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January 2010 arXiv papers — page 46

Showing 4,5014,600 of 5,448 papers

  1. N. B. Kopnin, E. B. Sonin

    The problem of supercurrent in superconducting graphene is revisited and the supercurrent is calculated within the mean-field model employing the two-component wave functions on a honeycomb lattice with pairing between different valleys in the Brillouin zone. We show that the supercurrent within the linear approximation in the order-parameter-phase gradient

  2. T. Mertelj, P. Kusar, V. V. Kabanov, L. Stojchevska

    We investigate the quasiparticle relaxation and low-energy electronic structure in undoped SmFeAsO and near-optimally doped SmFeAsO_{0.8}F_{0.2} single crystals - exhibiting spin-density wave (SDW) ordering and superconductivity respectively - using pump-probe femtosecond spectroscopy. In the undoped single crystals a single relaxation process is observed, s

  3. Serena Fagnocchi, Stefano Finazzi, Stefano Liberati, Marton Kormos

    In this paper we propose to apply the analogy between gravity and condensed matter physics to relativistic Bose-Einstein condensates (RBECs), i.e. condensates composed by relativistic constituents. While such systems are not yet a subject of experimental realization, they do provide us with a very rich analogue model of gravity, characterized by several nove

  4. Silvia Garbari, George Lake, Justin I. Read

    We examine systematic problems in determining the local matter density from the vertical motion of stars, i.e. the 'Oort limit'. Using collisionless simulations and a Monte Carlo Markov Chain technique, we determine the data quality required to detect local dark matter at its expected density. We find that systematic errors are more important than ob

  5. Boubaker Smii

    In this paper we consider a stochastic partial differential equation defined on a Lattice $L_δ$ with coefficients of non-linearity with degree $p$. An analytic solution in the sense of formal power series is given. The obtained series can be re-expressed in terms of rooted trees with two types of leaves. Under the use of the so-called Cole-Hopf transformatio

  6. Metin Gurses

    Killing vector fields in three dimensions play important role in the construction of the related spacetime geometry. In this work we show that when a three dimensional geometry admits a Killing vector field then the Ricci tensor of the geometry is determined in terms of the Killing vector field and its scalars. In this way we can generate all products and co

  7. Ali Hosseiny, Shahin Rouhani

    We show how logarithmic terms may arise in the correlators of fields which belong to the representation of the Schrodinger-Virasoro algebra (SV) or the affine Galilean Conformal Algebra (GCA). We show that in GCA, only scaling operator can have a Jordanian form and rapidity can not. We observe that in both algebras logarithmic dependence appears along the ti

  8. Wenxian Zhang, Bo Sun, M. S. Chapman, L. You

    We propose to localize spin mixing dynamics in a spin-1 Bose-Einstein condensate by a temporal modulation of spin exchange interaction, which is tunable with optical Feshbach resonance. Adopting techniques from coherent control, we demonstrate the localization/freezing of spin mixing dynamics, and the suppression of the intrinsic dynamic instability and spon

  9. S. Salimi, R. Radgohar

    In this paper, we study mixing and large decoherence in continuous-time quantum walks on one dimensional regular networks, which are constructed by connecting each node to its $2l$ nearest neighbors($l$ on either side). In our investigation, the nodes of network are represented by a set of identical tunnel-coupled quantum dots in which decoherence is induced

  10. Yucai Su, R. B. Zhang

    A Jantzen type filtration for generalised Varma modules of Lie superalgebras is introduced. In the case of type I Lie superalgebras, it is shown that the generalised Jantzen filtration for any Kac module is the unique Loewy filtration, and the decomposition numbers of the layers of the filtration are determined by the coefficients of inverse Kazhdan-Lusztig

  11. Alexey Kuznetsov

    We study the Wiener--Hopf factorization and the distribution of extrema for general stable processes. By connecting the Wiener--Hopf factors with a certain elliptic-like function we are able to obtain many explicit and general results, such as infinite series representations and asymptotic expansions for the density of supremum, explicit expressions for the

  12. Jascha Sohl-Dickstein, Ching Ming Wang, Bruno A. Olshausen

    We present several theoretical contributions which allow Lie groups to be fit to high dimensional datasets. Transformation operators are represented in their eigen-basis, reducing the computational complexity of parameter estimation to that of training a linear transformation model. A transformation specific "blurring" operator is introduced that all

