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February 2009 arXiv papers — page 37

Showing 3,6013,700 of 4,929 papers

  1. L. N. Lipatov

    We argue, that the multi-particle scattering amplitudes in N=4 SUSY at large $N_c$ and in the multi-Regge kinematics for some physical regions have the high energy behavior appearing from the contribution of the Mandelstam cuts in the corresponding $t$-channel partial waves. The Mandelstam cuts correspond to gluon composite states in the adjoint representati

  2. C. Butucea, F. Comte

    We consider the model $Z_i=X_i+\varepsilon_i$, for i.i.d. $X_i$'s and $\varepsilon_i$'s and independent sequences $(X_i)_{i\in{\mathbb{N}}}$ and $(\varepsilon_i)_{i\in{\mathbb{N}}}$. The density $f_{\varepsilon}$ of $\varepsilon_1$ is assumed to be known, whereas the one of $X_1$, denoted by $g$, is unknown. Our aim is to estimate linear functionals

  3. Pietro Di Lena, Luciano Margara

    Cellular Automata (CA) are discrete dynamical systems and an abstract model of parallel computation. The limit set of a cellular automaton is its maximal topological attractor. A well know result, due to Kari, says that all nontrivial properties of limit sets are undecidable. In this paper we consider properties of limit set dynamics, i.e. properties of the

  4. Koji S. Kawabata, Masaomi Tanaka, Keiichi Maeda, Takashi Hattori

    We performed optical spectroscopy and photometry of SN 2006gy at late time, ~400 days after the explosion, with the Subaru/FOCAS in a good seeing condition. We found that the SN faded by ~3 mag from ~200 to ~400 days after the explosion (i.e., by ~5 mag from peak to ~400 days) in R band. The overall light curve is marginally consistent with the 56Ni heating

  5. Ludwig Baringhaus, Rudolf Grübel

    Given two independent samples of non-negative random variables with unknown distribution functions $F$ and $G$, respectively, we introduce and discuss two tests for the hypothesis that $F$ is less than or equal to $G$ in increasing convex order. The test statistics are based on the empirical stop-loss transform, critical values are obtained by a bootstrap pr

  6. Yota Takamura, Ryosho Nakane, Satoshi Sugahara

    The authors developed a new analysis approach for evaluation of atomic ordering in full-Heusler alloys, which is extension of the commonly used Webster model. Our model can give accurate physical formalism for the degree of atomic ordering in the L21 structure, including correction with respect to the fully disordered A2 structure, i.e., the model can direct

  7. C. Deninger, A. Werner

    We extend our previous theory of etale parallel transport to a larger class of slope zero vector bundles on p-adic curves. The new class is stable under pullback by ramified coverings. We also construct p-adic representations of a central extension of the fundamental group for certain bundles of non-zero slope.

  8. Nikolai Nadirashvili, Serge Vladuts

    We prove the existence of non-smooth solutions to Special Lagrangian Equations in the non-convex case.

  9. Rostislav Devyatov

    In the article, a series of neigbourly polyhedra is constructed. They have $N=2d+4$ vertices and are embedded in $\mathbb R^{2d}$. Their (affine) Gale diagrams in $\mathbb R^2$ have $d+3$ black points that form a convex polygon. These Gale diagams can be enumerated using 3-trees (trees with some additional structure). Given $d$ and $m$, each of the construct

  10. S. Mazouffre, D. Gawron, N. Sadeghi

    The temporal characteristics of the Xe$^+$ ion axial Velocity Distribution Function (VDF) were recorded in the course of low-frequency discharge current oscillations ($\sim$~14 kHz) of the 5 kW-class PPS$\circledR$X000 Hall thruster. The evolution in time of the ion axial velocity component is monitored by means of a laser induced fluorescence diagnostic too

  11. F. Kagawa, Y. Kurosaki, K. Miyagawa, K. Kanoda

    We investigated the magnetism under a magnetic field in the quasi-two-dimensional organic Mott insulator $κ$-(BEDT-TTF)$_{2}$Cu[N(CN)$_{2}$]Cl through magnetization and $^{13}$C-NMR measurements. We found that in the nominally paramagnetic phase (i.e., above Néel temperature) the field-induced local moments have a staggered component perpendicular to the app

  12. C. Javaux, I. G. Hughes, G. Lochead, J. Millen

    We have performed polarization spectroscopy and sub-Doppler DAVLL on the (5s5s) 1^S_0 -> (5s5p) 1^P_1 transition of atomic strontium. Both techniques generated a dispersion-type lineshape suitable for laser stabilization, without the need for frequency modulation. In both cases the signal is generated primarily by saturation effects, rather than optical pump

