April 2005 arXiv papers — page 6

Robert A. Wittenmyer, William F. Welsh, Jerome A. Orosz, A. B. Schultz

We derive improved system parameters for the HD 209458 system using a model that simultaneously fits both photometric transit and radial velocity observations. The photometry consists of previous Hubble Space Telescope STIS and FGS observations, twelve I-band transits observed between 2001-2003 with the Mt. Laguna Observatory 1m telescope, and six Stromgren

Leonardo P. G. de Assis, Jose A. Helayel-Neto, Ricardo C. Paschoal

We present an N=2-supersymmetric mechanical system whose bosonic sector, with two degrees of freedom, stems from the reduction of an SU(2) Yang-Mills theory with the assumption of spatially homogeneous field configurations and a particular ansatz imposed on the gauge potentials in the dimensional reduction procedure. The Painleve test is adopted to discuss i

T. Belloni, J. Homan, P. Casella, M. van der Klis

We present the results of the timing and color analysis of more than two hundred RXTE/PCA observations of the bright black-hole transient GX 339-4 obtained during its 2002/2003 outburst. The color-intensity evolution of the system, coupled to the properties of its fast time variability, allow the identification of four separate states. Depending on the state

The BABAR Collaboration, B. Aubert

We search for B- ==> \tilde{D0}K- and B- ==> \tilde{D*0}K-, with \tilde{D*0} ==> \tilde{D0}pi0 or \tilde{D*0} ==> \tilde{D0}gamma, and \tilde{D0} ==> K+pi- (and charge conjugates). These final states can be reached through the b==>c transition B- ==> D0(*)K- followed by the doubly CKM-suppressed D0 ==> K+pi-, or the b==>u transition B- ==> D0bar(*)K- followe

Luis A. Anchordoqui, Jonathan L. Feng, Haim Goldberg

Ultra-high energy cosmic rays and neutrinos probe energies far above the weak scale. Their usefulness might appear to be limited by astrophysical uncertainties; however, by simultaneously considering up- and down-going events, one may disentangle particle physics from astrophysics. We show that present data from the AMANDA experiment in the South Pole ice al

Vittorio Gorini, Alexander Kamenshchik, Ugo Moschella, Vincent Pasquier

Flat FRW perfect fluid cosmologies can be reproduced as particular solutions of suitable field theoretical models. Here we investigate the stability of perfect fluid model trajectories with respect to sets of trajectories of the corresponding field models having generic initial conditions. It is shown that the trajectories of barotropic perfect fluid models

Kouichi Takemura

Several results including integral representation of solutions and Hermite-Krichever Ansatz on Heun's equation are generalized to a certain class of Fuchsian differential equations, and they are applied to equations which are related with physics. We investigate linear differential equations that produce Painlevé equation by monodromy preserving deformat

Christoly Biely, Klaus Dragosits, Stefan Thurner

We consider the prisoner's dilemma being played repeatedly on a dynamic network, where agents may choose their actions as well as their co-players. This leads to co-evolution of network structure and strategy patterns of the players. Individual decisions are made fully rationally and are based on local information only. They are made such that links to d

Yoshiaki Susaki, Yastoshi Takayama, Kentaroh Yoshida

We further study the correspondence between open semiclassical strings and long defect operators which is discussed in our previous work [hep-th/0410139]. We give an interpretation of the spontaneous symmetry breaking of SO(6)-> SO(3)_H x SO(3)_V from the viewpoint of the Riemann surface by following the argument of Minahan. Then we use the concrete form of

E. Di Grezia, S. Esposito, G. Salesi

Quantitative bounds on Lorentz symmetry violation in the neutrino sector have been obtained by analyzing existing laboratory data on neutron $β$ decay and pion leptonic decays. In particular some parameters appearing in the energy-momentum dispersion relations for $ν_e$ and $ν_μ$ have been constrained in two typical cases arising in many models accounting fo

Christian S. Fischer, Daniel Zwanziger

We consider the class of gauges that interpolates between Landau- and Coulomb-gauge QCD, and show the non-renormalisation of the two independent ghost-gluon vertices. This implies the existence of two RG-invariant running couplings, one of which is interpreted as an RG-invariant gauge parameter. We also present the asymptotic infrared limit of solutions of t

Victor Guillemin, Reyer Sjamaar

Atiyah proved that the moment map image of the closure of an orbit of a complex torus action is convex. Brion generalized this result to actions of a complex reductive group. We extend their results to actions of a maximal solvable subgroup.

