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April 2009 arXiv papers — page 46

Showing 4,5014,600 of 4,924 papers

  1. Matthew Daws

    Let $G$ be a locally compact group, and consider the weakly-almost periodic functionals on $M(G)$, the measure algebra of $G$, denoted by $\wap(M(G))$. This is a C$^*$-subalgebra of the commutative C$^*$-algebra $M(G)^*$, and so has character space, say $K_\wap$. In this paper, we investigate properties of $K_\wap$. We present a short proof that $K_\wap$ can

  2. David Gerard-Varet, Emmanuel Dormy

    The concern of this paper is the Cauchy problem for the Prandtl equation. This problem is known to be well-posed for analytic data, or for data with monotonicity properties. We prove here that it is linearly ill-posed in Sobolev type spaces. The key of the analysis is the construction, at high tangential frequencies, of unstable quasimodes for the linearizat

  3. Jose Beltran Jimenez, Ruth Lazkoz, Antonio L. Maroto

    It has been recently shown that the presence of a vector field over cosmological scales could explain the observed accelerated expansion of the universe without introducing neither new scales nor unnatural initial conditions in the early universe, thus avoiding the coincidence problem. Here, we present a detailed analysis of the constraints imposed by SNIa,

  4. Tom Bohman, Alan Frieze

    Let G_{\rm 3-out} denote the random graph on vertex set [n] in which each vertex chooses 3 neighbors uniformly at random. Note that G_{\rm 3-out} has minimum degree 3 and average degree 6. We prove that the probability that G_{\rm 3-out} is Hamiltonian goes to 1 as n tends to infinity.

  5. Elmar Diederichs, Anatoli Juditsky, Vladimir Spokoiny, Christof Schuette

    Non-gaussian component analysis (NGCA) introduced in offered a method for high dimensional data analysis allowing for identifying a low-dimensional non-Gaussian component of the whole distribution in an iterative and structure adaptive way. An important step of the NGCA procedure is identification of the non-Gaussian subspace using Principle Component Analys

  6. Ewald Puchwein, Stefan Hilbert

    We use ray-tracing through the Millennium simulation to study how secondary matter structures along the line-of-sight and the stellar mass in galaxies affect strong cluster lensing, in particular the cross-section for giant arcs. Furthermore, we investigate the distribution of the cluster Einstein radii and the radial distribution of giant arcs. We find that

  7. Laurent Ponson, Nicholas Boechler, Yi Ming Lai, Mason A. Porter

    We investigate the propagation and scattering of highly nonlinear waves in disordered granular chains composed of diatomic (two-mass) units of spheres that interact via Hertzian contact. Using ideas from statistical mechanics, we consider each diatomic unit to be a "spin", so that a granular chain can be viewed as a spin chain composed of units that

  8. Diogo R. Boito, Rafel Escribano, Matthias Jamin

    Recently, we introduced several dispersive representations for the vector $K\pi$ form factor and fitted them to the Belle spectrum of $\tau \to K \pi \nu_\tau$. Here, we briefly present the model and discuss the results for the slope and curvature of $F_+(s)$ arising from the best fit. Furthermore, we compare the pole position of the charged $K^*(892)$ compu

  9. Michael Zwolak, H. T. Quan, Wojciech H. Zurek

    Quantum Darwinism recognizes that we - the observers - acquire our information about the "systems of interest" indirectly from their imprints on the environment. Here, we show that information about a system can be acquired from a mixed-state, or hazy, environment, but the storage capacity of an environment fragment is suppressed by its initial entro

  10. Kirill Krasnov

    We give a pedagogical introduction into an old, but unfortunately not commonly known formulation of GR in terms of self-dual two-forms due to in particular Jerzy Plebanski. Our presentation is rather explicit in that we show how the familiar textbook solutions: Schwarzschild, Volkoff-Oppenheimer, as well as those describing the Newtonian limit, a gravitation

  11. Paul H. Frampton, Thomas W. Kephart, Ryan M. Rohm

    A nonabelian finite flavor group $G \subset SO(3)$ can have double covering $G^{'} \subset SU(2)$ such that $G \not\subset G^{'}$. This situation is not contradictory, but quite natural, and we give explicit examples such as $G=D_n, G^{'}=Q_{2n}$ and $G=T, G^{'}=T^{'}$. This observation can be crucial in particle theory model building.