  13. Marcin Zwierz, Pieter Kok

    We demonstrate theoretically a scheme for cluster state generation, based on atomic ensembles and the dipole blockade mechanism. In the protocol, atomic ensembles serve as single qubit systems. Therefore, we review single-qubit operations on qubit defined as collective states of atomic ensemble. Our entangling protocol requires nearly identical single-photon

  14. Holger Dette, Andrey Pepelyshev, Weng Kee Wong

    We construct optimal designs for estimating fetal malformation rate, prenatal death rate and an overall toxicity index in a toxicology study under a broad range of model assumptions. We use Weibull distributions to model these rates and assume that the number of implants depend on the dose level. We study properties of the optimal designs when the intra-litt

  15. V. A. Galaktionov, E. Mitidieri, S. I. Pohozaev

    Three classes of higher-order nonlinear parabolic hyperbolic, and nonlinear dispersion equations are shown to admit exact blow-up or compacton solutions, which are induced by elliptic equations with non-Lipschitz nonlinearities. Variational techniques give countable families of various compactly supported solutions with oscllatory behaviour cloase to the int

  16. S. Fugmann, I. M. Sokolov

    We consider the rupture dynamics of a homopolymer chain pulled at one end at a constant loading rate. Our model of the breakable polymer is related to the Rouse chain, with the only difference that the interaction between the monomers is described by the Morse potential instead of the harmonic one, and thus allows for mechanical failure. We show that in the

  17. D. Oellers, L. Barion, S. Barsov, U. Bechstedt

    We discuss polarizing a proton beam in a storage ring, either by selective removal or by spin flip of the stored ions. Prompted by recent, conflicting calculations, we have carried out a measurement of the spin flip cross section in low-energy electron-proton scattering. The experiment uses the cooling electron beam at COSY as an electron target. The measure

  18. Giampaolo Piotto

    An increasing number of photometric observations of multiple stellar populations in Galactic globular clusters is seriously challenging the paradigm of GCs hosting single, simple stellar populations. These multiple populations manifest themselves in a split of different evolutionary sequences as observed in the cluster color-magnitude diagrams. Multiple stel

  19. Natasha Hurley-Walker, A. M. M. Scaife, D. A. Green, Matthew L. Davies

    We present observations between 14.2 and 17.9 GHz of 12 reported supernova remnants (SNRs) made with the Arcminute Microkelvin Imager Small Array (AMI SA). In conjunction with data from the literature at lower radio frequencies, we determine spectra of these objects. For well-studied SNRs (Cas A, Tycho's SNR, 3C58 and the Crab Nebula), the results are in

  20. Sarah E. Rogers, Kaihsu Tai, Oliver Beckstein, Mark S. P. Sansom

    To what extent must a hydrophobic gate expand for the channel to count as open? We address this question using the nicotinic acetylcholine receptor (nAChR) as the exemplar. The nAChR is an integral membrane protein which forms a cation selective channel gated by neurotransmitter binding to its extracellular domain. A hydrophobic gating model has been propose

  21. A. Kozela, G. Ban, A. Białek, K. Bodek

    Both components of the transverse polarization of electrons emitted in the beta-decay of polarized, free neutrons have been measured. The T-odd, P-odd correlation coefficient quantifying the component perpendicular to the decay plane defined by neutron polarization and electron momentum, was found to be R=0.008 +/- 0.015 +/-0.005. This value is consistent wi

  22. Detlef Klimm, Ivanildo A. dos Santos, Izilda M. Ranieri, Sonia L. Baldochi

    The scheelite type laser crystals LiREF4 melt congruently only for RE being one of the elements Er, Tm, Yb, Lu, or possibly Y, respectively. For RE = Eu, Gd, Tb, Dy, or Ho the corresponding scheelites undergo a peritectic melting under the formation of the corresponding rare earth fluoride. The melting behavior of LiREF4 mixed crystals with two or more RE is

  23. F. Kagawa, M. Mochizuki, Y. Onose, H. Murakawa

    We report the dielectric dispersion of the giant magnetocapacitance (GMC) in multiferroic DyMnO$_{3}$ over a wide frequency range. The GMC is found to be attributable not to the softened electromagnon but to the electric-field-driven motion of multiferroic domain wall (DW). In contrast to conventional ferroelectric DWs, the present multiferroic DW motion hol

  24. Dirk Blomker, Marco Romito

    The paper contains several regularity results and blow-up criterions for a surface growth model, which seems to have similar properties to the 3D Navier-Stokes, although it is a scalar equation. As a starting point we focus on energy methods and Lyapunov-functionals.

