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June 2008 arXiv papers

Showing 1–100 of 4,915 papers

  1. Daniel G. Figueroa, Licia Verde, Raul Jimenez

    We discuss the cosmological degeneracy between the Hubble parameter H(z), the age of the universe and cosmological parameters describing simple variations from the minimal LCDM model. We show that independent determinations of the Hubble parameter H(z) such as those recently provided by Simon et al., Phys. Rev. D 71 (2005) 123001, combined with Cosmic Microw

  2. Changyong Zhang

    Link weights are the principal parameters of shortest path routing protocols, the most commonly used protocols for IP networks. The problem of optimally setting link weights for unique shortest path routing is addressed. Due to the complexity of the constraints involved, there exist challenges to formulate the problem properly, so that a solution algorithm m

  3. Spencer R. Klein

    IceCube is a 1 km^3 neutrino detector now being built at the Amundsen-Scott South Pole Station. It consists of 4800 Digital Optical Modules (DOMs) which detect Cherenkov radiation from the charged particles produced in neutrino interactions. IceCube will observe astrophysical neutrinos with energies above about 100 GeV. IceCube will be able to separate ν_μ,

  4. Yi-Zhong Fan

    The hypernovae (HNe) associated with Gamma-ray Bursts (GRBs) may have a fairly steep energy-velocity distribution, i.e., $E(\geq β)\propto β^{-q}$ for $q<2$ and $β\geq β_o$, where $β$ is the velocity of the material and $β_o \sim 0.1$ is the velocity of the slowest ejecta of the HN explosion, both in units of the speed of light $(c)$. The cosmic ray protons

  5. M. Hajduk, A. A. Zijlstra, K. Gesicki

    We study the post-AGB central star of the (bipolar) Galactic bulge planetary nebula M 2-29. We have obtained additional HST imaging and SAAO spectroscopy of the object. The star showed a pronounced, long-lasting occultation with subsequent recovery. The event lasted for almost 3 years, with a secondary minimum 9 years later. The photometric behaviour of M 2-

  6. Marko A. Rodriguez, Johan Bollen, Herbert Van de Sompel

    In spite of its tremendous value, metadata is generally sparse and incomplete, thereby hampering the effectiveness of digital information services. Many of the existing mechanisms for the automated creation of metadata rely primarily on content analysis which can be costly and inefficient. The automatic metadata generation system proposed in this article lev

  7. S. M. Gonek, A. H. Ledoan

    We investigate the distribution of the zeros of partial sums of the Riemann zeta-function, sum_{n\leq X}n^{-s}, estimating the number of zeros up to height T, the number of zeros to the right of a given vertical line, and other aspects of their horizontal distribution.

  8. M. Williams, C. A. Meyer

    A common goal in an experimental physics analysis is to extract information from a reaction with multi-dimensional kinematics. The preferred method for such a task is typically the unbinned maximum likelihood method. In fits using this method, the likelihood is a goodness-of-fit quantity in that it effectively discriminates between available hypotheses; howe

  9. Jorge Mondejar, Antonio Pineda

    We consider deep inelastic scattering in the &#39;t Hooft model. Being solvable, this model allows us to directly compute the moments associated with the cross section at next-to-leading order in the 1/Q^2 expansion. We perform the same computation using the operator product expansion. We find that all the terms match in both computations except for one in t

  10. Alberto D. Bolatto, Adam K. Leroy, Erik Rosolowsky, Fabian Walter

    We use high spatial resolution observations of CO to systematically measure the resolved size-line width, luminosity-line width, luminosity-size, and the mass-luminosity relations of Giant Molecular Clouds (GMCs) in a variety of extragalactic systems. Although the data are heterogeneous we analyze them in a consistent manner to remove the biases introduced b

  11. David Eppstein

    We prove that it is NP-complete, given a graph G and a parameter h, to determine whether G contains a complete graph K_h as a minor.