  13. Wei Chen, Oleg P. Sushkov, Takami Tohyama

    We show that lightly doped YBa$_2$Cu$_3$O$_{6+y}$ has multiple holon pockets with different areas, which lead to multiple frequencies of magnetic quantum oscillations. Using neutron scattering data on incommensurate spin ordering we determine these areas, which yields frequencies in good agreement with experiments. Divergence of the effective mass observed i

  14. A. Bhattacharyay

    We investigate an exactly solvable model for directional transport in 1D. The structured system, which has strong elastic interactions in its parts, explicitly demonstrates the role of volume exclusion in producing directional transport. We capture the complementary role of the elasticity and volume exclusion as the basic ingredient for showing up of broken

  15. Munetaka Sasaki

    A new formulation of the stochastic potential switching algorithm is presented. This reformulation naturally leads us to a generalized Fourtuin-Kasteleyn representation of the partition function Z. A formula for internal energy E and that of heat capacity C are derived from derivatives of the partition function. We also derive a formula for the exchange prob

  16. Bartolomeu F. Uchoa-Filho, Roberto W. Nobrega

    In this paper, we consider noncoherent random linear coding networks (RLCNs) as a discrete memoryless channel (DMC) whose input and output alphabets consist of subspaces. This contrasts with previous channel models in the literature which assume matrices as the channel input and output. No particular assumptions are made on the network topology or the transf

  17. Alexander Borichev, Don Hadwin, Hassan Yousefi

    We prove that if T is an operator on an infinite-dimensional Hilbert space whose spectrum and essential spectrum are both connected and whose Fredholm index is only 0 or 1, then the only nontrivial norm-stable invariant subspaces of T are the finite-dimensional ones. We also characterize norm-stable invariant subspaces of any weighted unilateral shift operat

  18. Xiang Zhou, Zhibin Lin, Chenwei Jiang, Meng Gao

    For molecules and materials responding to femtosecond-scale optical laser pulses, we predict maximum relative excitation of a Raman-active vibrational mode with period T when the pulse has an FWHM duration of 0.42 T. This result follows from a general analytical model, and is precisely confirmed by detailed density-functional-based dynamical simulations for

  19. Wm. G. Hoover, Carol G. Hoover

    Guided by molecular dynamics simulations, we generalize the Navier-Stokes-Fourier constitutive equations and the continuum motion equations to include both transverse and longitudinal temperatures. To do so we partition the contributions of the heat transfer, the work done, and the heat flux vector between the longitudinal and transverse temperatures. With s

  20. Daniel Gervini

    This article introduces trimmed estimators for the mean and covariance function of general functional data. The estimators are based on a new measure of outlyingness or data depth that is well defined on any metric space, although this paper focuses on Euclidean spaces. We compute the breakdown point of the estimators and show that the optimal breakdown poin

  21. Medini Padmanabhan, T. Gokmen, M. Shayegan

    We study a two-dimensional electron system where the electrons occupy two conduction band valleys with anisotropic Fermi contours and strain-tunable occupation. We observe persistent quantum Hall states at filling factors $ν= 1/3$ and 5/3 even at zero strain when the two valleys are degenerate. This is reminiscent of the quantum Hall ferromagnet formed at $ν

  22. Gabriel Abreu, Matt Visser

    The quantum inequalities, and the closely related quantum interest conjecture, impose restrictions on the distribution of the energy density measured by any time-like observer, potentially preventing the existence of exotic phenomena such as Alcubierre warp-drives or traversable wormholes. It has already been proved that both assertions can be reduced to sta

  23. S. Costamagna, O. Hernandez, A. Dobry

    We study the effects of the structural corrugation or rippling on the electronic properties of undoped armchair graphene nanoribbons (AGNR). First, reanalyzing the single corrugated graphene layer we find that the two inequivalent Dirac points (DP), move away one from the other. Otherwise, the Fermi velocity decrease by increasing rippling. Regarding the AGN

  24. David S. De Young

    Radio AGN feedback is often assumed to work, but detailed physical models of this process are not well developed. This paper examines a possible path for radio AGN feedback to heat the gas in and around galaxies and perhaps suppress star formation. Nearby radio AGN are almost all FR-I radio galaxies, and it is argued that such outflows become decelerated and

  25. Kevin Apps, Kelsey I. Clubb, Debra A. Fischer, Eric Gaidos

    Doppler observations from Keck Observatory reveal the presence of a planet with Msini of 2.1 Mjup orbiting the M3V star HIP79431. This is the sixth giant planet to be detected in Doppler surveys of M dwarfs and it is one of the most massive planets discovered around an M dwarf star. The planet has an orbital period of 111.7 days and an orbital eccentricity o