Gabriel Sellier, Thilo Kopp, Johann Kroha, Yuri S. Barash

We investigate the temperature- and coupling-dependent transport through Kondo dot contacts with symmetric superconducting s-wave leads. For finite temperature T we use a superconducting extension of a selfconsistent auxiliary boson scheme, termed SNCA, while at T=0 a perturbative renormalization group treatment is applied. The finite-temperature phase diagr

Rik J. Williams, Smita Mathur, Fabrizio Nicastro, Martin Elvis

We report the detection of highly-ionized gas at z~0 seen in resonant UV and X-ray absorption lines toward the z=0.03 blazar Mkn 421. A total of 13 X-ray and 3 UV lines were measured (or upper limits derived), including three lines in the OVII K-series and Kαtransitions from neon, carbon, and nitrogen. From the three OVII lines we derive a 2σDoppler paramete

Stefano Bertolini, Michal Malinsky

We investigate the role of CP phases within the renormalizable SUSY SO(10) GUT with one 10_H, one 126bar_H one 126_H and one 210_H Higgs representations and type II seesaw dominating the neutrino mass matrix. This framework is non trivially predictive in the fermionic sector and connects in a natural way the GUT unification of b and tau Yukawa couplings with

Bert Schroer

In the past two-dimensional models of QFT have served as theoretical laboratories for testing new concepts under mathematically controllable condition. In more recent times low-dimensional models (e.g. chiral models, factorizing models) often have been treated by special recipes in a way which sometimes led to a loss of unity of QFT. In the present work I tr

B. G. Giraud, A. Weiguny, L. Wilets

Special bases of orthogonal polynomials are defined, that are suited to expansions of density and potential perturbations under strict particle number conservation. Particle-hole expansions of the density response to an arbitrary perturbation by an external field can be inverted to generate a mapping between density and potential. Information is obtained for

Hsiao-Ping Hsu, Peter Grassberger

We present high statistics simulations of weighted lattice bond animals and lattice trees on the square lattice, with fugacities for each non-bonded contact and for each bond between two neighbouring monomers. The simulations are performed using a newly developed sequential sampling method with resampling, very similar to the pruned-enriched Rosenbluth metho

J. Kaupuzs, R. Mahnke, R. J. Harris

A multi--cluster model of traffic flow is studied, in which the motion of cars is described by a stochastic master equation. Assuming that the escape rate from a cluster depends only on the cluster size, the dynamics of the model is directly mapped to the mathematically well-studied zero-range process. Knowledge of the asymptotic behaviour of the transition

S. N. Dorogovtsev, J. F. F. Mendes, J. G. Oliveira

The distribution of numbers in human documents is determined by a variety of diverse natural and human factors, whose relative significance can be evaluated by studying the numbers' frequency of occurrence. Although it has been studied since the 1880's, this subject remains poorly understood. Here, we obtain the detailed statistics of numbers in the

L. P. Kaptari, B. Kampfer

Invariant mass spectra of di-electrons stemming from bremsstrahlung processes are calculated in a covariant diagrammatical approach for the exclusive reaction D p \to p_{\rm sp} n p e^+ e^- with detection of a forward spectator proton, p_{sp}. We employ an effective nucleon-meson theory for parameterizing the sub-reaction n p \to n p e^+ e^- and, within the

Ralf Holtkamp

The operad Lie can be constructed as the operad of primitives Prim As from the operad As of associative algebras. This is reflected by the theorems of Friedrichs, Poincare'-Birkhoff-Witt and Cartier-Milnor-Moore. We replace As by families of free operads P, which include the operad Mag freely generated by a noncommutative non-associative binary operation

Tomi Koivisto

We consider the evolution of linear perturbations in models with a nonminimal coupling between dark matter and scalar field dark energy. Growth of matter inhomogeneities in two examples of such models proposed in the literature are investigated in detail. Both of these models are based on a low-energy limit of effective string theory action, and have been pr

R. N. Mohapatra, M. K. Parida, G. Rajasekaran

Radiative corrections to neutrino mixings in seesaw models depend on the nature of new physics between the weak and the GUT-seesaw scales and can be taken into account using the renormalization group equations. This new physics effect becomes particularly important for models with quasi-degenerate neutrino masses where small neutrino mixings at the seesaw sc