  12. Jasmin Raissy

    Let $f$ be a germ of biholomorphism of $\C^n$, fixing the origin. We show that if the germ commutes with a torus action, then we get information on the germs that can be conjugated to $f$, and furthermore on the existence of a holomorphic linearization or of a holomorphic normalization of $f$. We find out in a complete and computable manner what kind of stru

  13. J. von Stecher, E. Demler, M. D. Lukin, A. M. Rey

    We propose a controllable method for observing interaction induced ferromagnetism in ultracold fermionic atoms loaded in optical superlattices. We first discuss how to probe and control Nagaoka ferromagnetism in an array of isolated plaquettes (four lattice sites arranged in a square). Next, we show that introducing a weak interplaquette coupling destroys th

  14. Werner Vogelsang, Feng Yuan

    We calculate the next-to-leading order perturbative QCD corrections to the transverse momentum weighted single transverse spin asymmetry in Drell-Yan lepton pair production in hadronic collisions. We identify the splitting function relevant for the scale evolution of the twist-three quark-gluon correlation function. We comment on the consequences of our resu

  15. Adam M. Goyt, David Mathisen

    In a recent paper, Goyt and Sagan studied distributions of certain set partition statistics over pattern restricted sets of set partitions that were counted by the Fibonacci numbers. Their study produced a class of $q$-Fibonacci numbers, which they related to $q$-Fibonacci numbers studied by Carlitz and Cigler. In this paper we will study the distributions o

  16. Jesus Guillera

    The known WZ-proofs for Ramanujan-type series related to $1/\pi$ gave us the insight to develop a new proof strategy based on the WZ-method. Using this approach we are able to find more generalizations and discover first WZ-proofs for certain series of this type.

  17. Plamen P. Fiziev

    The present article reveals important properties of the confluent Heun's functions. We derive a set of novel relations for confluent Heun's functions and their derivatives of arbitrary order. Specific new subclasses of confluent Heun's functions are introduced and studied. A new alternative derivation of confluent Heun's polynomials is presen

  18. G. Bernardi, A. G. de Bruyn, M. A. Brentjens, B. Ciardi

    We present the first results from a series of observations conducted with the Westerbork telescope in the 140--160 MHz range with a 2 arcmin resolution aimed at characterizing the properties of the foregrounds for epoch of reionization experiments. For the first time we have detected fluctuations in the Galactic diffuse emission on scales greater than 13 arc

  19. A. Hart, G. M. von Hippel, R. R. Horgan, E. H. Müller

    The derivation of the Feynman rules for lattice perturbation theory from actions and operators is complicated, especially for highly improved actions such as HISQ. This task is, however, both important and particularly suitable for automation. We describe a suite of software to generate and evaluate Feynman rules for a wide range of lattice field theories wi

  20. Yan Liu, Ya-Wen Sun

    In this note we investigate the generalized massive gravity in asymptotically $AdS_3$ spacetime by combining the two mass terms of topological massive gravity and new massive gravity theory. We study the linearized excitations around the $AdS_3$ background and find that at a specific value of a certain combination of the two mass parameters (chiral line), on

  21. Eduardo Guendelman, Alexander Kaganovich, Emil Nissimov, Svetlana Pacheva

    Lightlike p-branes (LL-branes) with dynamical (variable) tension allow simple and elegant Polyakov-type and dual to it Nambu-Goto-like world-volume action formulations. Here we first briefly describe the dynamics of LL-branes as test objects in various physically interesting gravitational backgrounds of black hole type, including rotating ones. Next we show

  22. Catarina Bastos, Orfeu Bertolami, Nuno Dias, Joao Nuno Prata

    We present a phase-space noncommutative version of quantum mechanics and apply this extension to Quantum Cosmology. We motivate this type of noncommutative algebra through the gravitational quantum well (GQW) where the noncommutativity between momenta is shown to be relevant. We also discuss some qualitative features of the GQW such as the Berry phase. In th

  23. A. Ashoorioon, T. Konstandin

    We discuss the question if the upcoming generation of collider and low-energy experiments can successfully probe the nature of the electroweak phase transition. In particular, we are interested in phase transitions strong enough for electroweak baryogenesis or even for a production of gravitational radiation observable by the Big Bang Observer. As an explici

  24. Norio Konno

    We consider discrete-time nearest-neighbor quantum walks on random environments in one dimension. Using the method based on a path counting, we present both quenched and annealed weak limit theorems for the quantum walk.

