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July 2009 arXiv papers — page 39

Showing 3,8013,900 of 5,590 papers

  1. Aaron Torok, Silas R. Beane, William Detmold, Thomas C Luu

    The $π^+Σ^+$, $π^+Ξ^0$, $K^+p$, $K^+n$, and $\overline{K}{}^0 Ξ^0$ scattering lengths are calculated in mixed-action Lattice QCD with domain-wall valence quarks on the asqtad-improved coarse MILC configurations at four light-quark masses, and at two light-quark masses on the fine MILC configurations. Heavy Baryon Chiral Perturbation Theory with two and three

  2. Guido D'Amico, Marc Kamionkowski, Kris Sigurdson

    These lectures are intended to provide a brief pedagogical review of dark matter for the newcomer to the subject. We begin with a discussion of the astrophysical evidence for dark matter. The standard weakly-interacting massive particle (WIMP) scenario--the motivation, particle models, and detection techniques--is then reviewed. We provide a brief sampling o

  3. Taras V. Siversky, Valentina V. Zharkova

    In this work we study time-dependent precipitation of an electron beam injected into a flaring atmosphere with a converging magnetic field by considering collisional and Ohmic losses with anisotropic scattering and pitch angle diffusion. Two injection regimes are investigated: short impulse and stationary injection. The effects of converging magnetic fields

  4. Justas Kalpokas, Jörn Steuding

    We investigate the intersections of the curve $\mathbb{R}\ni t\mapsto ζ({1\over 2}+it)$ with the real axis. We show that if the Riemann hypothesis is true, the mean-value of those real values exists and is equal to 1. Moreover, we show unconditionally that the zeta-function takes arbitrarily large real values on the critical line.

  5. Artur B. Adib

    It has recently been argued that a self-consistency condition involving the Jarzynski equality (JE) and the Crooks fluctuation theorem (CFT) is violated for a simple Brownian process [L. Y. Chen, J. Chem. Phys. 129, 091101 (2008)]. This note adopts the definitions in the original formulation of the JE and CFT and demonstrates the contrary.

  6. Zhanhua Ma, Sunil Ahuja, Clarence W. Rowley

    In feedback flow control, one of the challenges is to develop mathematical models that describe the fluid physics relevant to the task at hand, while neglecting irrelevant details of the flow in order to remain computationally tractable. A number of techniques are presently used to develop such reduced-order models, such as proper orthogonal decomposition (P

  7. Irakli Patchkoria

    We introduce pseudocubical objects with pseudoconnections in an arbitrary category, obtained from the Brown-Higgins structure of a cubical object with connections by suitably relaxing their identities, and construct a cubical analog of the Tierney-Vogel theory of simplicial derived functors. The crucial point in the construction is that projective precubical

  8. Tesla E. Jeltema, Brian F. Gerke, Elise S. Laird, Christopher N. A. Willmer

    We present the discovery of seven X-ray emitting groups of galaxies selected as extended X-ray sources in the 200 ksec Chandra coverage of the All-wavelength Extended Groth Strip International Survey (AEGIS). In addition, we report on AGN activity associated to these systems. Using the DEEP2 Galaxy Redshift Survey coverage, we identify optical counterparts a

  9. Kevin T. McCusker, Paul G. Kwiat

    We discuss a novel method of efficiently producing multi-photon states using repeated spontaneous parametric downconversion. Specifically, by attempting downconversion several times, we can pseudo-deterministically add photons to a mode, producing various several-photon states. We discuss both expected performance and experimental limitations.

  10. N. Dubrovinskaia, L. Dubrovinsky, E. Yu. Zarechnaya, Y. Filinchuk

    Oganov et al report a discovery of an ionic high-pressure /hitherto unknown phase of boron/. We show that this phase has been known since 1965, and it is a covalent material.

  11. Ralph Schoenrich, James Binney

    We examine the chemical and dynamical structure in the solar neighbourhood of a model Galaxy that is the endpoint of a simulation of the chemical evolution of the Milky Way in the presence of radial mixing of stars and gas. Although the simulation's star-formation rate declines monotonically from its unique peak and no merger or tidal event ever takes pl

  12. E. Fernandez-Lajus, C. Farina, J. P. Calderon, N. Salerno

    The periodic events occurring in Eta Carinae have been widely monitored during the last three 5.5-year cycles. The last one recently occurred in January 2009 and more exhaustive observations have been made at different wavelength ranges. If these events are produced when the binary components approach periastron, the timing and sampling of the photometric fe