Mei Huang

It is found that, except chromomagnetic instability, the gapless 2SC phase also exhibits a paramagnetic response to the perturbation of an external color neutral baryon current. The spontaneously generated baryon current driven by the mismatch is equivalent to the one-plane wave LOFF state. We describe the 2SC phase in the nonlinear realization framework, an

The Belle Collaboration, A. Limosani

We report measurements of partial branching fractions of inclusive charmless semileptonic $B$-meson decays at the endpoint of the electron momentum spectrum. The measurements are made in six overlapping momentum intervals that have lower bounds ranging from 1.9 GeV/$c$ to 2.4 GeV/$c$ and a common upper bound of 2.6 GeV/$c$, as measured in the centre of mass

T. Mizushima, K. Machida, M. Ichioka

We find theoretically that the vortex core in the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state is quite different from the ordinary core by a simple topological reason. The intersection point of a vortex and nodal plane of the FFLO state empties the excess spins. This leads to observable consequences in the spatial structure of the spontaneous magnetization

J. I. Illana, M. Masip, D. Meloni

Cosmogenic neutrinos reach the Earth with energies around 10^9 GeV, and their interactions with matter will be measured in upcoming experiments (Auger, IceCube). Models with extra dimensions and the fundamental scale at the TeV could imply signals in these experiments. In particular, the production of microscopic black holes by cosmogenic neutrinos has been

A. Carrington, J. D. Fletcher, J. R. Cooper, O. J. Taylor

We report a de Haas-van Alphen (dHvA) study of the electronic structure of Al doped crystals of MgB$_2$. We have measured crystals with $\sim 7.5$% Al which have a $T_c$ of 33.6 K, ($\sim 14$% lower than pure MgB$_2$). dHvA frequencies for the $σ$ tube orbits in the doped samples are lower than in pure MgB$_2$, implying a $16\pm2%$ reduction in the number of

D. Schmalfuß, J. Richter, D. Ihle

We consider the thermodynamic properties of the quasi-two-dimensional spin-half Heisenberg ferromagnet on the stacked square and the stacked kagomé lattices by using the spin-rotation-invariant Green's function method. We calculate the critical temperature $T_C$, the uniform static susceptibility $χ$, the correlation lengths $ξ_ν$ and the magnetization $

D. S. Saraga, Daniel Loss

We derive analytical expressions for the quasiparticle lifetime tau, the effective mass m*, and the Green's function renormalization factor Z for a 2D Fermi liquid with electron-electron interaction in the presence of the Rashba spin-orbit interaction. We find that the modifications are independent of the Rashba band index rho, and occur in second order

Maxim Pospelov, Adam Ritz

We review several aspects of flavour-diagonal CP violation, focussing on the role played by the electric dipole moments (EDMs) of leptons, nucleons, atoms and molecules, which consitute the source of several stringent constraints on new CP-violating physics. We dwell specifically on the calculational aspects of applying the hadronic EDM constraints, reviewin

The DIRAC collaboration

The goal of the DIRAC experiment at CERN (PS212) is to measure the $π^+π^-$ atom lifetime with 10% precision. Such a measurement would yield a precision of 5% on the value of the $S$-wave $ππ$ scattering lengths combination $|a_0-a_2|$. Based on part of the collected data we present a first result on the lifetime, $τ=[2.91 ^{+0.49}_{-0.62}]\times 10^{-15}$ s

P. Jiji Thomas Joseph, Prabhakar P. Singh

The influence of vacancies in the $C$ sub-lattice of $MgCNi_{3}$, on its structural, electronic and magnetic properties are studied by means of the density-functional based Korringa-Kohn-Rostoker Green's function method formulated in the atomic sphere approximation. Disorder is taken into account by means of coherent-potential approximation. Characteriza

M. Allalen, J. Schnack

Heterometallic molecular chromium wheels are fascinating new magnetic materials. We reexamine the available experimental susceptibility data on MCr7 wheels in terms of a simple isotropic Heisenberg Hamiltonian for M=Fe, Ni, Cu, and Zn and find in that FeCr7 needs to be described with an iron-chromium exchange that is different from all other cases. In a seco