  25. G. A. Sokol, E. M. Leikin

    Experimental studies of possible modifications of isoscalar-meson properties in nuclear medium are proposed.

  26. Marco Romito

    We prove existence of weak martingale solutions satisfying an almost sure version of the energy inequality and which constitute a (almost sure) Markov process.

  27. Yu. A. Simonov, V. I. Shevchenko

    Confinement in QCD is caused by vacuum fluctuations of gluon fields. There are two numerically different scales, characterizing nonperturbative QCD vacuum dynamics: a "small" scale, corresponding to gluon condensate, critical temperature etc, which is about 0.2-0.3 GeV, and a "large" one, given by inverse confining string width, glueball and

  28. Christian Berg, Antonio J. Durán

    We prove that certain sequences of finite continued fractions associated with a 2-periodic continued fraction with period a,b>0 are moment sequences of discrete signed measures supported in the interval [-1,1], and we give necessary and sufficient conditions in order that these measures are positive. For a=b=1 this proves that the sequence of ratios F_{n+1}/

  29. Henghsiu Tsai

    In this paper, we consider a continuous-time autoregressive fractionally integrated moving average (CARFIMA) model, which is defined as the stationary solution of a stochastic differential equation driven by a standard fractional Brownian motion. Like the discrete-time ARFIMA model, the CARFIMA model is useful for studying time series with short memory, long

  30. Marco Romito

    Under suitable assumptions of regularity and non-degeneracy on the covariance of the driving additive noise, any Markov solution to the stochastic Navier-Stokes equations has an associated generator of the diffusion and is the unique solution to the corresponding martingale problem. Some elementary examples are discussed to interpret these results.

  31. Erik D. Demaine, Mohammadtaghi Hajiaghayi, Hamid Mahini, Morteza Zadimoghaddam

    In general, the games are played on a host graph, where each node is a selfish independent agent (player) and each edge has a fixed link creation cost α. Together the agents create a network (a subgraph of the host graph) while selfishly minimizing the link creation costs plus the sum of the distances to all other players (usage cost). In this paper, we purs

  32. P. M. Alsing, G. J. Stephenson

    We investigate the Wigner rotation for photons, which governs the change in the polarization of the photon as it propagates through an arbitrary gravitational field. We give explicit examples in Schwarzschild spacetime, and compare with the corresponding flat spacetime results, which by the equivalence principle, holds locally at each spacetime point. We dis

  33. Zoran Škoda

    Earlier, Lunts and Rosenberg studied a notion of compatibility of endofunctors with localization functors, with an application to the study of differential operators on noncommutative rings and schemes. Another compatibility -- of Ore localizations of an algebra with a comodule algebra structure over a given bialgebra -- introduced in my earlier work -- is h

  34. Xian-Shi Lin, Xu-Guang Huang

    In this paper, we theoretically and numerically demonstrate a two-dimensional Metal-Dielectric-Metal (MDM) waveguide based on finite-difference time-domain simulation of the propagation characteristics of surface plasmon polaritons (SPPs). For practical applications, we propose a plasmonic Y-branch waveguide based on MDM structure for high integration. The s

  35. P. M. Alsing, G. J. Stephenson, P. Kilian

    We investigate in a covariant manner the spin-induced non-geodesic motion of massive spin 1/2 particles in an arbitrary gravitational field for trajectories that are initially geodesic when spin is ignored. Using the WKB approximation for the wave function in curved spacetime, we compute the O(hbar) correction to the Wigner rotation of the spin 1/2 particle,

  36. R. Walter, N. Cabral

    Aims. The synthesis of the cosmic X-ray background (CXB) requires a large population of Compton-thick active galactic nuclei that have not been detected so far. We probe whether bright infrared galaxies could harbor a population of Compton-thick nuclei and if they could contribute significantly. Methods. We analyzed 112 Msec of INTEGRAL observations obtained

  37. Tomoki Watanabe

    We present a cosmological model in which a single Dirac field with a flat potential can give rise to inflation within the framework of the Einstein-Cartan theory. It is shown that our Dirac-field model leads to a nearly scale-invariant spectrum of density fluctuations owing to the spin-interaction which naturally arises from the field equations of the Einste