  25. S. Zhang, Y. H. Zhu, G. L. Ma, Y. G. Ma

    The system size dependence of dihadron azimuthal correlations in ultra-relativistic heavy ion collision is simulated by a multi-phase transport model. The structure of correlation functions and yields of associated particles show clear participant path-length dependences in collision systems with a partonic phase. The splitting parameter ($D$) and Root Mean

  26. Fernando G. S. L. Brandao, Martin B. Plenio

    We present a generalization of quantum Stein's Lemma to the situation in which the alternative hypothesis is formed by a family of states, which can moreover be non-i.i.d.. We consider sets of states which satisfy a few natural properties, the most important being the closedness under permutations of the copies. We then determine the error rate function

  27. Didar Dobur

    We report on potential for measurement of W and Z boson production, as well as the production in association with jets. Of particular interest are jet multiplicity and $P_{\rm T}$ distributions. The 10 to $100 {\rm pb}^{-1}$ datasets expected in the startup year of operation of LHC are likely to already provide information beyond the reach of the Tevatron co

  28. Fyodor Tkachov

    The idea that an internal quantum number for quarks, eventually called color, can explain the magnetic moments of baryons within the framework of standard quantum theory, was explicitly stated in a 7th January, 1965 JINR publication by Boris Struminsky (JINR P-1939). A complete translation into English of Struminsky's letter is presented along with page

  29. Vidian Rousse

    In this article, a class of Fourier Integral Operators which converge to the unitary group of the Schrödinger equation in semiclassical limit $ε\to 0$ is constructed. The convergence is in the uniform operator norm and allows for a error bound $C_Nε^{N+1}$ for any integer $N$ and extends to Ehrenfest timescaleswith bound $C_Nε^{N+1-ρ}$ where $ρ$ can be made

  30. J. C. Hafele

    In 2008 a group of NASA scientists reported an anomalous change in the speed of six spacecraft flybys of the Earth. The reported speed change for the NEAR spacecraft flyby is 13.46+-0.01 mm/s. It is known that general relativity theory reduces to classical time-retarded electromagnetic field theory in the linearized approximation. This report shows that time

  31. Gechun Liang, Terry Lyons, Zhongmin Qian

    We demonstrate that backward stochastic differential equations (BSDE) may be reformulated as ordinary functional differential equations on certain path spaces. In this framework, neither Itô's integrals nor martingale representation formulate are needed. This approach provides new tools for the study of BSDE, and is particularly useful for the study of B

  32. Yu. L. Bolotin, V. A. Cherkaskiy, G. I. Ivashkevych, O. A. Lemets

    To our best knowledge, there are no problem books on cosmology yet, that would include its spectacular recent achievements. We believe there is a strong need for such now, when cosmology is swiftly becoming a strict and vast science, and the book would be extremely useful for the youth pouring in this area of research. Indeed, the only way to rise over the p

  33. Stephanie Trine, Susanne Westhoff, Soren Wiesenfeldt

    We consider corrections to the unification of down-quark and charged-lepton Yukawa couplings in supersymmetric GUTs, which links the large nu_tau-nu_mu mixing angle to b -> s transitions. These corrections generically occur in simple grand-unified models with small Higgs representations and affect s -> d and b -> d transitions via the mixing of the correspon

  34. S. Reibe, Ph. von Doetinchem, B. Madea

    Homicide investigations often depend on the determination of a minimum post-mortem interval (PMI$_{min}$) by forensic entomologists. The age of the most developed insect larvae (mostly blow fly larvae) gives reasonably reliable information about the minimum time a person has been dead. Methods such as isomegalen diagrams or ADH calculations can have problems

  35. B. R. Mushailov, V. S. Teplitskaya

    Some principles in the distribution of Centaurs and the "Scattered Disk" objects, as well as the Kuiper belt objects for its semi-major axes, eccentricities and inclinations of the orbits have been investigated. It has been established, that more than a half from them move on the resonant orbits and that is what has been predicted earlier. The diverg

  36. Leonardo Brizi, Marta Gomez-Reino, Claudio A. Scrucca

    We reconsider the general question of how to characterize most efficiently the low-energy effective theory obtained by integrating out heavy modes in globally and locally supersymmetric theories. We consider theories with chiral and vector multiplets and identify the conditions under which an approximately supersymmetric low-energy effective theory can exist

  37. Petter Brändén

    Murota et al. have recently developed a theory of discrete convex analysis which concerns M-convex functions on jump systems. We introduce here a family of M-concave functions arising naturally from polynomials (over a field of generalized Puiseux series) with prescribed non-vanishing properties. This family contains several of the most studied M-concave fun

  38. D. Nardi, F. Banfi, C. Giannetti, B. Revaz

    We present a theoretical framework allowing to properly address the nature of surface-like eigenmodes in a hypersonic surface phononic crystal, a composite structure made of periodic metal stripes of nanometer size and periodicity of 1 micron, deposited over a semi-infinite silicon substrate. In surface-based phononic crystals there is no distinction between