Ali Kaya

In a toy model with gases of membranes and strings wrapping over a two-dimensional internal torus, we study the stabilization problem for the shape modulus. It is observed that winding modes of partially wrapped strings and momentum modes give rise to stress in the energy momentum tensor. We show that this stress dynamically stabilizes the shape modulus of t

Sanjeev Kumar, Pinaki Majumdar

We study a tight binding model including both on site disorder and coupling of the electrons to randomly oriented magnetic moments. The transport properties are calculated via the Kubo-Greenwood scheme, using the exact eigenstates of the disordered system and large system size extrapolation of the low frequency optical conductivity. We first benchmark our me

Ashok Prasad, Yuko Hori, Jane' Kondev

We study theoretically the entropic elasticity of a semi-flexible polymer, such as DNA, confined to two dimensions. Using the worm-like-chain model we obtain an exact analytical expression for the partition function of the polymer pulled at one end with a constant force. The force-extension relation for the polymer is computed in the long chain limit in term

G. Lugones, I. Bombaci

We study the deconfinement transition of hadronic matter into quark matter in neutron star conditions in the light of color superconductivity. Deconfinement is considered to be a first order phase transition that conserves color and flavor. It gives a short-lived {($τ\sim τ_{weak}$)} transitory colorless-quark-phase that is {\it not} in $β$-equilibrium. We d

Igor Rozhkov, Ganpathy Murthy

A variety of mesoscopic systems can be represented as a billiard with a random coupling to the exterior at the boundary. Examples include quantum dots with multiple leads, quantum corrals with different kinds of atoms forming the boundary, and optical cavities with random surface refractive index. The specific example we study is a circular (integrable) bill

Stephen Fairhurst, Hirotaka Takahashi

We present the status of the joint search for gravitational waves from inspiraling neutron star binaries in the LIGO Science Run 2 and TAMA300 Data Taking Run 8 data, which was taken from February 14 to April 14, 2003, by the LIGO and TAMA collaborations. In this paper we discuss what has been learned from an analysis of a subset of the data sample reserved

Bradley Hagan, Chung-Pei Ma, Andrey V. Kravtsov

We explore the effect of substructure in dark matter halos on the power spectrum and bispectrum of matter fluctuations and weak lensing shear. By experimenting with substructure in a cosmological N = 512^3 simulation, we find that when a larger fraction of the host halo mass is in subhalos, the resulting power spectrum has less power at 1 < k < 100 h Mpc^{-1

Qing-Hong Cao, Reinhard Schwienhorst, Jorge A. Benitez, Raymond Brock

We present a study of the $t$-channel mode of single top quark production at the upgraded Tevatron $p\bar{p}$ collider, including the next-to-leading order (NLO) QCD corrections to the production and the decay of a single top quark. The narrow width approximation was adopted in order to preserve the spin of the top quark in its production and decay. We discu

Alejandro Corichi, Ulises Nucamendi, Marcelo Salgado

The Isolated Horizons (IH) formalism, together with a simple phenomenological model for colored black holes has been used to predict non-trivial formulae that relate the ADM mass of the solitons and hairy Black Holes of Gravity-Matter system on the one hand, and several horizon properties of the black holes in the other. In this article, the IH formalism is

Wontae Kim, Young-Jai Park, Edwin J. Son, Myung Seok Yoon

We study ``draining bathtub&#39;&#39; as an acoustic analogue of a three-dimensional rotating black hole. Rotating fluid near the sonic horizon necessarily gives rise to the superradiant modes, which are partially responsible for the thermodynamic quantities in this rotating vortex-like hole. Using the recently suggested thin-layer method overcoming some dif

Shizuka Akiyama, J. Craig Wheeler

Traditional models of core collapse suggest the issue of successful versus failed supernova explosions and neutron star versus black hole formation depends monotonically on the mass (and metallicity) of the progenitor star. Here we argue that the issue of success or failure of the explosion or other possible outcomes may depend non--monotonically on the rota

Janos Bergou, Mark Hillery

We construct a device that can unambiguously discriminate between two unknown quantum states. The unknown states are provided as inputs, or programs, for the program registers and a third system, which is guaranteed to be prepared in one of the states stored in the program registers, is fed into the data register of the device. The device will then, with som