  38. Xianshi Lin, Xuguang Huang

    A novel nanometeric plasmonic filter in a tooth-shaped Metal-Insulator-Metal waveguide is proposed and demonstrated numerically. An analytic model based on the scattering matrix method is given. The result reveals that the single tooth-shaped filter has a wavelength filtering characteristic and an ultra-compact size in the length of a few hundred nanometers,

  39. Yue Chan, Ngamta Thamwattana, James M. Hill

    We investigate the motion of a nano tippe top, which is formed from a C60 fullerene, and which is assumed to be spinning on either a graphene sheet or the interior of a single-walled carbon nanotube. We assume no specific geometric configuration for the top, however for example, the nano tippe top might be formed by joining a fullerene C60 with a small segme

  40. Riccardo Fabbri

    The CALICE collaboration has constructed a hadronic sandwich calorimeter prototype with 7608 scintillating plates, individually read out by multi-pixel silicon photomultipliers (SiPMs). For the first time ever the read out is performed using SiPMs on a large scale. Results of test beam operations with muon, positron and hadron beams at CERN are presented her

  41. F. F. Karpeshin

    The effect of the right-left asymmetry is considered in the angular distribution of gamma quanta from fission of U-235 by polarised thermal neutrons, which depends on the polarisation of the neutrons with respect to the gamma-fission plane. Electric dipole radiation from fission fragments arising due to the Strutinsky-Denisov induced polarisation mechanism m

  42. E. Bartos, Yu. M. Bystritskiy, E. A. Kuraev, M. Secansky

    Using the description of the subprocess $γγ^*\to S(P)$ in terms of local Nambu-Jona-Lasinio model we calculate the cross sections of photoproduction of scalar and pseudoscalar mesons in high energy photon-lepton collisions processes. The dependence on the transversal momentum and the total cross sections in Weizsaecker-Williams approximation are presented.

  43. Anouar Saidi

    Let $G$ be a compact subgroup of $GL_n(\R)$ acting linearly on a finite dimensional vector space $E$. B. Malgrange has shown that the space $\mathcal{C}^\infty(\R^n,E)^G$ of $\mathcal{C}^\infty$ and $G$-covariant functions is a finite module over the ring $\mathcal{C}^\infty(\R^n)^G$ of $\mathcal{C}^\infty$ and $G$-invariant functions. First, we generalize t

  44. G. Seibold, J. Lorenzana

    Based on the time-dependent Gutzwiller approximation we study the possibility that the diagonal incommensurate spin scattering in strongly underdoped lanthanum cuprates originates from antiferromagnetic domain walls (stripes). Calculation of the dynamic spin response for stripes in the diagonal phase yields the characteristic hour glass dispersion with the c

  45. Yoshio Kitaoka, Hidekazu Mukuda, Sunao Shimizu

    Extensive Cu-NMR studies on multilayered high-Tc cuprates have deduced the following results;(1) Antiferromagnetic (AFM) moment M_{AFM} is decreased with doping, regardless of the number of CuO_2 layers n, and collapses around a carrier density N_h = 0.17. (2) The AFM ordering temperature is enhanced as the out-of-plane coupling J_{out} increases with increa

  46. Dorota Mozyrska, Delfim F. M. Torres

    We introduce the diamond-alpha exponential function on time scales. As particular cases, one gets both delta and nabla exponential functions. A method of solution of a homogenous linear dynamic diamond-alpha equation on a regular time scale is investigated, and examples of diamond-alpha exponential functions are presented.

  47. A. J. Maury, Ph. André, Z. -Y. Li

    The role played by protostellar feedback in clustered star formation is still a matter of debate. In particular, protostellar outflows have been proposed as a source of turbulence in cluster-forming clumps, which may provide support against global collapse for several free-fall times. Here, we seek to test the above hypothesis in the case of the well-documen

  48. Yuval Emek, Pierre Fraigniaud, Amos Korman, Adi Rosen

    We consider the Work Function Algorithm for the k-server problem. We show that if the Work Function Algorithm is c-competitive, then it is also strictly (2c)-competitive. As a consequence of [Koutsoupias and Papadimitriou, JACM 1995] this also shows that the Work Function Algorithm is strictly (4k-2)-competitive.

  49. W. C. Haxton

    I discuss recent progress in low-energy tests of symmetries and conservation laws, including parity nonconservation in atoms and nuclei, electric dipole moment tests of time-reversal invariance, beta-decay correlation studies, and decays violating separate (family) and total lepton number.