  13. Patrick Huber, Manfred Lindner, Thomas Schwetz, Walter Winter

    We compare the physics potential of the upcoming neutrino oscillation experiments Daya Bay, Double Chooz, NOvA, RENO, and T2K based on their anticipated nominal luminosities and schedules. After discussing the sensitivity to theta_{13} and the leading atmospheric parameters, we demonstrate that leptonic CP violation will hardly be measurable without upgrades

  14. A. Ianni, G. Pagliaroli, A. Strumia, F. R. Torres

    We derive the event-by-event likelihood that allows to extract the complete information contained in the energy, time and direction of supernova neutrinos, and specify it in the case of SN1987A data. We resolve discrepancies in the previous literature, numerically relevant already in the concrete case of SN1987A data.

  15. Pierre Mounoud

    In this article we extend the Gallot-Tanno theorem to closed pseudo-Riemannian manifolds. It is done by showing that if the cone over such a manifold admits a parallel symmetric 2-tensor then it is incomplete and has non zero constant curvature. An application of this result to the existence of metrics with distinct Levi-Civita connections but having the sam

  16. Syed T. Qaseem, Tareq Y. Al-Naffouri

    We propose a generalized feedback model and compressive sensing based opportunistic feedback schemes for feedback resource reduction in MIMO Broadcast Channels under the assumption that both uplink and downlink channels undergo block Rayleigh fading. Feedback resources are shared and are opportunistically accessed by users who are strong, i.e. users whose ch

  17. S. G. Schirmer, P. J. Pemberton-Ross

    Spin chains have been proposed as quantum wires for information transfer in solid state quantum architectures. We show that huge gains in both transfer speed and fidelity are possible using a minimalist control approach that relies only a single, local, on-off switch actuator. Effective switching time sequences can be determined using optimization techniques

  18. Krzysztof M. Graczyk, D. Kielczewska, Jan T. Sobczyk

    $C_5^A(Q^2)$ axial form factor is extracted from the ANL neutrino-deuteron scattering data with deuteron structure effects taken into consideration. The best fit of the $C_5^A(Q^2)$ axial form factor is obtained assuming dipole parametrization with $C_5^A(0)=1.13\pm0.15$ and $M_A=0.94\pm 0.08$ GeV.

  19. L. W. Lupinski, M. J. Madsen

    We investigate the angular normal modes for small oscillations about an equilibrium of a single-component coulomb cluster confined by a radially symmetric external potential to a circle. The dynamical matrix for this system is a Laplacian symmetrically circulant matrix and this result leads to an analytic solution for the eigenfrequencies of the angular norm

  20. Jon Tyson

    We compare several instances of pure-state Belavkin weighted square-root measurements from the standpoint of minimum-error discrimination of quantum states. The quadratically weighted measurement is proven superior to the so-called "pretty good measurement" (PGM) in a number of respects: (1) Holevo's quadratic weighting unconditionally outperform

  21. Bart De Pontieu, Viggo H. Hansteen, Scott W. McIntosh, Spiros Patsourakos

    Many models for coronal loops have difficulty explaining the observed EUV brightness of the transition region, which is often significantly less than theoretical models predict. This discrepancy has been addressed by a variety of approaches including filling factors and time-dependent heating. Here we focus on an effect that has been ignored so far: the abso

  22. Nigel T. Bishop, Amos S. Kubeka

    We investigate perturbations of the Schwarzschild geometry using a linearization of the Einstein vacuum equations within a Bondi-Sachs, or null cone, formalism. We develop a numerical method to calculate the quasi-normal modes, and present results for the case $\ell=2$. The values obtained are different to those of a Schwarzschild black hole, and we interpre

  23. Donald Yau

    A class of non-associative and non-coassociative generalizations of cobraided bialgebras, called cobraided Hom-bialgebras, is introduced. The non-(co)associativity in a cobraided Hom-bialgebra is controlled by a twisting map. Several methods for constructing cobraided Hom-bialgebras are given. In particular, Hom-type generalizations of FRT quantum groups, in

  24. Gero Friesecke, Mario Koppen

    We give a mathematically rigorous derivation of Ehrenfest's equations for the evolution of position and momentum expectation values, under general and natural assumptions which include atomic and molecular Hamiltonians with Coulomb interactions.