  12. Tilman Enss, Wilhelm Zwerger

    We study the transition to fermion pair superfluidity in a mixture of interacting bosonic and fermionic atoms. The fermion interaction induced by the bosons and the dynamical screening of the condensate phonons due to fermions are included using the nonperturbative Hamiltonian flow equations. We determine the bosonic spectrum near the transition towards phas

  13. Shin&#39;ichiro Ando, Ehud Nakar, Re&#39;em Sari

    We investigate the GeV emission from gamma-ray bursts (GRBs), using the results from the Energetic Gamma Ray Experimental Telescope (EGRET), and in view of the Gamma-ray Large Area Space Telescope (GLAST). Assuming that the conventional prompt and afterglow photons originate from synchrotron radiation, we compare an accompanying inverse-Compton component wit

  14. Suchitra E. Sebastian, J. Gillett, N. Harrison, P. H. C. Lau

    We report quantum oscillation measurements in SrFe2As2 - which is an antiferromagnetic parent of the iron-arsenide family of superconductors - known to become superconducting under doping and the application of pressure. The magnetic field and temperature dependences of the oscillations between 20 and 55 T in the liquid helium temperature range suggest that

  15. Jun Nakabayashi, Daisuke Yamamoto, Susumu Kurihara

    Electric transport of a zigzag graphene nanoribbon through a step-like potential or a barrier potential is investigated by using the recursive Green&#39;s function method. In the case of the step-like potential, we demonstrate numerically that scattering processes obey a selection rule for the band indices when the number of zigzag chains is even; the electr

  16. W. V. Pogosov, V. R. Misko, H. J. Zhao, F. M. Peeters

    We study theoretically the simultaneous effect of a regular and a random pinning potentials on the vortex lattice structure at filling factor of 1. This structure is determined by a competition between the square symmetry of regular pinning array, by the intervortex interaction favoring a triangular symmetry, and by the randomness trying to depin vortices fr

  17. Venkatesh Saligrama

    In this paper we present a new family of discrete sequences having &#34;random like&#34; uniformly decaying auto-correlation properties. The new class of infinite length sequences are higher order chirps constructed using irrational numbers. Exploiting results from the theory of continued fractions and diophantine approximations, we show that the class of se

  18. Kazuo Hosomichi, Ki-Myeong Lee, Sangmin Lee, Sungjay Lee

    We explore further our recent generalization of the $\mathcal{N}=4$ superconformal Chern-Simons theories of Gaiotto and Witten. We find and construct explicitly theories of enhanced $\mathcal{N}=5$ or 6 supersymmetry, especially $\mathcal{N}=5$, $Sp(2M)\times O(N)$ and $\mathcal{N}=6$, $Sp(2M)\times O(2)$ theories. The $U(M)\times U(N)$ theory coincides with

  19. Matthew Daws

    It is shown that the collection of weakly almost periodic functionals on the convolution algebra of a commutative Hopf von Neumann algebra is a C$^*$-algebra. This implies that the weakly almost periodic functionals on $M(G)$, the measure algebra of a locally compact group $G$, is a C$^*$-subalgebra of $M(G)^* = C_0(G)^{**}$. The proof builds upon a factoris

  20. Jason Behrstock, Mladen Bestvina, Matt Clay

    For a fully irreducible automorphism ϕof the free group F_k we compute the asymptotics of the intersection number n \mapsto i(T,T&#39;ϕ^n) for trees T,T&#39; in Outer space. We also obtain qualitative information about the geometry of the Guirardel core for the trees T and T&#39;ϕ^n for n large.

  21. Haiyun Liu, Wentao Zhang, Lin Zhao, Xiaowen Jia

    High resolution angle-resolved photoemission measurements have been carried out on (Sr,K)Fe$_2$As$_2$ superconductor (Tc=21 K). Three hole-like Fermi surface sheets are clearly resolved for the first time around the Gamma point. The overall electronic structure shows significant difference from the band structure calculations. Qualitative agreement between t

  22. Tatsuki Hayama

    In this paper we will study the moduli spaces of log Hodge structures introduced by Kato-Usui. This moduli space is a partial compactification of a discrete quotient of a period domain. We treat the following 2 cases: (A) the case where the period domain is Hermitian symmetric, (B) the case where the Hodge structures are of the mirror quintic type. Especiall

  23. James Bedford, David Berman

    In this note we investigate quantum aspects of the newly proposed theory of multiple membranes put forward by Bagger and Lambert. In particular we analyse the possibility of a finite renormalisation of the coupling at one loop.

  24. Teruhiko Kawano, Masahide Yamaguchi

    A simple model is discussed to give rise to successful reheating in chaotic D-term inflation with a quadratic inflaton potential, introducing a trilinear coupling in the Kähler potential. Leptogenesis through the inflaton decay is also discussed in this model.