  50. P. Szymczak, A. J. C. Ladd

    We investigate the dissolution of artificial fractures with three-dimensional, pore-scale numerical simulations. The fluid velocity in the fracture space was determined from a lattice-Boltzmann method, and a stochastic solver was used for the transport of dissolved species. Numerical simulations were used to study conditions under which long conduits (wormho

  51. Jun-Hong An, M. Feng, C. H. Oh

    Both cavity QED and photons are promising candidates for quantum information processing. We consider a combination of both candidates with a single photon going through spatially separate cavities to entangle the atomic qubits, based on the input-output process of the cavities. We present a general expression for the input-output process regarding the low-Q

  52. Izumi Umegaki, Toshio Ono, Hidekazu Tanaka, Hidehiro Uekusa

    Elementary excitations of the S=1/2 one-dimensional Heisenberg antiferromagnet KCuGaF$_6$ with exchange constant $J/k_B$=103 K were investigated by high-frequency ESR measurements combined with a pulsed high magnetic field. When an external magnetic field H is applied in KCuGaF$_6$, a staggered magnetic field h is induced perpendicular to H owing to the stag

  53. Jingkun Zhao, Gang Zhao, Yuqin Chen

    Based on the kernel estimator and wavelet technique, we have identified 22 moving group candidates in the solar neighborhood from a sample which includes around 14,000 dwarfs and 6000 giants. Six of them were previously known as the Hercules stream, the Sirus-UMa stream, the Hyades stream, the Caster group, the Pleiades stream, and the IC 2391; five of them

  54. Hung-Chih Chang, Laszlo B. Kish, Maria D. King, Chiman Kwan

    We use the power density spectra obtained by fluctuation-enhanced sensing of bacterial odors (Escherichia coli and Anthrax-surrogate Bacillus subtilis) to generate new, highly distinguishable, types of patterns based on the average slope of the spectra in different frequency ranges. Such plots can be considered as "fingerprints" of bacterial odors. T

  55. Ohad Shemmer, W. N. Brandt, Scott F. Anderson, Aleksandar M. Diamond-Stanic

    We present Chandra observations of nine high-redshift quasars (z=2.7-5.9) discovered by the Sloan Digital Sky Survey with weak or undetectable high-ionization emission lines in their UV spectra (WLQs). Adding archival X-ray observations of six additional sources of this class has enabled us to place the strongest constraints yet on the X-ray properties of th

  56. Carl M. Bender, Philip D. Mannheim

    Despite its common use in quantum theory, the mathematical requirement of Dirac Hermiticity of a Hamiltonian is sufficient to guarantee the reality of energy eigenvalues but not necessary. By establishing three theorems, this paper gives physical conditions that are both necessary and sufficient. First, it is shown that if the secular equation is real, the H

  57. N. S. Narayanaswamy, N. Sadagopan, Apoorve Dubey

    Contraction of an edge merges its end points into a new vertex which is adjacent to each neighbor of the end points of the edge. An edge in a $k$-connected graph is {\em contractible} if its contraction does not result in a graph of lower connectivity. We characterize contractible edges in chordal graphs using properties of tree decompositions with respect t

  58. Huai-Xiang Huang, YouQuan Li

    Motivated by the finding of nearly isotropic superconductivity in $\mathrm{(Ba,K)Fe_2As_2}$, we use renormalized mean field theory to investigated the $t$-$J$ model on three-dimensional simple cubic lattice. A tunable anisotropic parameter is introduced to dictate the coupling on $z$ direction. The symmetry of the superconducting order is studied in detail.

  59. R. I. Grigorchuk, S. V. Ivanov

    We introduce two new types of Dehn functions of group presentations which seem more suitable (than the standard Dehn function) for infinite group presentations and prove the fundamental equivalence between the solvability of the word problem for a group presentation defined by a decidable set of defining words and the property of being computable for one of

  60. Atsushi Moriwaki

    Lazarsfeld and Mustata propose general and systematic usage of Okounkov's idea in order to study asymptotic behavior of linear series on an algebraic variety. It is a very simple way, but it yields a lot of consequences, like Fujita's approximation theorem. Yuan generalized this way to the arithmetic situation, and he established the arithmetic Fujit

  61. D. Hsieh, D. Qian, L. Wray, Y. Xia

    When electrons are subject to a large external magnetic field, the conventional charge quantum Hall effect \cite{Klitzing,Tsui} dictates that an electronic excitation gap is generated in the sample bulk, but metallic conduction is permitted at the boundary. Recent theoretical models suggest that certain bulk insulators with large spin-orbit interactions may