Jean Schneider

I show that the quantum measurement problem can be understood if the measurement is seen as a ``speech act&#39;&#39; in the sense of modern language theory. The reduction of the state vector is in this perspective an intersubjectice -- or better a-subjective -- symbolic process. I then give some perspectives on applications to the ``Mind-Body problem&#39;&#3

Alastair Kay

Recent studies of globally controlled structures have culminated in a theoretical demonstration that fault-tolerant quantum computation can be carried out on a one--dimensional chain with control over two global fields only. This required some patterns of classical states to localise operations, which were stabilised with the Zeno effect. However, it is impo

Marco Genovese

In this paper we present the results of numerical calculations about the minimal value of detection efficiency for violating the Clauser - Horne inequality for qutrits. Our results show how the use of non-maximally entangled states largely improves this limit respect to maximally entangled ones. A stronger resistance to noise is also found.

A. Papageorgiou, H. Wozniakowski

We show how a number of NP-complete as well as NP-hard problems can be reduced to the Sturm-Liouville eigenvalue problem in the quantum setting with queries. We consider power queries which are derived from the propagator of a system evolving with a Hamiltonian obtained from the discretization of the Sturm-Liouville operator. We show that the number of power

Le Van Hoang, Nguyen Thanh Son

The Hurwits transformation is generalized by introducing three new variables called &#39;extra&#39;. Interpretation of these extra variables allows us to establish relation between isotropic harmonic oscillator and five-dimensional hydrogen-like atom in &#39;electromagnetic&#39; fields of various configurations. For the Schrodinger equations, the scheme of s

Kurt Jacobs, Howard Wiseman

Non-locality of the type first elucidated by Bell in 1964 is a difficult concept to explain to non-specialists and undergraduates. Here we attempt this by showing how such non-locality can be used to solve a problem in which someone might find themselves as the result of a collection of normal, even if somewhat unlikely, events. Our story is told in the styl

Guruprasad Kar

John Bell taught us that quantum mechanics can not be reproduced by non-contextual and local Hidden variable theory. The impossibility of replacing quantum mechanics by non-contextual Hidden Variable Theory can be turned to a impossible coloring pseudo-telepathy game to be played by two distant players. The game can not be won without communication in the cl

Samir Kunkri, Sujit K. Choudhary

We analyze Hardy&#39;s non-locality argument for two spin-s systems and show that earlier solution in this regard was restricted due to imposition of some conditions which have no role in the argument of non-locality. We provide a compact form of non-locality condition for two spin-s systems and extend it to n number of spin-s particles. We also apply more g

Sven Aerts

A black box with two input bits and two output bits is called a non-local PR box, if the XOR of the output bits equals the AND of the input bits. In a recent article, Cerf et al. show that Alice and Bob, using such a PR box, can effectively simulate entanglement without the need of communication. We show that an adaptation of a model due to Dirk Aerts, yield

Dave Bacon, Andrew M. Childs, Wim van Dam

We approach the hidden subgroup problem by performing the so-called pretty good measurement on hidden subgroup states. For various groups that can be expressed as the semidirect product of an abelian group and a cyclic group, we show that the pretty good measurement is optimal and that its probability of success and unitary implementation are closely related

V. Eisler, Z. Zimboras

We consider the ground state of the XX chain that is constrained to carry a current of energy. The von Neumann entropy of a block of $L$ neighboring spins, describing entanglement of the block with the rest of the chain, is computed. Recent calculations have revealed that the entropy in the XX model diverges logarithmically with the size of the subsystem. We

Netanel H. Lindner, Daniel R. Terno

When a photon with well-defined polarization and momentum passes through a focusing device, these properties are no longer well defined. Their loss is captured by describing polarization by a 3x3 effective density matrix. Here we show that the effective density matrix corresponds to the actual photodetection model and we provide a simple formula to calculate

Azi Lipshtat, Hagai B. Perets, Nathalie Q. Balaban, Ofer Biham

We discuss recent developments in the modeling of negative autoregulated genetic networks. In particular, we consider the temporal evolution of the population of mRNA and proteins in simple networks using rate equations. In the limit of low copy numbers, fluctuation effects become significant and more adequate modeling is then achieved using the master equat

Gordon Chalmers

A scheme is presented based on numbers that represent a manifold in $d$ dimensions for generalizations of textbook cryptosystems. The interlocking or intersection of geometries, requiring the addition of a series of integers $q_j$, can be used to enhance a cryptosystem via algorithms based on the form of the geometry. Further operations besides addition of t