  25. Chien Yu Chen

    In this paper, we consider a time dependent module field on spacetime extension without modifying commutative relation on noncommutative quantum plane. The significant idea is that $Lorentz$ symmetry is conserved in module and unmodule coordinate. We focus on the redefinition of spacetime structure without considering noncommutative bosonic gas in deforming

  26. Vivek Mishra, P. J. Hirschfeld, Yu. S. Barash

    We study a toy model for a superconductor on a bipartite lattice, where intrinsic pairing inhomogeneity is produced by two different coupling constants on the sublattices. The simplicity of the model allows for analytic solutions and tests of the consequences of atomic-scale variations in pairing interactions which have been considered recently in the cuprat

  27. Liubin Pan, Paolo Padoan

    To evaluate the effect of turbulent heating in the thermal balance of interstellar clouds, we develop an extension of the log-Poisson intermittency model to supersonic turbulence. The model depends on a parameter, d, interpreted as the dimension of the most dissipative structures. By comparing the model with the probability distribution of the turbulent diss

  28. Andre Gsponer

    The electric and magnetic fields of a pole-dipole singularity attributed to a point-electron-singularity in the Maxwell field are expressed in a Colombeau algebra of generalized functions. This enables one to calculate dynamical quantities quadratic in the fields which are otherwise mathematically ill-defined: The self-energy (i.e., `mass&#39;), the self-ang

  29. Jinsheng Wen, Guangyong Xu, C. Stock, P. M. Gehring

    We present high energy x-ray (67 keV) and neutron scattering measurements on a single crystal of K$_{1-x}$Li$_x$TaO$_3$ for which the Li content ($x=0.02$) is less than $x_c = 0.022$, the critical value below which no structural phase transitions have been reported in zero field. While the crystal lattice does remain cubic down to T=10 K under both zero-fiel

  30. M. Reza Bakhtiari, M. J. Leskinen, P. Torma

    We address an imbalanced two-component atomic Fermi gas restricted by a one-dimensional (1D) optical lattice and an external harmonic potential, within the mean-field Bogoliubov-de Gennes (BdG) formalism. We show that characteristic features of the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state are visible in the RF-spectra and in the momentum resolved photoe

  31. Harald Dimmelmeier, Christian D. Ott, Andreas Marek, Hans-Thomas Janka

    We present results from detailed general relativistic simulations of stellar core collapse to a proto-neutron star, using two different microphysical nonzero-temperature nuclear equations of state as well as an approximate description of deleptonization during the collapse phase. Investigating a wide variety of rotation rates and profiles as well as masses o

  32. Luca de Alfaro, Rupak Majumdar, Vishwanath Raman, Mariëlle Stoelinga

    We consider two-player games played over finite state spaces for an infinite number of rounds. At each state, the players simultaneously choose moves; the moves determine a successor state. It is often advantageous for players to choose probability distributions over moves, rather than single moves. Given a goal, for example, reach a target state, the questi

  33. Gianluca Grignani, Troels Harmark, Marta Orselli

    We examine the string dual of the recently constructed $\mathcal{N}=6$ superconformal Chern-Simons theory of Aharony, Bergman, Jafferis and Maldacena (ABJM theory). We focus in particular on the $SU(2)\times SU(2)$ sector. We find a sigma-model limit in which the resulting sigma-model is two Landau-Lifshitz models added together. We consider a Penrose limit

  34. Andrey Beylin, Thomas L. Curtright, Evgeny Ivanov, Luca Mezincescu

    A Hilbert space metric is found for the SU(2|1)-invariant `superflag&#39; Landau models, parametrized by integer 2N&#39; and real number M, such that the Hilbert space norm is positive definite. The spectrum of these unitary super-Landau models is determined. The M=0 case yields a unitary Landau model on the supersphere SU(2|1)/U(1|1) with U(1) charge 2N=2N&

  35. Eduardo I. Guendelman, Idan Shilon

    We study the properties of a system consisting of an uncharged spherically symmetric two dimensional extended object which encloses a stationary point charge placed in the shell&#39;s center. We show that there can be a static and stable configuration for the neutral shell, using only the gravitational field of the charged source as a stabilizing mechanism.

  36. Marek Karliner

    I discuss several recent highly accurate theoretical predictions for masses of baryons containing the b quark, as well as an effective supersymmetry between heavy quark baryons and mesons. I also suggest some possibilities for observing exotic hadrons containing heavy quarks.

  37. Gleb Arutyunov, Sergey Frolov

    According to the recent proposal by Aharony, Bergman, Jafferis and Maldacena the N=6 supersymmetric Chern-Simons theory in three dimensions has a &#39;t Hooft limit whose holographic dual is described by type IIA superstings on AdS_4 x CP^3 background. We argue that the Green-Schwarz action for type IIA string theory on AdS_4 x CP^3 with kappa-symmetry parti

  38. B. Stefanski

    We present the Green-Schwarz action for Type IIA strings on $AdS_4\times CP^3$. The action is based on a $\Zop_4$ automorphism of the coset $OSp(4|6)/(SO(1,3)\times SU(3)\times U(1))$. The equations of motion admit a representation in terms of a Lax connection, showing that the system is classically integrable.