  39. Etienne Birmele

    Studying the topology of so-called {\em real networks}, that is networks obtained from sociological or biological data for instance, has become a major field of interest in the last decade. One way to deal with it is to consider that networks are built from small functional units called {\em motifs}, which can be found by looking for small subgraphs whose nu

  40. Luigi Ambrosio, Gianluca Crippa, Alessio Figalli, Laura V. Spinolo

    We obtain various new well-posedness results for continuity and transport equations, among them an existence and uniqueness theorem (in the class of strongly continuous solutions) in the case of nearly incompressible vector fields, possibly having a blow-up of the BV norm at the initial time. We apply these results (valid in any space dimension) to the k x k

  41. J. Christensen-Dalsgaard

    The Sun is unique amongst stars in having a precisely determined age which does not depend on the modelling of stellar evolution. Furthermore, other global properties of the Sun are known to much higher accuracy than for any other star. Also, helioseismology has provided detailed determination of the solar internal structure and rotation. As a result, the Su

  42. Nianbei Li, Fei Zhan, Peter Hanggi, Baowen Li

    We investigate directed thermal heat flux across 1D homogenous nonlinear lattices when no net thermal bias is present on average. A nonlinear lattice of Fermi-Pasta-Ulam-type or Lennard-Jones-type system is connected at both ends to thermal baths which are held at the same temperature on temporal average. We study two different modulations of the heat bath t

  43. Ivan Brihuega, Antonio M. Garcia-Garcia, Pedro Ribeiro, Miguel M. Ugeda

    An important question in the physics of superconducting nanostructures is the role of thermal fluctuations on superconductivity in the zero-dimensional limit. Here, we probe the evolution of superconductivity as a function of temperature and particle size in single, isolated Pb nanoparticles. Accurate determination of the size and shape of each nanoparticle

  44. Shlomi Dolev, Yuval Elovici, Rami Puzis, Polina Zilberman

    In many applications we are required to increase the deployment of a distributed monitoring system on an evolving network. In this paper we present a new method for finding candidate locations for additional deployment in the network. This method is based on the Group Betweenness Centrality (GBC) measure that is used to estimate the influence of a group of n

  45. The BABAR Collaboration, B. Aubert

    We search for the neutrinoless, lepton-flavor-violating tau decays tau -> l V^0, where l is an electron or muon and V^0 is a vector meson reconstructed as phi -> K^+K^-, rho -> pi^+pi^-, K^* -> K^+pi^-, or K^*bar -> K^-pi^+. The analysis has been performed using 451 fb^{-1} of data collected at an e^+e^- center-of-mass energy near 10.58 GeV with the BaBar de

  46. Yusuke Arike

    In this paper we will find a matrix realizations of the quantum group g_{p, q}. For this purpose, we construct all primitive idempotents and a basis of g_{p, q}. We determine the action of elements of the basis on the indecomposable projective modules, which give rise to a matrix realization of g_{p, q}. By using this result, we obtain a basis of the space o

  47. Mary Rees

    We describe a fundamental domain for the punctured Riemann surface $V_{3,m}$ which parametrises (up to Möbius conjugacy) the set of quadratic rational maps with numbered critical points, such that the first critical point has period three, and such that the second critical point is not mapped in $m$ iterates or less to the periodic orbit of the first. This g

  48. Judit Abardia, Eduardo Gallego, Gil Solanes

    We compute the measure with multiplicity of the set of complex planes intersecting a compact domain in a complex space form. The result is given in terms of the so-called hermitian intrinsic volumes. Moreover, we obtain two different versions for the Gauss-Bonnet-Chern formula in complex space forms. One of them gives the Gauss curvature integral in terms of

  49. Xiang-Song Chen, Wei-Min Sun, Xiao-Fu Lü, Fan Wang

    We examine the conventional picture that gluons carry about half of the nucleon momentum in the asymptotic limit. We reveal that this large fraction is due to an unsuitable definition of the gluon momentum in an interacting theory. If defined in a gauge-invariant and consistent way, the asymptotic gluon momentum fraction is computed to be only about one fift

  50. L. B. Leinson

    The linear response of a nonrelativistic superfluid baryon system on an external weak field is investigated while taking into account of the Fermi-liquid interactions. We generalize the theory developed by Leggett for a superfluid Fermi-liquid at finite temperature to the case of timelike momentum transfer typical of the problem of neutrino emission from neu