Dirk Helbing, Martin Schonhof, Hans-Ulrich Stark, Janusz A. Holyst

In many social dilemmas, individuals tend to generate a situation with low payoffs instead of a system optimum (&#34;tragedy of the commons&#34;). Is the routing of traffic a similar problem? In order to address this question, we present experimental results on humans playing a route choice game in a computer laboratory, which allow one to study decision beh

Gordon Chalmers

The polytopic definition introduced recently describing the topology of manifolds is used to formulate a generating function pertinent to its topological properties. In particular, a polynomial in terms of one variable and a tori underlying this polynomial may be defined that generates an individual cohomological count. This includes the de Rham complex for

Alexandros Leontitsis, Constantinos E. Vorlow

Surrogate Data Analysis (SDA) is a statistical hypothesis testing framework for the determination of weak chaos in time series dynamics. Existing SDA procedures do not account properly for the rich structures observed in stock return sequences, attributed to the presence of heteroscedasticity, seasonal effects and outliers. In this paper we suggest a modific

Klaus L. Gottstein

Scientists as diplomats (historical examples). Scientists as advisors to governments and the public. Nongovernmental organisations and international conferences on security questions, initiated by scientists and based on their professional culture.

A. Buzulutskov, J. Dodd, R. Galea, Y. Ju

We study the performance of Gas Electron Multipliers (GEMs) in gaseous He, Ne and Ne+H2 at temperatures in the range of 2.6-293 K. In He, at temperatures between 62 and 293 K, the triple-GEM structures often operate at rather high gains, exceeding 1000. There is an indication that this high gain is achieved by Penning effect in the gas impurities released by

A. I. Milstein, V. M. Strakhovenko

Kinetics of the polarization buildup at the interaction of stored protons (antiprotons) with a polarized target is considered. It is demonstrated that for small scattering angles, when a projectile remains in the beam, the polarization buildup is completely due to the spin-flip transitions. The corresponding cross sections turn out to be negligibly small for

E. C. Le Ru, P. G. Etchegoin

We discuss the effect of the local field polarization in metallic nanostructures where large field enhancements can be induced by excitation of localized surface plasmons. To demonstrate the importance of these effects, we study a few model systems in 2D and 3D. As an experimental probe of this effect, we suggest to use depolarization ratios in Surface Enhan

A. O. Sushkov, E. Williams, D. Budker

The transmission characteristics of commercial interference filters are not quite what we expected from the specifications provided by manufacturers. The unexpectedly sharp dependences of the transmission coefficient on the incidence angle, wavelength, and on the position where the light beam falls on the filter may be important in the analysis of systematic

L. Coraggio, N. Itaco

First self-consistent realistic shell-model calculation for the light p-shell nuclei is performed, starting from the high-precision nucleon-nucleon (NN) CD-Bonn potential. This realistic potential is renormalized deriving a low-momentum NN potential V-low-k that preserves exactly the two-nucleon low-energy physics. This V-low-k is suitable to derive a self-c

A. Titov, B. Kampfer

We analyze two types of spin observables in the reaction $π\vec D\to\vecΣΘ^+$ near the threshold. One concerns the spin-transfer coefficients $K_x^x$ and $K_z^z$. The second one is the deuteron spin anisotropy. These observables are sensitive to the $Θ^+$ parity and can be used as a tool for the $Θ^+$ parity determination.

J. F. Liang, C. Signorini

The use of radioactive beams opens a new frontier for fusion studies. The coupling to the continuum can be explored with very loosely bound nuclei. Experiments were performed with beams of nuclei at or near the proton and neutron drip-lines to measure fusion and associated reactions in the vicinity of the Coulomb barrier. In addition, the fusion yield is pre

R. S Hicks, P. Decowski, C. Arroyo, M. Breuer

The paper describes the design and performance of flux integrating Cherenkov scanners with air-core reflecting light guides used in a high-energy, high-flux electron scattering experiment at the Stanford Linear Accelerator Center. The scanners were highly radiation resistant and provided a good signal to background ratio leading to very good spatial resoluti