  62. Daniel Farley

    If G is a group acting properly by semisimple isometries on a proper CAT(0) space X, then we build models for the classifying spaces E_{vc} and E_{fbc} under the additional assumption that the action of G has a well-behaved collection of axes in X. (This hypothesis is described in the paper.) We conjecture that the latter hypothesis is satisfied in a large r

  63. Z. F. Xu, R. Q. Wang, L. You

    Heteronuclear molecules attract wide attention due to their permanent electric dipole moments. Analogous to atoms with magnetic dipoles, the existence of nonzero electric dipoles significantly enhance possibilities and mechanisms for control and design of quantum degenerate molecule systems with electric (E-) fields. This work proposes a vortex creation mech

  64. C. Fernández-Córdoba, K. T. Phelps

    The minimum distance graph of an extended Preparata code P(m) has vertices corresponding to codewords and edges corresponding to pairs of codewords that are distance 6 apart. The clique structure of this graph is investigated and it is established that the minimum distance graphs of two extended Preparata codes are isomorphic if and only if the codes are equ

  65. Annika H. G. Peter

    In this last paper in a series of three on weakly interacting massive particle (WIMP) dark matter in the solar system, we focus on WIMPs bound to the system by gravitationally scattering off of planets. We present simulations of WIMP orbits in a toy solar system consisting of only the Sun and Jupiter. As previous work suggested, we find that the density of g

  66. Annika H. G. Peter

    We calculate the annihilation rate of weakly interacting massive particles (WIMPs) in the Sun as a function of their mass and elastic scattering cross section. One byproduct of the annihilation, muon neutrinos, may be observed by the next generation of neutrino telescopes. Previous estimates of the annihilation rate assumed that any WIMPs from the Galactic d

  67. Annika H. G. Peter

    The next generation of dark matter (DM) direct detection experiments and neutrino telescopes will probe large swaths of dark matter parameter space. In order to interpret the signals in these experiments, it is necessary to have good models of both the halo DM streaming through the solar system and the population of DM bound to the solar system. In this pape

  68. Takeshi Kondo, Rustem Khasanov, Tsunehiro Takeuchi, Joerg Schmalian

    A pairing gap and coherence are the two hallmarks of superconductivity. In a classical BCS superconductor they are established simultaneously at Tc. In the cuprates, however, an energy gap (pseudogap) extends above Tc. The origin of this gap is one of the central issues in high temperature superconductivity. Recent experimental evidence demonstrates that the

  69. Paul F. X. Mueller

    We determine the extrapolation law for rearrangement operators of the Haar system on vector valued Hardy spaces.

  70. Adrian Palcu

    In this brief report, apart from the usual approach, we discriminate among models in the class of \textbf{$SU(4)_{L}\otimes U(1)_{Y}$} electro-weak gauge models by just setting the versors in the method of the exactly solving gauge models with high symmetries. We prove that the method itself naturally predicts the correct assingment of the electric charge sp

  71. Pablo Ramacher

    This is the first of a series of papers dealing with the asymptotic behavior of certain integrals occuring in the description of the spectrum of an invariant elliptic operator on a compact Riemannian manifold carrying the action of a compact, connected Lie group of isometries, and in the study of its equivariant cohomology via the moment map.

  72. Lionel Prat, Jerome Rodriguez

    The onset of most microquasar outbursts is characterized by a state transition between a Low/Hard State (LHS) and a High/Soft State (HSS). Besides drastic spectral and timing changes, this transition often shows a discrete ejection event detectable in the radio range. However, the exact nature of the ejected material and the mechanisms that give birth to the

  73. Diego Armentano, Mario Wschebor

    We consider random systems of equations over the reals, with $m$ equations and $m$ unknowns $P_i(t)+X_i(t)=0$, $t\in\mathbb{R}^m$, $i=1,...,m$, where the $P_i$'s are non-random polynomials having degrees $d_i$'s (the "signal") and the $X_i$'s (the "noise") are independent real-valued Gaussian centered random polynomial fields defi

  74. Lauro A. Barbosa, José F. Fontanari

    Axelrod's model for culture dissemination offers a nontrivial answer to the question of why there is cultural diversity given that people's beliefs have a tendency to become more similar to each other's as people interact repeatedly. The answer depends on the two control parameters of the model, namely, the number $F$ of cultural features that ch

  75. David Staszak

    We present measurements of the longitudinal spin asymmetry, $A_{LL}$, for the inclusive jet signal at STAR. The data presented here are mid-rapidity jets in the transverse momentum range of $5<pT<35$ GeV/c and come from polarized proton-proton collisions at center of mass energies of $\sqrt{s}=200$ GeV. We compare our measured $A_{LL}$ values to predictions