  26. John Horton

    Online labor markets give people in poor countries direct access to buyers in rich countries. Economic theory and empirical evidence strongly suggest that this kind of access improves human welfare. However, critics claim that abuses are endemic in these markets and that employers exploit unprotected, vulnerable workers. I investigate part of this claim usin

  27. Jie L. Xiong, Mei Song Tong, Phillip Atkins, Weng Cho Chew

    In this paper, we generalized the surface integral equation method for the evaluation of Casimir force in arbitrary three-dimensional geometries. Similar to the two-dimensional case, the evaluation of the mean Maxwell stress tensor is cast into solving a series of three-dimensional scattering problems. The formulation and solution of the three-dimensional sc

  28. Ard A. Louis

    I briefly review some concepts related to coarse-graining methods for the dynamics of soft matter systems and argue that such schemes will almost always need to telescope down the physical hierarchy of time-scales to a more compressed, but more computationally manageable, separation.

  29. Andrea Dieball, Knox S. Long, Christian Knigge, Grace S. Thomson

    Using the ACS on HST, we have surveyed the FUV and NUV populations in the core region of M80. The CMD reveals large numbers of blue and extreme horizontal branch stars and blue stragglers, as well as approx. 60 objects lying in the region of the CMD where accreting and detached white dwarf binaries are expected. Overall, the blue straggler stars are the most

  30. Paul D. Lasky, Krzysztof Bolejko

    Inhomogeneous cosmological models have had significant success in explaining cosmological observations without the need for dark energy. Generally, these models imply inhomogeneous matter distributions alter the observable relations that are taken for granted when assuming the Universe evolves according to the standard Friedmann equations. Moreover, it has r

  31. A. Gal-Yam, P. Mazzali, E. O. Ofek, P. E. Nugent

    Stars with initial masses 10 M_{solar} < M_{initial} < 100 M_{solar} fuse progressively heavier elements in their centres, up to inert iron. The core then gravitationally collapses to a neutron star or a black hole, leading to an explosion -- an iron-core-collapse supernova (SN). In contrast, extremely massive stars (M_{initial} > 140 M_{solar}), if such exi

  32. X. Artru, C. Ray

    Travelling wave in a helical wave guide is considered for electron acceleration. A first determination of the travelling wave modes using a partial wave expansion (PWE) and a point matching method is presented. It gives a rapid solution for moderate deformation of the guide relative to a straight cylinder. Strong deformations will give higher accelerating gr

  33. Jerome Dubail, Jesper Lykke Jacobsen, Hubert Saleur

    A good understanding of conformal field theory (CFT) at c=0 is vital to the physics of disordered systems, as well as geometrical problems such as polymers and percolation. Steady progress has shown that these CFTs should be logarithmic, with indecomposable operator product expansions, and indecomposable representations of the Virasoro algebra. In one of the

  34. A. M. Shuvaev, V. D. Travkin, V. Yu. Ivanov, A. A. Mukhin

    Terahertz electromagnetic excitations in the multiferroic TbMnO3 at the field-induced magnetic transition are investigated for different orientations of the magnetic cycloid. In addition to the electromagnon along the a-axis, the detailed polarization analysis of the experimental spectra suggests the existence of an electro-active excitation for ac electric

  35. S. V. Borisenko, V. B. Zabolotnyy, D. V. Evtushinsky, T. K. Kim

    The particular shape of the Fermi surface can give rise to a number of collective quantum phenomena in solids, such as density wave orderings or even superconductivity. In many new iron superconductors this shape, the &#39;nested&#39; Fermi surface, is indeed observed, but its role in the formation of spin-density waves or superconductivity is not clear. We

  36. Matthew Daws

    A dual Banach algebra is a Banach algebra which is a dual space, with the multiplication being separately weak$^*$-continuous. We show that given a unital dual Banach algebra $\mc A$, we can find a reflexive Banach space $E$, and an isometric, weak$^*$-weak$^*$-continuous homomorphism $π:\mc A\to\mc B(E)$ such that $π(\mc A)$ equals its own bicommutant.