  51. C. S. Kim, Ru-Min Wang

    We present a complete study of R-parity violating supersymmetric effects in thirteen exclusive and inclusive semi-leptonic $b \to (s,d) ν\barν$ decays, including $B^+_u\to K^{(*)+}ν\barν$, $B^0_d\to K^{(*)0}ν\barν$, $B^0_s\to ϕν\barν$, $B^0_d\to π^0(ρ^0)ν\barν$, $B^+_u\to π^+(ρ^+)ν\barν$, $B^0_s\to K^{(*)0}ν\barν$ and $B \to X_{s,d} ν\barν$ decay modes, and

  52. J. H. Asad, R. S. Hijjawi, A. J. Sakaji, J. M. Khalifeh

    The capacitance between the origin and any other lattice site in an infinite square lattice of identical capacitors is studied. The method is generalized to infinite Simple Cubic (SC) lattice. We make use of the superposition principle and the symmetry of the infinite grid

  53. Masahito Hayashi

    We derive a new upper bound for Eve's information in secret key generation from a common random number without communication. This bound improves on Bennett et al(1995)'s bound based on the Rényi entropy of order 2 because the bound obtained here uses the Rényi entropy of order $1+s$ for $s \in [0,1]$. This bound is applied to a wire-tap channel. The

  54. Taeseung Choi

    We show the additional spin dependent classical force due to the rotation of an electron spin's rest frame is essential to derive a spin-Faraday law by using an analogy with the usual Faraday law. The contribution of the additional spin dependent force to the spin-Faraday law is the same as that of the spin geometric phase. With this observations, Farada

  55. Yuval Grossman, Yosef Nir, Gilad Perez

    If new CP violating physics contributes to neutral meson mixing, but its contribution to CP violation in decay amplitudes is negligible, then there is a model independent relation between four (generally independent) observables related to the mixing: The mass splitting (x), the width splitting (y), the CP violation in mixing (1-|q/p|), and the CP violation

  56. Hokuto Uehara

    We study the Fourier--Mukai numbers of rational elliptic surfaces. As its application, we give an example of a pair of minimal 3-folds with Kodaira dimensions 1, $h^1(\mc O)=h^2(\mc O)=0$ such that they are mutually derived equivalent, deformation equivalent, but not birationally equivalent. It also supplies a counterexample of the birational Torelli problem

  57. Hem C. Kandpal, Ingo Opahle, Yu-Zhong Zhang, Harald O. Jeschke

    Intense experimental and theoretical studies have demonstrated that the anisotropic triangular lattice as realized in the kappa-(BEDT-TTF)2X family of organic charge transfer (CT) salts yields a complex phase diagram with magnetic, superconducting, Mott insulating and even spin liquid phases. With extensive density functional theory (DFT) calculations we ref

  58. Michele Di Cristo, Sergio Vessella

    We deal with the problem of determining a time varying inclusion within a thermal conductor. In particular we study the continuous dependance of the inclusion from the Dirichlet-to-Neumann map. Under a priori regularity assumptions on the unknown defect we establish logarithmic stability estimates.

  59. Gennady Agre, Petar Kormushev, Ivan Dilov

    The current INFRAWEBS European research project aims at developing ICT framework enabling software and service providers to generate and establish open and extensible development platforms for Web Service applications. One of the concrete project objectives is developing a full-life-cycle software toolset for creating and maintaining Semantic Web Services (S

  60. Sylvia H. Sutanto, Paulus C. Tjiang

    The Gaussian formula and spherical aberrations of the static and relativistic curved mirrors are analyzed using the optical path length (OPL) and Fermat's principle. The geometrical figures generated by the rotation of conic sections about their symmetry axes are considered for the shapes of the mirrors. By comparing the results in static and relativisti

  61. Vsevolod Shevchishin

    We introduce the secondary Stiefel-Whitney class $\tilde w_2$ of homotopically trivial diffeomorphisms and show that a homotopically trivial symplectomorphism of a ruled 4-manifold is isotopic to identity if and only if the class $\tilde w_2$ vanishes. Using this, we give a detailed description of the combinatorial structure of the diffeotopy group of ruled

  62. Takuya Okabe

    We investigate theoretically the Seebeck effect in materials close to a ferromagnetic quantum critical point to explain anomalous behaviour at low temperatures. It is found that the main effect of spin fluctuations is to enhance the coefficient of the leading $T$-linear term, and a quantum critical behaviour characterized by a spin-fluctuation temperature ap

  63. Quentin G. Bailey

    Modifications to the classic time-delay effect and Doppler shift in General Relativity (GR) are studied in the context of the Lorentz-violating Standard-Model Extension (SME). We derive the leading Lorentz-violating corrections to the time-delay and Doppler shift signals, for a light ray passing near a massive body. It is demonstrated that anisotropic coeffi