  25. Siming Liu, Lyndsay Fletcher

    Most theoretical investigations of particle acceleration during solar flares cannot be applied to observations for detailed study of the time evolution. We propose a phenomenological model for turbulence evolution and stochastic particle acceleration that links observations to the energy release and particle acceleration through two coefficients characterizi

  26. A. V. Nikulov

    It is shown that the assumptions on macroscopic quantum tunneling and on superposition of two macroscopically distinct quantum states of superconducting loop, considered as flux qubit by many authors, contradict to the fundamental law of angular momentum conservation and the universally recognized quantum formalism.

  27. Paolo Giordano

    F.: Good morning Hermann, I would like to talk with you about infinitesimals. G.: Tell me Pierre. F.: I'm fed up of all these slanders about my attitude to be non rigorous, so I've started to study nonstandard analysis (NSA) and synthetic differential geometry (SDG). G.: Yes, I've read something ... F.: Ok, no problem about their rigour. But, whe

  28. Shumin Xiao, Uday K. Chettiar, Alexander V. Kildishev, Vladimir Drachev

    We demonstrate a thermally tunable optical metamaterial with negative permeability working in the visible range. By covering coupled metallic nanostrips with aligned nematic liquid crystals (NLCs), the magnetic response wavelength of the metamaterial is effectively tuned through control of the ambient temperature, changing the refractive index of LC via phas

  29. Shumin Xiao, Uday K. Chettiar, Alexander V. Kildishev, Vladimir P. Drachev

    A well-established, silver fishnet design has been further miniaturized to function as a negative-index material at the shortest wavelength to date. By studying the transmittance, reflectance, and corresponding numerical simulations of the sample, we report in this paper a negative refractive index of -0.25 at the yellow-light wavelength of 580 nm.

  30. James E. Davidheiser, Paul Syers, P. N. Segrè, Eric R. Weeks

    Numerous studies have demonstrated the potential for simple fluid plus particle systems to produce complicated dynamical behavior. In this work, we study a horizontal rotating drum filled with pure glycerol and three large, heavy spheres. The rotation of the drum causes the spheres to cascade and tumble and thus interact with each other. We find several diff

  31. Carlos E. Fiore, Marcia Szortyka, Marcia C. Barbosa, Vera B. Henriques

    The Bell-Lavis model for liquid water is investigated through numerical simulations. The lattice-gas model on a triangular lattice presents orientational states and is known to present a highly bonded low density phase and a loosely bonded high density phase. We show that the model liquid-liquid transition is continuous, in contradiction with mean-field resu

  32. J. P. Home, D. Hanneke, J. D. Jost, J. M. Amini

    Large-scale quantum information processors must be able to transport and maintain quantum information, and repeatedly perform logical operations. Here we demonstrate a combination of all the fundamental elements required to perform scalable quantum computing using qubits stored in the internal states of trapped atomic ions. We quantify the repeatability of a

  33. I. V. Bondarev

    The article reviews recent progress in the theoretical understanding of near-field surface electromagnetic phenomena in pristine and atomically doped carbon nanotubes. The phenomena involving strong coupling effects are outlined. They are the optical absorption by single-walled carbon nanotubes doped with single atoms or ions in the frequency range close to

  34. A. Chiavassa, B. Plez, E. Josselin, B. Freytag

    Context. It has been suggested that convection in Red Supergiant (RSG) stars gives rise to large-scale granules causing observable surface inhomogeneities. This convection is also extremely vigorous, and suspected to be one of the causes of mass-loss in RSGs. It must thus be understood in details. Evidence has been accumulated that there are asymmetries in t

  35. Xuesong Li, Weiwei Cai, Luigi Colombo, Rodney S. Ruoff

    Large-area graphene is a new material with properties that make it desirable for advanced scaled electronic devices1. Recently, chemical vapor deposition (CVD) of graphene and few-layer graphene using hydrocarbons on metal substrates such as Ni and Cu has shown to be a promising technique2-5. It has been proposed in recent publications that graphene growth o

  36. Marta Lewicka, Reza Pakzad

    This paper concerns the elastic structures which exhibit non-zero strain at free equilibria. Many growing tissues (leaves, flowers or marine invertebrates) attain complicated configurations during their free growth. Our study departs from the 3d incompatible elasticity theory, conjectured to explain the mechanism for the spontaneous formation of non-Euclidea

  37. D. Vader, A. Kabla, D. Weitz, L. Mahadevan

    Collagen is the most abundant extracellular-network-forming protein in animal biology and is important in both natural and artificial tissues, where it serves as a material of great mechanical versatility. This versatility arises from its almost unique ability to remodel under applied loads into anisotropic and inhomogeneous structures. To explore the origin

