on the average number of iterations of the iterative solver within the fermionic part of the HMC molecular dynamics, which is closely related to the minimal eigenvalue of M^+M The cost formula is determined as a product of t

Hisayosi Matumoto

We obtain a decomposition formula of a representation of Sp(p,q) and SO^\ast(2n) unitarily induced from a derived functor module, which enables us to reduce the problem of irreducible decompositions to the study of derived functor modules. In particular, we show such an induced representation is decomposed into a direct sum of irreducible unitarily induced m

C. Ferdeghini, V. Braccini, M. R. Cimberle, D. Marre

The anisotropy of MgB2 is still under debate: its value, strongly dependent on the sample and on the measuring method, ranges between 1.2 and 13. In this work we present our results on a MgB2 c-oriented superconducting thin film. To evaluate the anisotropy, we followed two different approaches. Firstly, magnetoresistivity was measured as a function of temper

Hyun-Tak Kim, Kwang-Yong Kang, Eun-Hee Lee

A ferromagnetic phase, characterized by electron carriers and a high temperature colossal magnetoresistance (HTCMR) dependent on the magnetic moment, and a semiconducting phase, characterized by hole carriers and a low temperature CMR (LTCMR), are observed in La$_{1-x}$Ca$_{x}$MnO$_3$ thin films by the van der Pauw method. The LTCMR is much more sensitive to

Kazunori Kohri, Shin Mineshige

It is often considered that a massive torus with solar mass or so surrounding a stellar-mass black hole may be a central engine of a gamma-ray burst. We study the properties of such massive accretion tori (or disks) based on the $α$ viscosity model. For surface density exceeding about $10^{20}$ g cm$^{-2}$, which realizes when about a solar-mass material is

G. S. Agarwal, S. Chaturvedi

We propose a scheme to measure quantum Stokes parameters, their fluctuations and correlations. The proposal involves measurements of intensities and intensity- intensity correlations for suitably defined modes, which can be produced by a combination of half wave and quarter wave plates.

Jack Laiho, Amarjit Soni

We show that lattice calculation of K --> pi pi and $epe$ amplitudes for (8,1) and (27,1) operators to O(p^4) in chiral perturbation theory is feasible when one uses K --> pi pi computations at the two unphysical kinematics allowed by the Maiani-Testa theorem, along with the usual (computable) two and three point functions, namely K --> 0, K --> pi (with mom

Raphael Bousso

There is strong evidence that the area of any surface limits the information content of adjacent spacetime regions, at 10^(69) bits per square meter. We review the developments that have led to the recognition of this entropy bound, placing special emphasis on the quantum properties of black holes. The construction of light-sheets, which associate relevant s

Ganpathy Murthy, Harsh Mathur

Using a fermionic renormalization group approach we analyse a model where the electrons diffusing on a quantum dot interact via Fermi-liquid interactions. Describing the single-particle states by Random Matrix Theory, we find that interactions can induce phase transitions (or crossovers for finite systems) to regimes where fluctuations and collective effects

Fred Cooper, Avinash Khare, Uday Sukhatme

We show that a type of linear superposition principle works for several nonlinear differential equations. Using this approach, we find periodic solutions of the Kadomtsev-Petviashvili (KP) equation, the nonlinear Schrodinger (NLS) equation, the $λϕ^4$ model, the sine-Gordon equation and the Boussinesq equation by making appropriate linear superpositions of k

Paul M. Alsing, Gerard J. Milburn

We study the transformation of maximally entangled states under the action of Lorentz transformations in a fully relativistic setting. By explicit calculation of the Wigner rotation, we describe the relativistic analog of the Bell states as viewed from two inertial frames moving with constant velocity with respect to each other. Though the finite dimensional

Robert Raussendorf, Hans Briegel

In this paper we present the computational model underlying the one-way quantum computer which we introduced recently [Phys. Rev. Lett. 86, 5188 (2001)]. The one-way quantum computer has the property that any quantum logic network can be simulated on it. Conversely, not all ways of quantum information processing that are possible with the one-way quantum com

Marcos Curty, David J. Santos

This paper has been withdrawn by the authors because the results obtained have been reported earlier by other authors.

S. E. Emelin, A. L. Pirozerski

The brief characteristic of a place and state of modern experimental investigations of a ball lightning on the basis of metastable substance is given.

Sen Cheng

Recursion relations are used to exactly calculate the partition function of a canonical ensemble in which all additive charges as well as the total isospin are strictly conserved. The ensemble can consist of particles that obey either classical or quantum statistics. Recursion relations are also employed to compute observables such as multiplicity distributi

W. Cassing, E. L. Bratkovskaya, O. Hansen

The production of antiprotons in $p+A$ reactions is calculated in a microscopic transport approach employing hadronic and string degrees of freedom (HSD). It is found that the abundancies of antiprotons as observed by the E910 Collaboration in $p+A$ reactions at 12.3 GeV/c as well as 17.5 GeV/c can approximately be described on the basis of primary proton-nu