  64. Fang Wu, Bernardo A. Huberman

    A hallmark of the attention economy is the competition for the attention of others. Thus people persistently upload content to social media sites, hoping for the highly unlikely outcome of topping the charts and reaching a wide audience. And yet, an analysis of the production histories and success dynamics of 10 million videos from \texttt{YouTube} revealed

  65. M. Nemouchi, M. R. Godefroid

    The relativistic corrections to the magnetic dipole moment operator in the Pauli approximation were derived originally by Drake (Phys. Rev. A 3(1971)908). In the present paper, we derive their irreducible tensor-operator form to be used in atomic structure codes adopting the Fano-Racah-Wigner algebra for calculating its matrix elements.

  66. David Bachman

    Let M_1 and M_2 be compact, orientable 3-manifolds, and M the manifold obtained by gluing some component F of \bdy M_1 to some component of \bdy M_2 by a homeomorphism ϕ. We show that when ϕis "sufficiently complicated" then (1) the amalgamation of low genus, unstabilized, boundary-unstabilized Heegaard splittings of M_i is an unstabilized splitting

  67. J. C. López Vieyra, M. A. G. García, A. V. Turbiner

    It is shown that the $E_7$ trigonometric Olshanetsky-Perelomov Hamiltonian, when written in terms of the Fundamental Trigonometric Invariants (FTI), is in algebraic form, i.e., has polynomial coefficients, and preserves the infinite flag of polynomial spaces with the characteristic vector $\vec α= (1,2,2,2,3,3,4)$. Its flag coincides with one of the minimal

  68. Robert D. Schroll, Christophe Josserand, Stéphane Zaleski, Wendy W. Zhang

    We simulate the impact of a viscous liquid drop onto a smooth dry solid surface. As in experiments, when ambient air effects are negligible, impact flattens the falling drop without producing a splash. The no-slip boundary condition at the wall produces a boundary layer inside the liquid. Later, the flattening surface of the drop traces out the boundary laye

  69. A. C. Seridonio, F. M. Souza, J. Del Nero, I. A. Shelykh

    We study spin-dependent conductance in a system composed of a ferromagnetic (FM) Scanning Tunneling Microscope (STM) tip coupled to a metallic host surface with an adatom. The Kondo resonance is taken into account via the Doniach-Sunjic spectral function. For short lateral tip-adatom distances and due to the interplay between Kondo physics, quantum interferi

  70. Pierre Dolbeault, Giuseppe Tomassini, Dmitri Zaitsev

    We address the problem of existence and uniqueness of a Levi-flat hypersurface $M$ in $C^n$ with prescribed compact boundary $S$ for $n\ge3$. The situation for $n\ge3$ differs sharply from the well studied case $n=2$. We first establish necessary conditions on $S$ at both complex and CR points, needed for the existence of $M$. All CR points have to be nonmin

  71. Giovanni Filatrella, Boris A. Malomed, Luca Salasnich

    We study suppression of the collapse and stabilization of matter-wave solitons by means of time-periodic modulation of the effective nonlinearity, using the nonpolynomial Schroedinger equation (NPSE) for BEC trapped in a tight cigar-shaped potential. By means of systematic simulations, a stability region is identified in the plane of the modulation amplitude

  72. H. Rampadarath, M. A. Garrett, A. Polatidis

    Aims. We have analysed VLBA 92cm archive data of 44 extragalactic sources in order to identify early targets and potential calibrator sources for the LOFAR radio telescope and the RadioAstron space VLBI mission. Some of these sources will also be suitable as in-beam calibrators, permitting deep, wide-field studies of other faint sources in the same field of

  73. Mukunda P. Das, Frederick Green

    Having driven a large part of the decade's progress in physics, nanoelectronics is now passing from today's realm of the extraordinary to tomorrow's commonplace. This carries the problem of turning proofs of concept into practical artefacts. Better and more sharply focussed predictive modelling will be the ultimate guide to optimising mesoscopic

  74. Olivera Miskovic, Jorge Zanelli

    In (2+1)-dimensional gravity with negative cosmological constant, the states in the negative energy range, between AdS (M=-1) and the so-called BTZ black hole ($M\geq 0$), correspond to topological defects with angular deficit $0<\alpha <2\pi $. These defects are produced by (static or spinning) 0-branes which, in the extreme case $M\ell =-|J|$, admit global