  38. Y. S. Kim

    As in the case of the hydrogen atom, bound-state wave functions are needed to generate hadronic spectra. For this purpose, in 1971, Feynman and his students wrote down a Lorentz-invariant harmonic oscillator equation. This differential equation has one set of solutions satisfying the Lorentz-covariant boundary condition. This covariant set generates Lorentz-

  39. Hazer Inaltekin, Robert Jarrow, Mehmet Saglam, Yildiray Yildirim

    In this article, we develop a model for the evolution of real estate prices. A wide range of inputs, including stochastic interest rates and changing demands for the asset, are considered. Maximizing their expected utility, home owners make optimal sale decisions given these changing market conditions. Using these optimal sale decisions, we simulate the impl

  40. Elizabeth E. Jenkins

    The 1/N_c expansion of QCD with N_c=3 has been successful in explaining a wide variety of QCD phenomenology. Here I focus on the contracted spin-flavor symmetry of baryons in the large-N_c limit and deviations from spin-flavor symmetry due to corrections suppressed by powers of 1/N_c. Baryon masses provide an important example of the 1/N_c expansion, and suc

  41. D. Basu

    The redshifts of the gamma ray burst (GRB) GRB 011211 has been determined as 2.14 from several absorption lines seen in the spectrum of its optical afterglow. The spectrum of its X-ray afterglow exhibited several emission lines,and their identification led to a mean redshift 1.862. A supernova model has been proposed based on the redshift of the GRB as 2.141

  42. M. Maturi, C. Angrick, M. Bartelmann, F. Pace

    We develop and apply an analytic method to predict peak counts in weak-lensing surveys. It is based on the theory of Gaussian random fields and suitable to quantify the level of spurious detections caused by chance projections of large-scale structures as well as the shape and shot noise contributed by the background galaxies. We compare our method to peak c

  43. Harald Wunderlich, Martin B. Plenio

    Many experiments in quantum information aim at creating graph states. Quantifying the purity of an experimentally achieved graph state could in principle be accomplished using full-state tomography. This method requires a number of measurement settings growing exponentially with the number of constituents involved. Thus, full-state tomography becomes experim

  44. Simon F. Ross, Omid Saremi

    We discuss the calculation of the field theory stress tensor from the dual geometry for two recent proposals for gravity duals of non-relativistic conformal field theories. The first of these has a Schrodinger symmetry including Galilean boosts, while the second has just an anisotropic scale invariance (the Lifshitz case). For the Lifshitz case, we construct

  45. Damir Becirevic, Benjamin Haas, Emi Kou

    We point out at the peculiarity of B --> mu nu decay, namely the enhancement of the soft photon events which originate from the structure dependent part of the B --> mu nu gamma amplitude. This may be a dominant source of systematic uncertainty and compromise the projected experimental uncertainty on Gamma(B --> mu nu). We show that the effect of these soft

  46. Gero Friesecke, Oliver Junge, Péter Koltai

    We propose a new approach to the transfer operator based analysis of the conformation dynamics of molecules. It is based on a statistical independence ansatz for the eigenfunctions of the operator related to a partitioning into subsystems. Numerical tests performed on small systems show excellent qualitative agreement between mean field and exact model, at g

  47. Pierre Kervella, Tijl Verhoelst, Stephen T. Ridgway, Guy Perrin

    Context: Betelgeuse is one the largest stars in the sky in terms of angular diameter. Structures on the stellar photosphere have been detected in the visible and near-infrared as well as a compact molecular environment called the MOLsphere. Mid-infrared observations have revealed the nature of some of the molecules in the MOLsphere, some being the precursor

  48. O. V. Manyuhina, A. Fasolino, M. I. Katsnelson

    We show that the stacking of flat aromatic molecules on a curved surface results in topological defects. We consider, as an example, spherical vesicles, self-assembled from molecules with 5- and 6-thiophene cores. We predict that the symmetry of the molecules influences the number of topological defects and the resulting equilibrium shape.