  76. A. A. Abdo

    Following its launch in June 2008, the Fermi Gamma-ray Space Telescope (Fermi) began a sky survey in August. The Large Area Telescope (LAT) on Fermi in 3 months produced a deeper and better-resolved map of the gamma-ray sky than any previous space mission. We present here initial results for energies above 100 MeV for the 205 most significant (statistical si

  77. Scott E. Field, Jan S. Hesthaven, Stephen R. Lau

    Gravitational wave emission from extreme mass ratio binaries (EMRBs) should be detectable by the joint NASA-ESA LISA project, spurring interest in analytical and numerical methods for investigating EMRBs. We describe a discontinuous Galerkin (dG) method for solving the distributionally forced 1+1 wave equations which arise when modeling EMRBs via the perturb

  78. Linus Kramer, Richard M Weiss, Jeroen Schillewaert, Koen Struyve

    We prove the following rigidity results. Coarse equivalences between Euclidean buildings preserve spherical buildings at infinity. If all irreducible factors have dimension at least two, then coarsely equivalent Euclidean buildings are isometric (up to scaling factors). If in addition none of the irreducible factors is a Euclidean cone, then the isometry is

  79. V. A. Fateev, A. V. Litvinov, A. Neveu, E. Onofri

    Liouville field theory on a sphere is considered. We explicitly derive a differential equation for four-point correlation functions with one degenerate field $V_{-\frac{mb}{2}}$. We introduce and study also a class of four-point conformal blocks which can be calculated exactly and represented by finite dimensional integrals of elliptic theta-functions for ar

  80. Stephane Chretien, Franck Corset

    The goal of this paper is to survey the properties of the eigenvalue relaxation for least squares binary problems. This relaxation is a convex program which is obtained as the Lagrangian dual of the original problem with an implicit compact constraint and as such, is a convex problem with polynomial time complexity. Moreover, as a main pratical advantage of

  81. Martin Grohe, Goetz Schwandtner

    We study the program complexity of datalog on both finite and infinite linear orders. Our main result states that on all linear orders with at least two elements, the nonemptiness problem for datalog is EXPTIME-complete. While containment of the nonemptiness problem in EXPTIME is known for finite linear orders and actually for arbitrary finite structures, it

  82. Stephan Narison

    This part of the talk aims to present briefly the biodata and the exceptional career of Paco Yndurain who left us suddenly in June 2008. The scientific part: Light Scalar Mesons in QCD is published in the proceedings of QCD 08 (Montpellier 7-12th july 2008: arXiv:0811.0563 [hep-ph]).

  83. Kevin Purbhoo

    The Wronskian associates to d linearly independent polynomials of degree at most n, a non-zero polynomial of degree at most d(n-d). This can be viewed as giving a flat, finite morphism from the Grassmannian Gr(d,n) to projective space of the same dimension. In this paper, we study the monodromy groupoid of this map. When the roots of the Wronskian are real,

  84. S. G. Abaimov

    Many studies investigated the application of statistical mechanics to damage phenomena. However, so far the association of damage with statistical mechanics is far from completely developed. One of the most successful approaches maps the strength elements onto the spins of a lattice. This allows applying the formalism extensively developed for spin systems t

  85. Amit Kashi, Noam Soker

    We study the usage of the X-ray light curve, column density toward the hard X-ray source, and emission measure (density square times volume), of the massive binary system Eta Carinae to determine the orientation of its semi-major axis. The source of the hard X-ray emission is the shocked secondary wind. We argue that, by itself, the observed X-ray flux canno

  86. Timothy Clifton, Pedro G. Ferreira, Joe Zuntz

    It is well known that observations of the cosmic microwave background (CMB) are highly sensitive to the spatial curvature of the Universe, k. Here we find that what is in fact being tightly constrained by small angle fluctuations is spatial curvature near the surface of last scattering, and that if we allow k to be a function of position, rather than taking

  87. Geoffrey R. Robinson

    We prove that for any finite group G, the sum across non-identity elements of the squared absolute value of any generalized character of G which does not vanish on all non-identity elements of G is at least |G|/d -1, where d is the maximal degree of a complex irreducible character of G, and we identify all cases where this minimum possible value is attained.