  75. J. M. Landsberg, Jason Morton, Serguei Norine

    The theory of holographic algorithms, which are polynomial time algorithms for certain combinatorial counting problems, yields insight into the hierarchy of complexity classes. In particular, the theory produces algebraic tests for a problem to be in the class P. In this article we streamline the implementation of holographic algorithms by eliminating one of

  76. Petr Navratil, Sofia Quaglioni, Ionel Stetcu, Bruce R. Barrett

    We present an overview of recent results and developments of the no-core shell model (NCSM), an ab initio approach to the nuclear many-body problem for light nuclei. In this approach, we start from realistic two-nucleon or two- plus three-nucleon interactions. Many-body calculations are performed using a finite harmonic-oscillator (HO) basis. To facilitate c

  77. J. Chluba, R. A. Sunyaev

    We give a formulation of the radiative transfer equation for Lyman alpha photons which allows us to include the two-photon corrections for the 3s-1s and 3d-1s decay channels during cosmological hydrogen recombination. We use this equation to compute the corrections to the Sobolev escape probability for Lyman alpha photons during hydrogen recombination, which

  78. Filippo Callegaro, Davide Moroni, Mario Salvetti

    We consider two natural embeddings between Artin groups: the group G_{tilde{A}_{n-1}} of type tilde{A}_{n-1} embeds into the group G_{B_n} of type B_n; G_{B_n} in turn embeds into the classical braid group Br_{n+1}:=G_{A_n} of type A_n. The cohomologies of these groups are related, by standard results, in a precise way. By using techniques developed in previ

  79. Ramanath Cowsik, Kasey Wagoner, Emanuele Berti, Amit Sircar

    In the Fornax dwarf spheroidal galaxy the globular clusters are distributed widely, without any significant central concentration. Oh et al. pointed out that such a distribution is paradoxical: dynamical friction effects estimated using single-component King models would have forced the globular clusters to spiral down to the center of the galaxy well within

  80. Kenneth L. Pryor

    A GOES-West (GOES-11) imager microburst algorithm that employs brightness temperature differences between band 3, band 4, and split window band 5 has been developed to supplement the sounder-derived microburst products. Band 3 is intended to indicate mid to upper-level moisture content and advection while band 5 indicates low-level moisture content. Large BT

  81. Le Anh Vinh

    In this paper we will give a unified proof of several results on the sovability of systems of certain equations over finite fields, which were recently obtained by Fourier analytic methods. Roughly speaking, we show that almost all systems of norm, bilinear or quadratic equations over finite fields are solvable in any large subset of vector spaces over finit

  82. O. Burtseva, S. C. Tripathy, F. Hill, S. Kholikov

    We investigate mode amplitudes in the active and quiet Sun in both maximum and minimum phases of the solar activity cycle. We confirm previous studies showing that p-mode amplitudes at solar minimum are higher than at solar maximum. We mask active regions of a certain magnetic field strength and compare the masked and unmasked acoustic power. After applying

  83. STAR Collaboration, B. I. Abelev

    The STAR collaboration at RHIC presents measurements of \Jpsi$\to{e^+e^-}$ at mid-rapidity and high transverse momentum ($p_T>5$ GeV/$c$) in \pp and central \cucu collisions at \sNN = 200 GeV. The inclusive \Jpsi production cross section for \cucu collisions is found to be consistent at high $p_T$ with the binary collision-scaled cross section for \pp collis

  84. Thierry Mora, Howard Yu, Yoshiyuki Sowa, Ned S. Wingreen

    The bacterial flagellar motor is a highly efficient rotary machine used by many bacteria to propel themselves. It has recently been shown that at low speeds its rotation proceeds in steps [Sowa et al. (2005) Nature 437, 916--919]. Here we propose a simple physical model that accounts for this stepping behavior as a random walk in a tilted corrugated potentia

  85. Vincent Rialle, Catherine Ollivet, Carole Guigui, Christian Hervé

    Objectives - The authors&#39; aim was to investigate the representations, wishes, and fears of family caregivers (FCs) regarding 14 innovative technologies (IT) for care aiding and burden alleviation, given the severe physical and psychological stress induced by dementia care, and the very slow uptake of these technologies in our society. Methods - A cluster

  86. F. Paerels, M. Mendez, M. Agueros, M. Baring

    The cores of neutron stars harbor the highest matter densities known to occur in nature, up to several times the densities in atomic nuclei. Similarly, magnetic field strengths can exceed the strongest fields generated in terrestrial laboratories by ten orders of magnitude. Hyperon-dominated matter, deconfined quark matter, superfluidity, even superconductiv

  87. Marcin Daszkiewicz

    We construct five new quantum Newton-Hooke Hopf algebras with the use of Abelian twist procedure. Further we demonstrate that the corresponding deformed space-times with quantum space and classical time are periodic or expanding in time.