  39. M. Bashkanov, C. Bargholtz, M. Berlowski, D. Bogoslawsky

    The ABC effect - a puzzling low-mass enhancement in the $ππ$ invariant mass spectrum - is well-known from inclusive measurements of two-pion production in nuclear fusion reactions. Here we report on first exclusive and kinematically complete measurements of the most basic double pionic fusion reaction $pn \to d π^0π^0$ at 1.03 and 1.35 GeV. The measurements,

  40. D. L. Gonzalez, G. Tellez

    We study numerically the crossover between organized and disorganized states of three non-equilibrium systems: the Poisson/coalesce random walk (PCRW), a one-dimensional spin system and a quasi one-dimensional lattice gas. In all cases, we describe this crossover in terms of the average spacing between particles/domain borders $< S(t) >$ and the spacing dist

  41. Neil V. Budko

    Since the 1983 definition of the speed of light in vacuum as a fundamental constant with the exact value of 299792458 m/s the question remains as to what apart from the wavefront travels at that speed. It is commonly assumed that the entire wave-packet or an impulse of the electromagnetic radiation in free space does. Here it is shown, both theoretically and

  42. Toshifumi Itakura

    In this study, we examine decoherence of qubits system coupled independently by using influence functional. We especially concentrated on the effect of qubit flip process. We examine the zero-dimensional qubit and one-dimensional qubits system coupled with multi-band one-dimensional system. The qubit flip process leads to oscillation and self-excitation. We

  43. Bruno Galvan

    A new formulation of quantum mechanics is proposed based on a new principle that can be considered a generalization of the Born rule. The principle is composed of a mathematical expression and an associated interpretation, and establishes a correlation between the positions of a particle at two different times. Under reasonable conditions for the wave functi

  44. Xiao-Hui Bao, Yong Qian, Jian Yang, Han Zhang

    We report an experimental realization of a narrow-band polarization-entangled photon source with a linewidth of 9.6 MHz through cavity-enhanced spontaneous parametric down-conversion. This linewidth is comparable to the typical linewidth of atomic ensemble based quantum memories. Single-mode output is realized by setting a reasonable cavity length difference

  45. S. J. van Enk

    I consider two identical quantum particles in two boxes. We can split each box, and thereby the wavefunction of each particle, into two parts. When two half boxes are interchanged and combined with the other halves, where do the two particles end up? I solve this problem for two identical bosons and for two identical fermions. The solution can be used to def

  46. Michael Schmidt, Thomas Hornung, Georg Lausen, Christoph Pinkel

    Recently, the SPARQL query language for RDF has reached the W3C recommendation status. In response to this emerging standard, the database community is currently exploring efficient storage techniques for RDF data and evaluation strategies for SPARQL queries. A meaningful analysis and comparison of these approaches necessitates a comprehensive and universal

  47. Akinobu Doté, Tetsuo Hyodo, Wolfram Weise

    The ppK^- system, as a prototype for possible quasibound Kbar nuclei,is investigated using a variational approach. Several versions of energy dependent effective KbarN interactions derived from chiral SU(3) dynamics are employed as input, together with a realistic NN potential (Av18). Taking into account theoretical uncertainties in the extrapolations below

  48. Thomas Belhadj, Takashi Kuroda, Claire-Marie Simon, Thierry Amand

    We report optical orientation experiments in individual, strain free GaAs quantum dots in AlGaAs grown by droplet epitaxy. Circularly polarized optical excitation yields strong circular polarization of the resulting photoluminescence at 4K. Optical injection of spin polarized electrons into a dot gives rise to dynamical nuclear polarization that considerably

  49. Takahiro Azuma, Takao Koikawa

    We study the 5D static Einstein-Maxwell equations with a dilaton field. We construct an infinte number of solutions by using a soliton technique. We study the rod structure of 2-soliton solution and show the 5D dilatonic black ring and black hole solutions are included.