  37. M. Merkli, G. P. Berman, F. Borgonovi, K. Gebresellasie

    We analyze rigorously the dynamics of the entanglement between two qubits which interact only through collective and local environments. Our approach is based on the resonance perturbation theory which assumes a small interaction between the qubits and the environments. The main advantage of our approach is that the expressions for (i) characteristic time-sc

  38. Loet Leydesdorff

    Mutual information among three or more dimensions (mu-star = - Q) has been considered as interaction information. However, Krippendorff (2009a, 2009b) has shown that this measure cannot be interpreted as a unique property of the interactions and has proposed an alternative measure of interaction information based on iterative approximation of maximum entropi

  39. S. I. Denisov, H. Kantz

    We present analytical results for the biased diffusion of particles moving under a constant force in a randomly layered medium. The influence of this medium on the particle dynamics is modeled by a piecewise constant random force. The long-time behavior of the particle position is studied in the frame of a continuous-time random walk on a semi-infinite one-d

  40. S. A. Moiseev, F. F. Gubaidullin, S. N. Andrianov

    First solid state quantum computer was built using transmons (cooper pair boxes). The operation of the computer is limited because of using a number of the rigit cooper boxes working with fixed frequency at temperatures of superconducting material. Here, we propose a novel architecture of quantum computer based on a flexible wire circuit of many coupled quan

  41. W A Bryan, C R Calvert, R B King, G R A J Nemeth

    A quasi-classical model (QCM) of molecular dynamics in intense femtosecond laser fields has been developed, and applied to a study of the effect of an ultrashort `control&#39; pulse on the vibrational motion of a deuterium molecular ion in its ground electronic state. A nonadiabatic treatment accounts for the initial ionization-induced vibrational population

  42. Robert D. Grober

    This paper summarizes two previously published technical papers describing what can be learned from measuring the motion of the golf club using two accelerometers. The sensors are mounted at different points along the shaft of the golf club, both sensitive to acceleration along the axis of the shaft. Two distinct signals are resolved. The first signal scales

  43. Fabio Bagarello

    In a recent paper, Trifonov suggested a possible explicit model of a PT-symmetric system based on a modification of the canonical commutation relation. Although being rather intriguing, in his treatment many mathematical aspects of the model have just been neglected, making most of the results of that paper purely formal. For this reason we are re-considerin

  44. Shai Covo

    Let {X_{t_1,t_2}: t_1,t_2 >= 0} be a two-parameter Lévy process on R^d. We study basic properties of the one-parameter process {X_{x(t),y(t)}: t \in T} where x and y are, respectively, nondecreasing and nonincreasing nonnegative continuous functions on the interval T. We focus on and characterize the case where the process has stationary increments.

  45. R. S. Longacre

    In an earlier paper we developed a Parton Bubble Model (PBM) for RHIC, high-energy heavy-ion collisions. PBM was based on a substructure of a ring of localized bubbles (gluonic hot spots) which initially contain 3-4 partons composed of almost entirely gluons. The bubbles emitted correlated particles at kinetic freezeout, leading to a lumpy fireball surface.

  46. F. J. Gallego, B. P. Purnaprajna

    In this article we study the bicanonical map $ϕ_2$ of quadruple Galois canonical covers X of surfaces of minimal degree. We show that $ϕ_2$ has diverse behavior and exhibit most of the complexities that are possible for a bicanonical map of surfaces of general type, depending on the type of X. There are cases in which $ϕ_2$ is an embedding, and if so happens

  47. Helmut Eschrig, Alexander Lankau, Klaus Koepernik

    The layered structure of the iron based superconductors gives rise to a more or less pronounced two-dimensionality of their electronic structure, most pronounced in LaOFeAs. A consequence are distinct surface states to be expected to influence any surface sensitive experimental probe. In this work a detailed density functional analysis of the cleavage behavi

  48. Nicolas Botbol Marc Dohm

    In this paper we present an algorithm for computing a matrix representation for a surface in P^3 parametrized over a 2-dimensional toric variety T. This algorithm follows the ideas of [Botbol-Dickenstein-Dohm-09] and it was implemented in Macaulay2. We showed in [BDD09] that such a surface can be represented by a matrix of linear syzygies if the base points

  49. L. A. Openov, A. I. Podlivaev

    The process of hydrogen desorption from graphane (graphene sheet saturated by hydrogen adsorbed from both sides) has been studied using the method of molecular dynamics. The temperature dependences of the time of desorption onset for various hydrogen coverages on graphene are calculated and the corresponding activation energies in the Arrhenius equation are

  50. Markiyan Hirnyk

    We consider the pointwise approximation of a subharmonic function by the logarithm of the modulus of an entire function up to a bounded quantity. In the case of finite order an estimate from below of the planar Lebesgue measure of an exceptional set in such approximation is obtained.