  49. C. Maieron, J. E. Amaro, M. B. Barbaro, J. A. Caballero

    The present study is focused on the superscaling behavior of electron-nucleus cross sections in the region lying above the quasielastic peak, especially the region dominated by electroexcitation of the Delta. Non-quasielastic cross sections are obtained from all available high-quality data for Carbon 12 by subtracting effective quasielastic cross sections ba

  50. Paola Bonizzoni, Gianluca Della Vedova, Riccardo Dondi

    The Consensus Clustering problem has been introduced as an effective way to analyze the results of different microarray experiments. The problem consists of looking for a partition that best summarizes a set of input partitions (each corresponding to a different microarray experiment) under a simple and intuitive cost function. The problem admits polynomial

  51. Michael E. Palmer, Daniel B. Miller

    We successfully evolved a neural network controller that produces dynamic walking in a simulated bipedal robot with compliant actuators, a difficult control problem. The evolutionary evaluation uses a detailed software simulation of a physical robot. We describe: 1) a novel theoretical method to encourage populations to evolve "around" local optima,

  52. Vasily E. Tarasov

    The dielectric susceptibility of most materials follows a fractional power-law frequency dependence that is called the "universal" response. We prove that in the time domain this dependence gives differential equations with derivatives and integrals of noninteger order. We obtain equations that describe "universal" Curie-von Schweidler and Ga

  53. C. T. J. Dodson

    The information geometry of the 2-manifold of gamma probability density functions provides a framework in which pseudorandom number generators may be evaluated using a neighbourhood of the curve of exponential density functions. The process is illustrated using the pseudorandom number generator in Mathematica. This methodology may be useful to add to the cur

  54. R. R. Gontsov

    We study movable singularities of Garnier systems using the connection of the latter with Schlesinger isomonodromic deformations of Fuchsian systems

  55. J. -P. Lenain

    In the recent years, the new generation of Imaging Atmospheric Cerenkov Telescopes successfully detected very high energy (VHE; E>100 GeV) gamma-ray emission from a growing number of Active Galactic Nuclei (AGNs), mainly belonging to the blazar class. Among these recent results, we will mainly focus in this work on two recent discoveries made with the H.E.S.

  56. Antonio De Felice, Shinji Tsujikawa

    We discuss solar system constraints on f(G) gravity models, where f is a function of the Gauss-Bonnet term G. We focus on cosmologically viable f(G) models that can be responsible for late-time cosmic acceleration. These models generally give rise to corrections of the form epsilon*(r/rs)^p to the vacuum Schwarzschild solution, where epsilon = H^2 rs^2 << 1,

  57. Astrid Eichhorn, Holger Gies, Michael M. Scherer

    We consider the asymptotic-safety scenario for quantum gravity which constructs a non-perturbatively renormalisable quantum gravity theory with the help of the functional renormalisation group. We verify the existence of a non-Gaussian fixed point and include a running curvature-ghost coupling as a first step towards the flow of the ghost sector of the theor

  58. K. Bastiaensen, P. Cauwels, D. Sornette, R. Woodard

    Amid the current financial crisis, there has been one equity index beating all others: the Shanghai Composite. Our analysis of this main Chinese equity index shows clear signatures of a bubble build up and we go on to predict its most likely crash date: July 17-27, 2009 (20%/80% quantile confidence interval).

  59. Andrey Pepelyshev

    Designs of experiments for multivariate case are reviewed. Fast algorithm of construction of good Latin hypercube designs is developed.

  60. Antonio Degasperis, Sara Lombardo

    The Darboux Dressing Transformations developed in our previous paper (Multicomponent integrable wave equations I. Darboux-Dressing Transformation, J. Phys. A: Math. Theor. 40, 961-977, 2007) are here applied to construct soliton solutions for a class of boomeronic type equations. The vacuum (i.e. vanishing) solution and the generic plane wave solution are bo

  61. Alex Degtyarev

    We compute the fundamental groups of all irreducible plane sextics constituting classical Zariski pairs

  62. Sheng-Gwo Chen, Mei-Hsiu Chi, Jyh-Yang Wu

    In this note we shall introduce a simple, effective numerical method for solving partial differential equations for scalar and vector-valued data defined on surfaces. Even though we shall follow the traditional way to approximate the regular surfaces under consideration by triangular meshes, the key idea of our algorithm is to develop an intrinsic and unifie

  63. Hal Daumé

    We describe an approach to domain adaptation that is appropriate exactly in the case when one has enough ``target&#39;&#39; data to do slightly better than just using only ``source&#39;&#39; data. Our approach is incredibly simple, easy to implement as a preprocessing step (10 lines of Perl!) and outperforms state-of-the-art approaches on a range of datasets