  50. R. Bonciani, A. Ferroglia

    We briefly review the status of the calculation of next-to-next-to-leading order corrections to large angle Bhabha scattering in pure QED. In particular, we focus on the analytic calculation of the two-loop virtual corrections involving a heavy-flavor fermion loop, which was recently completed. We conclude by assessing the numerical impact of these correctio

  51. Roberto Benzi, Luca Biferale, Enrico Calzavarini, Detlef Lohse

    We present an investigation of the statistics of velocity gradient related quantities, in particluar energy dissipation rate and enstrophy, along the trajectories of fluid tracers and of heavy/light particles advected by a homogeneous and isotropic turbulent flow. The Refined Similarity Hypothesis (RSH) proposed by Kolmogorov and Oboukhov in 1962 is rephrase

  52. Robert S. Whitney

    We consider a two-level system coupled to a highly non-Markovian environment when the coupling axis rotates with time. The environment may be quantum (for example a bosonic bath or a spin bath) or classical (such as classical noise). We show that an Anderson orthogonality catastrophe suppresses transitions, so that the system&#39;s instantaneous eigenstates

  53. P. Moskalik, A. Olech

    We have conducted a systematic search for multiperiodic pulsations in the RR Lyrae-type stars of the galactic globular cluster Omega Cen. Secondary periodicities close to the primary pulsation frequency have been detected in 17 out of 70 studied fundamental mode (RRab) pulsators and in 35 out of 81 overtone (RRc) pulsators. Because of the observed period rat

  54. Johan Nilsson, A. R. Akhmerov, C. W. J. Beenakker

    Majorana bound states are spatially localized superpositions of electron and hole excitations in the middle of a superconducting energy gap. A single qubit can be encoded nonlocally in a pair of spatially separated Majorana bound states. Such Majorana qubits are in demand as building blocks of a topological quantum computer, but direct experimental tests of

  55. Emanuel Gluskin

    (Abbr.) We consider a direct representation of a periodic time-function by means of its zero-crossings. The use of the zero-crossings as the describing parameters is made possible by a singular model of a strongly nonlinear electrical element. This new method is found helpful in the calculation and synthesis of a practically important system, and deserves at

  56. N. Ya. Ivanov, B. A. Kniehl

    We analyze the perturbative and parametric stability of the QCD predictions for the Callan-Gross ratio $R(x,Q^2)=F_L/F_T$ in heavy-quark leptoproduction. We consider the radiative corrections to the dominant photon-gluon fusion mechanism. In various kinematic regions, the following contributions are investigated: exact NLO results at low and moderate $Q^2\le

  57. Heng-Dong Xi, Sheng-Qi Zhou, Quan Zhou, Tak-Shing Chan

    We report an experimental study of the three-dimensional spatial structure of the low frequency temperature oscillations in a cylindrical Rayleigh-Bénard convection cell. It is found that thermal plumes are not emitted periodically, but randomly and continuously, from the top and bottom plates. We further found that the oscillation of the temperature field d

  58. C. de Kerchove, G. Krings, R. Lambiotte, V. D. Blondel

    We study the propagation of information in social networks. To do so, we focus on a cascade model where nodes are infected with {probability $p_1$ after their first contact with the information and with probability $p_2$ at all subsequent contacts.} The diffusion starts from one random node and leads to a cascade of infection. It is shown that first and {sub

  59. Anna Szczypinska, Edward W. Piotrowski

    In this paper we propose a method for a quantitative estimation of the decision maker&#39;s knowledge in the context of the Analytic Hierarchy Process (AHP) in cases, where the judgment matrix is inconsistent. We show that the matrix of deviation from the transitivity condition corresponds to the rate matrix for transaction costs in the financial market. For

  60. Laszlo Erdos, Benjamin Schlein, Horng-Tzer Yau

    Consider $N$ bosons in a finite box $Λ= [0,L]^3\subset \bR^3$ interacting via a two-body nonnegative soft potential $V= λ\tilde V$ with $\tilde V$ fixed and $λ>0$ small. We will take the limit $L, N \to \infty$ by keeping the density $\varrho= N/L^{3}$ fixed and small. We construct a variational state which gives an upper bound on the ground state energy per

  61. C. Figueira de Morisson Faria, T. Shaaran, X. Liu, W. Yang

    We address the influence of the orbital symmetry and of the molecular alignment with respect to the laser-field polarization on laser-induced nonsequential double ionization of diatomic molecules, in the length and velocity gauges. We work within the strong-field approximation and assume that the second electron is dislodged by electron-impact ionization, an

  62. Roland Knevel

    Aim of this article is a Satake type theorem for super automorphic forms on a complex bounded symmetric super domain B of rank 1 with respect to a lattice. This theorem - roughly speaking - says that for large weight k and all p from 1 to infinity (both including) a super automorphic form on B is a super cusp form if and only if its p-norm with respect to a