  51. Pye-Ton How, Andre LeClair

    In three spatial dimensions, in the unitary limit of a non-relativistic quantum Bose or Fermi gas, the scattering length diverges. This occurs at a renormalization group fixed point, thus these systems present interesting examples of interacting scale-invariant models with dynamical exponent z=2. We study this problem in two and three spatial dimensions usin

  52. Barbara Pogorelsky

    In this paper we describe the right coideal subalgebras containing all group-like elements of the multiparameter quantum group Uq+(g), where g is a simple Lie algebra of type G2, while the main parameter of quantization q is not a root of 1. If the multiplicative order t of q is finite, t>4, t different from 6, then the same classification remains valid for

  53. Barbara Pogorelsky

    In this paper we describe the right coideal subalgebras containing all group-like elements of the two-parameter quantum groups Uq(g) and uq(g), where g is a simple Lie algebra of type G2. As a consequence, we determine that there are precisely 60 different right coideal subalgebras containing all group-like elements.

  54. Bin Han, Xiaosheng Zhuang

    In this paper, we completely solve the matrix extension problem with symmetry and provide a step-by-step algorithm to construct such a desired matrix $\mathsf{P}_e$ from a given matrix $\mathsf{P}$. Furthermore, using a cascade structure, we obtain a complete representation of any $r\times s$ paraunitary matrix $\mathsf{P}$ having compatible symmetry, which

  55. S. Saesen, F. Carrier, A. Pigulski, C. Aerts

    CONTEXT: Recent progress in the seismic interpretation of field beta Cep stars has resulted in improvements of the physics in the stellar structure and evolution models of massive stars. Further asteroseismic constraints can be obtained from studying ensembles of stars in a young open cluster, which all have similar age, distance and chemical composition. AI

  56. I. Balestra, V. Mainieri, P. Popesso, M. Dickinson

    We present the full data set of the VIMOS spectroscopic campaign of the ESO/GOODS program in the CDFS, which complements the FORS2 ESO/GOODS spectroscopic campaign. The GOODS/VIMOS spectroscopic campaign is structured in two separate surveys using two different VIMOS grisms. The VIMOS Low Resolution Blue (LR-Blue) and Medium Resolution (MR) orange grisms hav

  57. Jean-Marc Kelif, Marceau Coupechoux

    In this paper, we analyse the joint impact of pathloss, shadowing and fast fading on wireless networks. Taking into account the pathloss and the shadowing, we first express the SINR distribution of a mobile located at a given distance from its serving base-station (BS). The moments of this distribution are easily computed, using the Fenton-Wilkinson method,

  58. I. C. Gebeshuber, B. Y. Majlis

    Nature&#39;s materials are complex, multifunctional, hierarchical and responsive and in most instances functionality on the nanoscale is combined with performance on the macroscale. Materials engineers have just started to produce complex nanomaterials. Biomimicry and biomimetics deal with knowledge transfer from nature to technology. Inspired by the &#39;Bi

  59. T. Fragos, M. Tremmel, E. Rantsiou, K. Belczynski

    In black hole X-ray binaries, a misalignment between the spin axis of the black hole and the orbital angular momentum can occur during the supernova explosion that forms the compact object. In this letter we present population synthesis models of Galactic black hole X-ray binaries, and study the probability density function of the misalignment angle, and its

  60. Alexander Luzgarev, Anastasia Stavrova

    Let G be an isotropic reductive algebraic group over a commutative ring R. Assume that the elementary subgroup E(R) of group of points G(R) is correctly defined. Then E(R) is perfect, except for the well-known cases of a split reductive group of type C_2 or G_2.

  61. Eduardo Bauer, Alfredo P. Galeao, Mahir S. Hussein, Francisco Krmpotic

    We compute one- and two-nucleon kinetic-energy spectra and opening-angle distributions for the nonmesonic weak decay of several hypernuclei, and compare our results with some recent data. The decaymics is described by transition potentials of the one-meson-exchange type, and the nuclear structure aspects by two versions of the independent-particle shell mode

  62. Eugen J. Ionascu, Andrew Wilson

    Paul Erdos conjectured that for every n in N, n>1, there exist a, b, c natural numbers, not necessarily distinct, so that 4/n=1/a+1/b+1/c (see \cite{rg}). In this paper we prove an extension of Mordell&#39;s theorem and formulate a conjecture which is stronger than Erdos&#39; conjecture.