  64. Hal Daumé

    We present BayeSum (for ``Bayesian summarization&#39;&#39;), a model for sentence extraction in query-focused summarization. BayeSum leverages the common case in which multiple documents are relevant to a single query. Using these documents as reinforcement for query terms, BayeSum is not afflicted by the paucity of information in short queries. We show that

  65. Hal Daumé

    Dirichlet process (DP) mixture models provide a flexible Bayesian framework for density estimation. Unfortunately, their flexibility comes at a cost: inference in DP mixture models is computationally expensive, even when conjugate distributions are used. In the common case when one seeks only a maximum a posteriori assignment of data points to clusters, we s

  66. A. Caproni, H. Monteiro, Z. Abraham

    Evidence of jet precession in many galactic and extragalactic sources has been reported in the literature. Much of this evidence is based on studies of the kinematics of the jet knots, which depends on the correct identification of the components to determine their respective proper motions and position angles on the plane of the sky. Identification problems

  67. O. G. Udalov, A. A. Fraerman

    The phenomenological theory for &#34;topological&#34; Hall effect (THE) is proposed. The theory can be used for qualitative analysis of THE in the medium with arbitrary magnetization distribution. In the paper the cylindrical particle with &#34;vortex&#34; magnetization is considered. The hysteresis loop of THE is qualitatively different comparing to abnorma

  68. Khanh-Dang Nguyen Thu Lam, Jorge Kurchan, Dov Levine

    Given a chaotic dynamical system and a time interval in which some quantity takes an unusually large average value, what can we say of the trajectory that yields this deviation? As an example, we study the trajectories of the archetypical chaotic system, the baker&#39;s map. We show that, out of all irregular trajectories, a large-deviation requirement selec

  69. Gabor Elek, Gabor Lippner

    Nguyen and Onak constructed the first constant-time algorithm for the approximation of the size of the maximum matching in bounded degree graphs. The Borel oracle machinery is a tool that can be used to convert some statements in Borel graph theory to theorems in the field of constant-time algorithms. In this paper we illustrate the power of this tool to pro

  70. Gurpreet Singh, S. L. Gupta, R. Prasad, S. Auluck

    The effect of doping spinel LiMn2O4 with chromium and magnesium has been studied using the first-principles spin density functional theory within GGA (generalized gradient approximation) and GGA+U. We find that GGA and GGA+U give different ground states for pristine LiMn2O4 and same ground state for doped systems. For LiMn2O4 the body centered tetragonal pha

  71. A. Tarasov, S. Hugger, Hengyi Xu, M. Cerchez

    Ballistic quantum wires are exposed to longitudinal profiles of perpendicular magnetic fields composed of a spike (magnetic barrier) and a homogeneous part. An asymmetric magnetoconductance peak as a function of the homogeneous magnetic field is found, comprising quantized conductance steps in the interval where the homogeneous magnetic field and the magneti

  72. Y. M. Xiong, P. W. Adams, G. Catelani

    We show that the pairing resonance in the Pauli-limited normal state of ultra-thin superconducting Al films provides a spin-resolved probe of conduction electron polarization in thin magnetic films. A superconductor-insulator-ferromagnet tunneling junction is used to measure the density of states in supercritical parallel magnetic fields that are well beyond

  73. T. Rajasekharan, V. Seshubai

    The parameters Phi and N of Miedema are quoted precise to the second decimal place and are considered very accurate after adjustment in their values to correctly predict the signs of the heats of formation of more than 500 metallic binary systems. In this paper, we argue that Phi is proportional to the electronegativity (Chi) of metallic elements and that N^

  74. Renat Zhdanov

    We suggest the method for group classification of evolution equations admitting nonlocal symmetries which are associated with a given evolution equation possessing nontrivial Lie symmetry. We apply this method to second-order evolution equations in one spatial variable invariant under Lie algebras of the dimension up to three. As a result, we construct the b

  75. Emilio N. M. Cirillo, Francesca R. Nardi

    We consider the problem of metastability for a stochastic dynamics with a parallel updating rule with single spin rates equal to those of the heat bath for the Ising nearest neighbors interaction. We study the exit from the metastable phase, we describe the typical exit path and evaluate the exit time. We prove that the phenomenology of metastability is diff

  76. Florentin Millour

    What is long-baseline optical/IR stellar interferometry? A few years ago, many astronomers might not have been able to answer that question properly. This is today hopefully not the case anymore, because mainstream facilities, such as the VLTI, the Keck-I or the CHARA array, offer now this delicate technique to an astronomer who wants to observe his favourit