  63. Salim Bouzebda, Amor Keziou

    We introduce new estimates and tests of independence in copula models with unknown margins using $ϕ$-divergences and the duality technique. The asymptotic laws of the estimates and the test statistics are established both when the parameter is an interior or a boundary value of the parameter space. Simulation results show that the choice of $χ^2$-divergence

  64. Sinya Aoki, Oliver Bar, Benedikt Biedermann

    We compute the scattering amplitude for pion scattering in Wilson chiral perturbation theory for two degenerate quark flavors. We consider two different regimes where the quark mass m is of order (i) aΛ_QCD^2 and (ii) a^2Λ_QCD^3. Analytic expressions for the scattering lengths in all three isospin channels are given. As a result of the O(a^2) terms the I=0 a

  65. Reza Moazzemi, Abdollah Mohammadi, Siamak S. Gousheh

    In this paper we discuss the effects of nontrivial boundary conditions or backgrounds, including non-perturbative ones, on the renormalization program for systems in two dimensions. Here we present an alternative renormalization procedure such that these non-perturbative conditions can be taken into account in a self-contained and, we believe, self-consisten

  66. Zbigniew Walczak

    In quantum information theory it is generally accepted that quantum mutual information is an information-theoretic measure of total correlations of a bipartite quantum state. We argue that there exist quantum states for which quantum mutual information cannot be considered as a measure of total correlations. Moreover, for these states we propose a different

  67. G. Sonne, L. Y. Gorelik, S. I. Kulinich, R. I. Shekhter

    We demonstrate that a supercurrent can pump energy from a battery that provides a voltage bias into nanomechanical vibrations. Using a device containing a nanowire Josephson weak link as an example we show that a nonlinear coupling between the supercurrent and a static external magnetic field leads to a Lorentz force that excites bending vibrations of the wi

  68. Stéphane Lengrand

    In this paper we prove that any lambda-term that is strongly normalising for beta-reduction is also strongly normalising for beta,assoc-reduction. assoc is a call-by-value rule that has been used in works by Moggi, Joachimsky, Espirito Santo and others. The result has often been justified with incomplete or incorrect proofs. Here we give one in full details.

  69. Aline Bonami, Justin Feuto

    We define as a distribution the product of a function (or distribution) h in some Hardy space Hp with a function b in the dual space of Hp. Moreover, we prove that the product bxh may be written as the sum of an integrable function with a distribution that belongs to some Hardy-Orlicz space, or to the same Hardy space Hp, depending on the values of p.

  70. David A. Herrera-Martí

    The Separability Problem is approached from the perspective of Ellipsoidal Classification. A Density Operator of dimension N can be represented as a vector in a real vector space of dimension $N^{2}- 1$, whose components are the projections of the matrix onto some selected basis. We suggest a method to test separability, based on successive optimization prog

  71. Evgeny Feigin

    Let $L$ be the basic (level one vacuum) representation of the affine Kac-Moody Lie algebra $\hat{\mathfrak g}$. The $m$-th space $F_m$ of the PBW filtration on $L$ is a linear span of vectors of the form $x_1... x_lv_0$, where $l\le m$, $x_i\in \hat{\mathfrak g}$ and $v_0$ is a highest weight vector of $L$. In this paper we give two descriptions of the assoc

  72. Slimane Benelkourchi

    We study the complex Monge-Ampre operator on the classes of finite pluricomplex energy $\mathcal{E}_χ(Ω)$ in the general case ($χ(0)=0$ i.e. the total Monge-Ampre mass may be infinite). We establish an interpretation of these classes in terms of the speed of decrease of the capacity of sublevel sets and give a complete description of the range of the operato

  73. Bum Suk Zhao, Stephan A. Schulz, Samuel A. Meek, Gerard Meijer

    We observe high-resolution diffraction patterns of a thermal-energy helium-atom beam reflected from a microstructured surface grating at grazing incidence. The grating consists of 10-$μ$m-wide Cr strips patterned on a quartz substrate and has a periodicity of 20 $μ$m. Fully-resolved diffraction peaks up to the $7^{\rm th}$ order are observed at grazing angle

  74. Avni Pllana, Herbert Bauer

    In this paper we present a new localization method SMS-LORETA (Simultaneous Multiple Sources- Low Resolution Brain Electromagnetic Tomography), capable to locate efficiently multiple simultaneous sources. The new method overcomes some of the drawbacks of sLORETA (standardized Low Resolution Brain Electromagnetic Tomography). The key idea of the new method is