  88. Xing-Hao Ye

    The electric and magnetic fields are investigated on the basis of quantum vacuum. The analysis of the electromagnetic energy and force indicates that an electric field is a polarized distribution of the vacuum virtual dipoles, and that a magnetic field in vacuum is a rearrangement of the vacuum polarization. It means that an electromagnetic wave is a success

  89. Víctor Blanco, Justo Puerto

    Multiobjective discrete programming is a well-known family of optimization problems with a large spectrum of applications. The linear case has been tackled by many authors during the last years. However, the polynomial case has not been deeply studied due to its theoretical and computational difficulties. This paper presents an algebraic approach for solving

  90. Fu-Ming Liu, Tetsufumi Hirano, Klaus Werner, Yan Zhu

    The transverse momentum (pt) dependence, the centrality dependence and the rapidity dependence of the elliptic flow of thermal photons in Au+Au collisions at $\sqrt{s_{NN}}=200$ GeV are predicted, based on a three-dimensional ideal hydrodynamic description of the hot and dense matter. The elliptic flow parameter $v_{2}$, i.e. the second Fourier coefficient o

  91. P. P. Fiziev

    The Regge-Wheeler equation describes axial perturbations of Schwarzschild metric in linear approximation. Teukolsky Master Equation describes perturbations of Kerr metric in the same approximation. We present here unified description of all classes of exact solutions to these equations in terms of the confluent Heun&#39;s functions. Special attention is paid

  92. Yuan-Jiang Zhang, Gang Li, Qiang Zhao

    We investigate the $ψ(3770)$ non-$D\bar{D}$ decays into $VP$, where $V$ and $P$ denote vector and pseudoscalar mesons, respectively, via OZI-rule-evading intermediate meson rescatterings in an effective Lagrangian theory. By identifying the leading meson loop transitions and constraining the model parameters with the available experimental data for $ψ(3770)\

  93. Izu Vaisman

    If $A$ is a Lie algebroid over a foliated manifold $(M,\mathcal{F})$, a foliation of $A$ is a Lie subalgebroid $B$ with anchor image $T\mathcal{F}$ and such that $A/B$ is locally equivalent with Lie algebroids over the slice manifolds of $\mathcal{F}$. We give several examples and, for foliated Lie algebroids, we discuss the following subjects: the dual Pois

  94. Emily Peters

    Most known examples of subfactors occur in families, coming from algebraic objects such as groups, quantum groups and rational conformal field theories. The Haagerup subfactor is the smallest index finite-depth subfactor which does not occur in one of these families. In this paper we construct the planar algebra associated to the Haagerup subfactor, which pr

  95. Mao-Zhi Yang

    The radiative and leptonic decays of $η_c\to γγ$ and $η_c\to l^+l^-$ are studied. For $η_c\to γγ$ decay, the second-order electromagnetic tree-level diagram gives the leading contribution. The decay rate of $η_c\to γγ$ is calculated, the prediction is in good agreement with the experimental data. For $η_c\to l^+ł^-$, both the tree and loop diagrams are calcu

  96. J. Brian Pitts

    The problem of finding a covariant expression for the distribution and conservation of gravitational energy-momentum dates to the 1910s. A suitably covariant infinite-component localization is displayed, reflecting Bergmann&#39;s realization that there are infinitely many conserved gravitational energy-momenta. Initially use is made of a flat background metr

  97. Alexander Ivanchin

    Modern physics makes wide use of the equation for which only a potential solution is sought. The probability that this equation has a nonpotential solution is omitted from consideration automatically without any explanation. In this paper, using the electron problem as an example, an exact nonpotential solution linearly independent of the classical one is fo

  98. Daniel Hsu, Sham M. Kakade, John Langford, Tong Zhang

    We consider multi-label prediction problems with large output spaces under the assumption of output sparsity -- that the target (label) vectors have small support. We develop a general theory for a variant of the popular error correcting output code scheme, using ideas from compressed sensing for exploiting this sparsity. The method can be regarded as a simp

  99. I. Y. Park

    In arXiv:0801.0218 [hep-th] it was conjectured that quantum effects of open strings moving on D-branes generate the D-brane geometry through a counter-vertex operator. The conjecture has been checked at one-loop in arXiv:0806.3330 [hep-th]. Here we discuss the two-loop extension.

  100. H. Makino, N. Minami, S. Tasaki

    Extending the idea formulated in Makino {\it{et al}}[Phys.Rev.E {\bf{67}},066205], that is based on the Berry--Robnik approach [M.V. Berry and M. Robnik, J. Phys. A {\bf{17}}, 2413], we investigate the statistical properties of a two-point spectral correlation for a classically integrable quantum system. The eigenenergy sequence of this system is regarded as