  77. Patricia Reynaud-Bouret, Vincent Rivoirard, Christine Tuleau-Malot

    This paper deals with the classical problem of density estimation on the real line. Most of the existing papers devoted to minimax properties assume that the support of the underlying density is bounded and known. But this assumption may be very difficult to handle in practice. In this work, we show that, exactly as a curse of dimensionality exists when the

  78. Stefan Felsner, Mareike Massow

    The linear extension diameter of a finite poset P is the maximum distance between a pair of linear extensions of P, where the distance between two linear extensions is the number of pairs of elements of P appearing in different orders in the two linear extensions. We prove a formula for the linear extension diameter of the Boolean Lattice and characterize th

  79. J. Kiukas, A. Ruschhaupt, R. F. Werner

    We consider the time delay of massive, non-relativistic, one-dimensional particles due to a tunneling potential. In this setting the well-known Hartman effect asserts that often the sub-ensemble of particles going through the tunnel seems to cross the tunnel region instantaneously. An obstacle to the utilization of this effect for getting faster signals is t

  80. Ales Drapal, Carlo Hamalainen, Viteslav Kala

    Let $T = (T^{\textstyle \ast}, T^{\scriptscriptstyle \triangle})$ be a spherical latin bitrade. With each $a=(a_1,a_2,a_3)\in T^{\textstyle \ast}$ associate a set of linear equations $\eq(T,a)$ of the form $b_1+b_2=b_3$, where $b = (b_1,b_2,b_3)$ runs through $T^{\textstyle \ast} \setminus \{a\}$. Assume $a_1 = 0 = a_2$ and $a_3 = 1$. Then $\eq(T,a)$ has in

  81. Alexandre Soro, Jerome Lacan

    This paper presents a new construction of Maximum-Distance Separable (MDS) Reed-Solomon erasure codes based on Fermat Number Transform (FNT). Thanks to FNT, these codes support practical coding and decoding algorithms with complexity O(n log n), where n is the number of symbols of a codeword. An open-source implementation shows that the encoding speed can re

  82. Anne-Laure Dalibard, Laure Saint-Raymond

    This article is concerned with an oceanographic model describing the asymptotic behaviour of a rapidly rotating and incompressible fluid with an inhomogeneous rotation vector; the motion takes place in a thin layer. We first exhibit a stationary solution of the system which consists of an interior part and a boundary layer part. The spatial variations of the

  83. S. Kanmani

    Quantum mechanics of composite systems, gives rise to certain special states called entangled states. A physical system, that is in an entangled state displays an intricate correlation between its subsystems. There are also some composite quantum states (classically correlated states or separable states) that are not entangled. It is generally claimed, often

  84. Ronin Wu, David W. Hogg, John Moustakas

    We present optical and mid-infrared photometry of a statistically complete sample of 29 very faint dwarf galaxies (M_r > -15 mag) selected from the SDSS spectroscopic sample and observed in the mid-infrared with Spitzer IRAC. This sample contains nearby (redshift z<0.005) galaxies three magnitudes fainter than previously studied samples. We compare our sampl

  85. H. Zhang, D. Y. Tang, X. Wu, L. M. Zhao

    We report on the generation of multi-wavelength dissipative soliton (DS) in an all normal dispersion fiber laser passively mode-locked with a semiconductor saturable absorber mirror (SESAM). We show that depending on the strength of the cavity birefringence, stable single-, dual- and triple-wavelength DSs can be formed in the laser. The multi-wavelength soli

  86. Luca Merlo

    The neutrino oscillation data are well explained by the tri-bimaximal pattern. Recently it has been shown that also the bimaximal pattern could be a very good starting point in order to describe the lepton mixing. In this paper I review both the flavour structures and then I present an explicit example.

  87. Evgeny Epelbaum, Ulf-G. Meißner

    These are the proceedings of the symposium on ``Frontiers in Nuclear Physics&#39;&#39; held at the Physikzentrum Bad Honnef from June 18 to 20, 2009. The workshop concentrated on recent advances in the understanding of the nuclear forces, few-nucleon systems and related topics. Included are a short contribution per talk.