  75. M. Kuźniak, I. Altarev, G. Ban, G. Bison

    A new measurement of the neutron EDM, using Ramsey&#39;s method of separated oscillatory fields, is in preparation at the new high intensity source of ultra-cold neutrons (UCN) at the Paul Scherrer Institute, Villigen, Switzerland (PSI). The existence of a non-zero nEDM would violate both parity and time reversal symmetry and, given the CPT theorem, might le

  76. Wen-ge Wang

    The standard formalism of quantum mechanics is extended to describe a total system including the reference system (RS), with respect to which the total system is described. The RS is assumed to be able to act as a measuring apparatus, with measurement records given by the values of some reference properties of the RS. In order to describe the total system, w

  77. Antonio Deiana, Andrea Giansanti

    The performance of single folding predictors and combination scores is critically evaluated. We test mean packing, mean pairwise energy and the new index gVSL2 on a dataset of 743 folded proteins and 81 natively unfolded proteins. These predictors have an individual performance comparable or even better than other proposed methods. We introduce here a strict

  78. Florentin Millour, Romain Petrov, Martin Vannier, Stefan Kraus

    The first astrophysical results of the VLTI focal instrument AMBER have shown the importance of the differential and closure phase measures, which are supposed to be much less sensitive to atmospheric and instrumental biases than the absolute visibility. However there are artifacts limiting the accuracy of these measures which can be substantially overcome b

  79. Yasufumi Hashimoto

    It is known that the Selberg zeta function for the modular group has an expression in terms of the class numbers and the fundamental units of the indefinite binary quadratic forms. In the present paper, we generalize such a expression to any congruence subgroup of the modular groups in SL(2,R) and SL(2,C).

  80. Austin G. Fowler

    We describe in detail how to perform universal fault-tolerant quantum computation on a 2-D color code, making use of only nearest neighbor interactions. Three defects (holes) in the code are used to represent logical qubits. Triple defect logical qubits are deformed into isolated triangular sections of color code to enable transversal implementation of all s

  81. R. Horvat

    Holographic dark energy (HDE) models, underlain by an effective quantum field theory (QFT) with a manifest UV/IR connection, have become a convincing candidate for the dark energy in the universe. On the other hand, the maximum number of quantum states a conventional QFT in the box of size $L$ is capable to describe, refer to those boxes which are on the bri

  82. A. Malizia, L. Bassani, A. J. Bird, R. Landi

    Narrow Line Seyfert 1 galaxies (NLS1) are very interesting objects which display peculiar properties when compared to their broad line analogues (BLS1). Although well studied in many wavebands, their behaviour at >10 keV is poorly studied and yet important to discriminate between models invoked to explain the complexity observed in the X-ray band. Here we pr

  83. Anirudh Pradhan, Priya Mathur

    A new class of cylindrically symmetric inhomogeneous cosmological models for perfect fluid distribution with electromagnetic field is obtained in the context of Lyra&#39;s geometry. We have obtained two types of solutions by considering the uniform as well as time dependent displacement field. The source of the magnetic field is due to an electric current pr

  84. Yu. G. Naidyuk, G. Behr, N. L. Bobrov, V. N. Chernobay

    An general survey of the superconducting (SC) gap study in the title compounds by point-contact (PC) spectroscopy is presented. The SC gap was determined from dV/dI of PCs employing the well-known theory of conductivity for normal metal-superconductor PCs accounting Andreev reflection. The theory was modified by including pair-breaking effects considering th

  85. M. Kreps

    We review recent experimental results on direct CP violation. The hot topic is a measurement in charmless two-body decays of B0, B+. In connection to this the first analogous measurements in Bs0 and Lambda_b0 decays are now available. Furthermore first evidence for direct CP violation in B+ decays is obtained from Dalitz plot analyzes of the K+pi-pi+ final s

  86. Alioscia Hamma, Toufik Mansour, Simone Severini

    We count the number of histories between the two degenerate minimum energy configurations of the Ising model on a chain, as a function of the length n and the number d of kinks that appear above the critical temperature. This is equivalent to count permutations of length n avoiding certain subsequences depending on d. We give explicit generating functions an

  87. Toufik Mansour, Simone Severini

    It is known that the Hilbert space dimensionality for quasiparticles in an SU(2)_k Chern-Simons-Witten theory is given by the number of directed paths in certain Bratteli diagrams. We present an explicit formula for these numbers for arbitrary k. This is on the basis of a relation with Dyck paths and Chebyshev polynomials.