Yoshimasa Matsuno

The parametric representation is given to the multisoliton solution of the Camassa-Holm equation. It has a simple structure expressed in terms of determinants. The proof of the solution is carried out by an elementary theory of determinanats. The large time asymptotic of the solution is derived with the fomula for the phase shift. The latter reveals a new fe

Derin B. Wysham, James D. Meiss

We develop an iterative technique for computing the unstable and stable eigenfunctions of the invariant tori of diffeomorphisms. Using the approach of Jorba, the linearized equations are rewritten as a generalized eigenvalue problem. Casting the system in this light allows us to take advantage of the speed of eigenvalue solvers and create an efficient method

Ian M. Musson

Let $H_{\mathbf{k}}$ be a symplectic reflection algebra corresponding to a cyclic subgroup $Γ\subseteq SL_2 \C$ of order $n$ and $U_{\mathbf{k}} = eH_{\mathbf{k}} e$ the spherical subalgebra of $H_{\mathbf{k}}$. We show that for suitable ${\mathbf{k}}$ there is a filtered $\Z^{n-1}$-algebra $R$ such that (1) there is an equivalence of categories $R-\mathrm{q

Elise Fouassier

We derive the high frequency limit of the Helmholtz equation with source term when the source is the sum of two point sources. We study it in terms of Wigner measures (quadratic observables). We prove that the Wigner measure associated with the solution satisfies a Liouville equation with, as source term, the sum of the source terms that would be created by

Harish Seshadri

We give lower bounds, in terms of the Euler characteristic, for the $L^2$-norm of the Weyl curvature of closed Riemannian 4-manifolds. The same bounds were obtained by Gursky, in the case of positive scalar curvature metrics.

Erik I. Broman, Olle Haggstrom, Jeffrey E. Steif

In a recent paper by two of the authors, the concepts of upwards and downwards $ε$-movability were introduced, mainly as a technical tool for studying dynamical percolation of interacting particle systems. In this paper, we further explore these concepts which can be seen as refinements or quantifications of stochastic domination, and we relate them to previ

Thomas Liggett, Jeffrey E. Steif

We prove for the contact process on $Z^d$, and many other graphs, that the upper invariant measure dominates a homogeneous product measure with large density if the infection rate $λ$ is sufficiently large. As a consequence, this measure percolates if the corresponding product measure percolates. We raise the question of whether domination holds in the symme

Satoshi Murai

A Gotzmann monomial ideal of the polynomial ring is a monomial ideal which is generated in one degree and which satisfies Gotzmann&#39;s persistence theorem. A subset $V$ is said to be a Gotzmann subset if the ideal generated by $V$ is a Gotzmann monomial ideal. In the present paper, we find all integers $a>0$ such that every Gotzmann subset $V$ with $|V|=a$

Xianzhe Dai, Xiaodong Wang, Guofang Wei

Using spin$^c$ structure we prove that Kähler-Einstein metrics with nonpositive scalar curvature are stable (in the direction of changes in conformal structures) as the critical points of the total scalar curvature functional. Moreover if all infinitesimal complex deformation of the complex structure are integrable, then the Kähler-Einstein metric is a local

Adam Piggott

The centrepiece of this paper is a normal form for primitive elements which facilitates the use of induction arguments to prove properties of primitive elements. The normal form arises from an elementary algorithm for constructing a primitive element p in F(x, y) with a given exponent sum pair (X, Y), if such an element p exists. Several results concerning t

Abel Castorena

The paper has been withdrawn by change of content and some errors in the examples.

Genkai Zhang

Let $R$ be a root system of type BC in $\mathfrak a=\mathbb R^r$ of general positive multiplicity. We introduce certain canonical weight function on $\mathbb R^r$ which in the case of symmetric domains corresponds to the integral kernel of the Berezin transform. We compute its spherical transform and prove certain Bernstein-Sato type formula. This generalize

Andrei Okounkov, Nicolai Reshetikhin

We study random skew 3D partitions weighted by $q^{\textup{vol}}$ and, specifically, the $q\to 1$ asymptotics of local correlations near various points of the limit shape. We obtain sine-kernel asymptotics for correlations in the bulk of the disordered region, Airy kernel asymptotics near a general point of the frozen boundary, and a Pearcey kernel asymptoti

Huaxin Lin

Let X be an infinite compact metric space with finite covering dimension. Let $\afhpa,\bt: X\to X$ be two minimal homeomorphisms. Suppose that the range of $K_0$-groups of both crossed product C*-algebras s are dense in the space of real affine continuous functions. We show that $\af$ and $\bt$ are approximately conjugate uniformly in measure if and only if

Philippe Caldero, Frederic Chapoton

Recent articles have shown the connection between representation theory of quivers and the theory of cluster algebras. In this article, we prove that some cluster algebras of type ADE can be recovered from the data of the corresponding quiver representation category. This also provides some explicit formulas for cluster variables.