  88. S. Grauwin, F. Goffette-Nagot, P. Jensen

    In his 1971&#39;s Dynamic Models of Segregation paper, the economist Thomas C. Schelling showed that a small preference for one&#39;s neighbors to be of the same color could lead to total segregation, even if total segregation does not correspond to individual preferences and to a residential configuration maximizing the collective utility. The present work

  89. The BABAR Collaboration, B. Aubert

    We present measurements of the branching fraction B and the longitudinal polarization fraction fL for B0 -> a1(1260)+ a1(1260)- decays, with a1(1260)+/- -> π- π+ π+/-. The data sample, collected with the detector BaBar at the SLAC National Accelerator Laboratory, represents 465 10^6 produced BBbar pairs. We measure B(B0 -> a1(1260)+ a1(1260)-) x [B(a1(1260)+

  90. S. Ayik, O. Yilmaz, N. Er, A. Gokalp

    Spinodal instabilities and early growth of baryon density fluctuations in symmetric nuclear matter are investigated in the basis of stochastic extension of relativistic mean-field approach in the semi-classical approximation. Calculations are compared with the results of non-relativistic calculations based on Skyrme-type effective interactions under similar

  91. Masashi Tachiki, Tomio Koyama, Shouta Fukuya

    We reply to the comment [arXiv:0903.5110] on our paper &#34;Mechanism of Terahertz Electromagnetic Emission from Intrinsic Josephson Junctions&#34; [arXiv:0810.5268].

  92. Liu Xue-Wen, Wu Xue-Feng, Lu Tan

    GRB 080913, with a spectroscopically determined redshift of z=6.7, was the record holder of the remotest stellar object before the discovery of the recent gamma-ray burst GRB 090423, whose redshift is about 8.2. The gradually accumulated high redshift GRB sample has shed light on the origin and physics of GRBs during the cosmic re-ionization epoch. We here p

  93. J. Robert Buchler

    We review the current state of Cepheid modeling and discuss its dominant deficiency, namely the use of time dependent mixing length. Notwithstanding, Cepheid modeling has achieved some excellent successes, and we mention some of the most recent ones. Discrepancies between observations and modeling appear not so much in the gross properties of single mode Cep

  94. P. Ventura, V. Caloi, F. D&#39;Antona, J. Ferguson

    Among the newly discovered features of multiple stellar populations in Globular Clusters, the cluster NGC 1851 harbours a double subgiant branch, that can be explained in terms of two stellar generations, only slightly differing in age, the younger one having an increased total C+N+O abundance. Thanks to this difference in the chemistry, a fit can be made to

  95. A M Cooper-Sarkar

    New ZEUS data are added into the NLO QCD analysis of the ZEUS-JETS PDF fit. The addition of high-$Q^2$ NC and CC $e^-p$ inclusive cross-section data improves the determination of the $u$-valence quark at high $x$. The addition of high-$Q^2$ CC $e^+p$ inclusive cross-section data improves the determination of the $d$-valence quark at high $x$. The addition of

  96. Lina Guo, Zhiqiang Wang

    By means of a direct and constructive method based on the theory of semiglobal $C^2$ solution, the local exact boundary observability is shown for nonautonomous 1-D quasilinear wave equations. The essential difference between nonautonomous wave equations and autonomous ones is also revealed.

  97. D. G. Middleton, J. R. M. Annand, C. Barbieri, C. Giusti

    After recent improvements to the Pavia model of two-nucleon knockout from $^{16}$O with electromagnetic probes the calculated cross sections are compared to experimental data from such reactions. Comparison with data from a measurement of the $^{16}$O(e,e$&#39;$pn) reaction show much better agreement between experiment and theory than was previously observed

  98. Michael Devin, Tibra Ali, Gerald Cleaver, Anzhong Wang

    In this paper, we study the implementation of brane worlds in type II string theory. Starting with the NS/NS sector of type II string, we first compactify the $(D+d_{+} + d_{-})$-dimensional spacetime, and reduce the corresponding action to a D-dimensional effective action, where the topologies of $M_{d_{+}}$ and $M_{d_{-}}$ are arbitrary. We further compact

  99. R. T. Faizullin, I. G. Khnykin, V. I. Dylkeyt

    The one of the most interesting problem of discrete mathematics is the SAT (satisfiability) problem. Good way in SAT solver developing is to transform the SAT problem to the problem of continuous search of global minimums of the functional associated with the CNF. This article proves the special construction of the functional and offers to solve the system o

  100. Marcus S. Cohen

    We start with the spinfluid: a nearly-homogeneous, 8-spinor medium, with small local eddies and twists. As it expends, these seed a raft of intersecting codimension-J singularities: a spinfoam. As this expands, the energy trapped in each (4-J) brane varies as the Jth power of the scale factor. Summing on J=(0,1,2,3,4) creates a quartic dilation potential wit