  88. Holger Bech Nielsen, Ismail Zahed

    The Cheshire cat principle states that hadronic observables at low energy do not distinguish between hard (quark) or soft (meson) constituents. As a result, the delineation between hard/soft (bag radius) is like the Cheshire cat smile in Alice in wonderland. This principle reemerges from current holographic descriptions of chiral baryons whereby the smile ap

  89. Francoise Demengel

    In this paper we prove some existence and regularity results concerning parabolic equations dtu = F(D u, D2 u) + f(x,u) with some boundary conditions, on Omega times ]0,T[, where Omega is some bounded domain which possesses the cone property and $F$ is singular or degenerate, with some uniform ellipticity conditions.

  90. Christian Frønsdal

    In this second article of a series we propose to base criteria of stability on the hamiltonian functional that is provided by the variational principle, to replace the reliance that has often been placed on {\it ad hoc} definitions of the &#34;energy&#34;. We introduce a new virial principle that is formulated entirely within the Eulerian description of hydr

  91. Colin Reid

    The generalised Fitting subgroup of a finite group is the group generated by all subnormal subgroups that are either nilpotent or quasisimple. The importance of this subgroup in finite group theory stems from the fact that it always contains its own centraliser, so that any finite group is an abelian extension of a group of automorphisms of its generalised F

  92. J. Socorro, M. Sabido, L. Arturo Ureña-López

    We study the generalization of the Sáez-Ballester theory applied to a flat FRW cosmological model. Classical exact solutions up to quadratures are easily obtained using the Hamilton-Jacobi approach. Contrary to claims in the specialized literature, it is shown that the Sáez-Ballester theory cannot provide a realistic solution to the dark matter problem of Co

  93. A. Calle Cordon, E. Ruiz Arriola

    The Serber force has relative orbital parity symmetry and requires vanishing NN interactions in partial waves with odd angular momentum. We illustrate how this property is well fulfilled for spin triplet states with odd angular momentum and violated for odd singlet states for realistic potentials but fails for chiral potentials. We analyze how Serber symmetr

  94. Irving O. Morales, J. C. López Vieyra, J. G. Hirsch, A. Frank

    The Garvey-Kelson relations are used in an iterative process to predict nuclear masses in the neighborhood of nuclei with measured masses. Average errors in the predicted masses for the first three iteration shells are smaller than those obtained with the best nuclear mass models. Their quality is comparable with the Audi-Wapstra extrapolations, offering a s

  95. Marco Budinich

    After a brief discussion of the computational complexity of Clifford algebras, we present a new basis for even Clifford algebra Cl(2m) that simplifies greatly the actual calculations and, without resorting to the conventional matrix isomorphism formulation, obtains the same complexity. In the last part we apply these results to the Clifford algebra formulati

  96. Sang-Bum Lee, Juhee Yang, Songky Moon, Soo-Young Lee

    We experimentally studied evolution of quasi-eigenmodes as classical dynamics undergoing a transition from being regular to chaotic in open quantum billiards. In a deformation-variable microcavity we traced all high-Q cavity modes in a wide range of frequency as the cavity deformation increased. By employing an internal parameter we were able to obtain a mod

  97. A. Eggenberger, S. Udry

    Over 300 extrasolar planets have been found since 1992, showing that planetary systems are common and exhibit an outstanding variety of characteristics. As the number of detections grows and as models of planet formation progress to account for the existence of these new worlds, statistical studies and confrontations of observation with theory allow to progr

  98. Jeffrey Winicour

    The principle part of Einstein equations in the harmonic gauge consists of a constrained system of 10 curved space wave equations for the components of the space-time metric. A well-posed initial boundary value problem based upon a new formulation of constraint-preserving boundary conditions of the Sommerfeld type has recently been established for such syste

  99. A. A. Andrianov, V. A. Andrianov, D. Espriu

    We investigate the possibility of parity being spontaneously violated in QCD at finite baryon density and temperature. The analysis is done for an idealized homogeneous and infinite nuclear matter where the influence of density can be examined with the help of constant chemical potential. QCD is approximated by a generalized sigma-model with two isomultiplet

  100. M. H. L. S. Wang

    We present the latest measurements of the top quark mass from the Tevatron. The different top decay channels and measurement techniques used for these results are also described. The world average of the top quark mass based on some of these new results combined with previous results is mtop=172.6+-1.4 GeV.