Shouchuan Zhang, Bizhong Yang, Beishang Ren

An example of double cross coproducts with both non-trivial left coaction and non-trivial right coaction in strictly braided tensor categories is given.

Remke Kloosterman, Orsola Tommasi

In this paper we describe some geometrical properties of the Weierstrass scheme of locally trivial hyperelliptic fibrations.

Fuquan Fang

Let M be a positive quaternionic Kaehler manifold of dimension 4m. If the isometry group Isom(M) has rank at least m/2 +3, then M is isometric to HP^m or Gr_2(C^{m+2}). The lower bound for the rank is optimal if m is even.

Francois Labourie

In 1990, Hitchin&#39;s proved a component of the space of representations of a surface group in SL(n,R) is homeomorphic to a ball. For n=2,3 this component has been identified with the holonomies of geometric structures (hyperbolic for n=2, or real projective for n=3). In the preprint &#34;Anosov flows, Surface groups and Curves in Projective Space&#34;, we

Z. Kuznetsova, Z. Popowicz, F. Toppan

The $n\to\infty$ continuum limit of super-Toda models associated with the affine $sl(2n|2n)^{(1)}$ (super)algebra series produces $(2+1)$-dimensional integrable equations in the ${\bf S}^{1}\times {\bf R}^2$ spacetimes. The equations of motion of the (super)Toda hierarchies depend not only on the chosen (super)algebras but also on the specific presentation o

Le Van Hoang, Nguyen Thanh Son

The scheme of isospin separation is suggested for the equation describing the five-dimensional &#39;charge-dyon&#39; system in a non-Abelian SU(2) model. As a result, we obtain the Schrodinger equation for &#39;bare&#39; particle, moving in Coulomb potential plus potential of five-dimensional Dirac monopole.

Michael Flohr, Marco Krohn

The generic structure of 4-point functions of fields residing in indecomposable representations of arbitrary rank is given. The used algorithm is described and we present all results for Jordan-rank $r=2$ and $r=3$ where we make use of permutation symmetry and use a graphical representation for the results. A number of remaining degrees of freedom which can

Yu. M. Zinoviev

In this paper we consider a possibility to construct dual formulation of gravity where the main dynamical field is the Lorentz connection ω_μ^{ab} and not that of tetrad e_μ^a or metric g_μν. Our approach is based on the usual dualization procedure which uses first order parent Lagrangians but in (Anti) de Sitter space and not in the flat Minkowski one. It t

Robert C. Helling

The dynamics of a stack of N D-branes is described by U(N) gauge theory of which the central U(1) describes the center of mass motion and the remaining SU(N) describes the internal dynamics. In the non-commutative situation, these two parts are coupled by the *-commutator interaction. We describe here how to identify the correct decoupled U(1) center of mass

A. N. Sissakian, A. V. Tarasov, H. T. Torosyan, O. O. Voskresenskaya

We investigate the structure of some first terms of Watson series representing the amplitude of lepton-pair production in the ion collisions. It is shown that infrared instabilities of individual terms trend to cancel each other providing the infrared stability of whole amplitude.

M. V. Chizhov, S. T. Petcov

We have found in [1] new conditions for a total neutrino conversion in the case of neutrino oscillations taking place in a medium, consisting of n = 2 (or 3) alternating layers with constant densities $N_1$ and $N_2$. It is claimed in [4] that our results are particular case of enhancement of neutrino oscillations, which was suggested earlier by other author

Yasunori Nomura, Brock Tweedie

A general framework is presented for supersymmetric theories that do not suffer from fine-tuning in electroweak symmetry breaking. Supersymmetry is dynamically broken at a scale Λ\approx (10 - 100) TeV, which is transmitted to the supersymmetric standard model sector through standard model gauge interactions. The dynamical supersymmetry breaking sector posse