  88. Changhyun Ahn

    As we re-examine the known holographic N=1 supersymmetric renormalization group flow in four dimensions, we describe the mass-deformed Bagger-Lambert theory or equivalently the mass-deformed U(2) x U(2) Chern-Simons gauge theory with level k=1 or 2, that has G_2 symmetry, by adding a mass term for one of the eight adjoint superfields. We obtain a detailed co

  89. Charles C. Kankelborg

    A simple, yet powerful, algorithm for computed tomography of the solar corona is presented and demonstrated using synthetic EUV data. A minimum of three perspectives are required. These may be obtained from STEREO/EUVI plus an instrument near Earth, e.g. TRACE or SOHO/EIT.

  90. S. Takeshita, R. Kadono, M. Hiraishi, M. Miyazaki

    Recent discovery of oxypnictide superconductor LaFeAs(O,F) (LFAO-F) with the critical temperature (Tc) of 26 K and succeeding revelation of much increased Tc upon substitution of La for other rare earth elements (such as Sm, leading to ~43 K) and application of pressure for LFAO-F (~ 43 K) has triggered broad interest in the mechanism yielding relatively hig

  91. X. C. Wang, Q. Q. Liu, Y. X. Lv, W. B. Gao

    A new iron arsenide superconducting system LiFeAs was found that crystallizes into a tetragonal structure with space group P4/nmm. The superconductivity with Tc up to 18 K was observed in the compounds. This simple 111 type layered iron arsenide superconductor can be viewed as an analogue of the infinite layer structure of copper oxides.

  92. R. Berman, S. Boucksom

    We prove the several variable version of the classical equidistribution theorem for Fekete points of a compact subset of the complex plane, which settles a well-known conjecture in pluri-potential theory. The result is obtained as a special case of a general equidistribution theorem for Fekete points in the setting of a given holomorphic line bundle over a c

  93. T. Senthil, R. Shankar

    Traditionally Fermi surfaces for problems in $d$ spatial dimensions have dimensionality $d-1$, i.e., codimension $d_c=1$ along which energy varies. Situations with $d_c >1$ arise when the gapless fermionic excitations live at isolated nodal points or lines. For $d_c > 1$ weak short range interactions are irrelevant at the non-interacting fixed point. Increas

  94. V. M. Akulin, Yu. E. Lozzovik, I. E. Mazets, A. G. Rudavets

    We consider interaction of an electron with a Bose condensate of atoms having electron affinity. Though states of the electron attached to atoms form a continuous band, tunneling through this band is strongly suppressed by quantum fluctuations of the condensate density. We adapt standard field theory methods originally developed for description of a particle

  95. Gilles Halbout, Jean-Michel Oudom, Xiang Tang

    Let $Γ$ be a finite group acting faithfully and linearly on a vector space $V$. Let $T(V)$ ($S(V)$) be the tensor (symmetric) algebra associated to $V$ which has a natural $Γ$ action. We study generalized quadratic relations on the tensor algebra $T(V)\rtimes Γ$. We prove that the quotient algebras of $T(V)\rtimes Γ$ by such relations satisfy PBW property. S

  96. Juan M. Uson, W. D. Cotton

    Radio telescopes with off-axis feeds, such as the (E)VLA, suffer from &#34;beam squint&#34; in which the two orthogonal circular polarizations sampled have different pointing centers on the sky. Its effects are weak near the beam center but become increasingly important towards the edge of the antenna power pattern where gains in the two polarizations at a g

  97. S. Bruce

    We present a nonrelativistic wave equation for the electron in (3+1)-dimensions which includes negative-energy eigenstates. We solve this equation for three well-known instances, reobtaining the corresponding Pauli equation (but including negative-energy eigenstates) in each case.

  98. T. Binoth, N. Kauer, P. Mertsch

    A calculation of the loop-induced gluon-fusion process gg --> Z(photon)Z(photon) --> l anti-l l&#39; anti-l&#39; is presented, which provides an important background for Higgs boson searches in the H --> ZZ channel at the LHC. We find that the photon contribution is important for Higgs masses below the Z-pair threshold and that the gg-induced process yields

  99. S. C. Lim, L. P. Teo

    Two types of Gaussian processes, namely the Gaussian field with generalized Cauchy covariance (GFGCC) and the Gaussian sheet with generalized Cauchy covariance (GSGCC) are considered. Some of the basic properties and the asymptotic properties of the spectral densities of these random fields are studied. The associated self-similar random fields obtained by a

  100. Gregory Soyez

    We illustrate how the midpoint and iterative cone (with progressive removal) algorithms fail to satisfy the fundamental requirements of infrared and collinear safety, causing divergences in the perturbative expansion. We introduce SISCone and the anti-kt algorithms as respective replacements that do not have those failures without any cost at the experimenta