  63. S. Moehler, W. Freudling, P. Moller, F. Patat

    ESO&#39;s two FOcal Reducer and low dispersion Spectrographs (FORS) are the primary optical imaging instruments for the VLT. They are not direct-imaging instruments, as there are several optical elements in the light path. In particular, both instruments are attached to a field rotator. Obtaining truly photometric data with such instruments present a signifi

  64. Luca de&#39; Medici, Syed R. Hassan, Massimo Capone

    We show how the general features of the electronic structure of the Fe-based high-Tc superconductors are a natural setting for a selective localization of the conduction electrons to arise. Slave-spin and Dynamical mean-field calculations support this picture and allow for a comparison of the magnetic properties with experiments.

  65. Ard A. Louis

    I briefly review the problem of representability -- a single coarse-grained effective pair potential cannot simultaneously represent all the properties of an underlying more complex system -- as well as a few other subtleties that can arise in interpreting coarse-grained potentials.

  66. F. R. Ferraro, G. Beccari, E. Dalessandro, B. Lanzoni

    Stars in globular clusters are generally believed to have all formed at the same time, early in the Galaxy&#39;s history. &#39;Blue stragglers&#39; are stars massive enough that they should have evolved into white dwarfs long ago. Two possible mechanisms have been proposed for their formation: mass transfer between binary companions and stellar mergers resul

  67. S. Burov, David A. Kessler

    We present a generalized model of a diffusion-reaction system where the reaction occurs only on the boundary. This model reduces to that of Barato and Hinrichsen when the occupancy of the boundary site is restricted to zero or one. In the limit when there is no restriction on the occupancy of the boundary site, the model reduces to an age dependent Galton-Wa

  68. Andrea Carneiro Linhares, Juan-Manuel Torres-Moreno, Peter Peinl, Philippe Michelon

    The efficient use of bandwidth for radio communications becomes more and more crucial when developing new information technologies and their applications. The core issues are addressed by the so-called Frequency Assignment Problems (FAP). Our work investigates static FAP, where an attempt is first made to configure a kernel of links. We study the problem bas

  69. Constantine Yannouleas, Uzi Landman

    Through the introduction of a class of trial wave functions portraying combined rotations and vibrations of molecules formed through particle localization in concentric polygonal rings, a correlated basis is constructed that spans the translationally invariant part of the lower-Landau-level (LLL) spectra. These trial functions, referred to as rovibrational m

  70. Pietro Colangelo, Fulvia De Fazio

    We discuss how to classify the $c{\bar s}$ meson $D_{sJ}(3040)$ recently discovered by the BaBar Collaboration. We consider four possible assignments, together with signatures useful to distinguish among them.

  71. Alessandro Ottazzi, Ben Warhurst

    L. Capogna and M. Cowling showed that if $ϕ$ is 1-quasiconformal on an open subset of a Carnot group G, then composition with $ϕ$ preserves Q-harmonic functions, where Q denotes the homogeneous dimension of G. Then they combine this with a regularity theorem for Q-harmonic functions to show that $ϕ$ is in fact $C^\infty$. As an application, they observe that

  72. R. Decarli, R. Falomo, A. Treves, M. Barattini

    We report the discovery of a quasar close to SDSS J0927+2943 (z = 0.713), which is a massive binary / recoiling black hole candidate. The companion quasar is at a projected distance of 125 h_70^{-1} kpc and exhibits a radial velocity difference of ~1400 km/s with respect to the known quasar. We discuss the nature of this peculiar quasar pair and the properti

  73. B. S. Zou

    Evidence has been accumulating for the existence of significant intrinsic non-perturbative five-quark components in various baryons. The inclusion of the five-quark components gives a natural explanation of the excess of $\bar d$ over $\bar u$, significant quark orbital angular momentum in the proton, the problematic mass and decay pattern of the lowest $1/2

  74. Alessandro Ottazzi

    This thesis was inspired by work of M. Cowling, F. De Mari, A. Koranyi and M. Reimann, who studied multicontact structures for the homogeneous manifolds G/P, where G is a semisimple Lie group and P is the minimal parabolic subgroup of G. The multicontact structure here arises naturally by the nilpotent component N of the Iwasawa decomposition of G, which is

  75. Ricardo Silva

    Discovering latent representations of the observed world has become increasingly more relevant in data analysis. Much of the effort concentrates on building latent variables which can be used in prediction problems, such as classification and regression. A related goal of learning latent structure from data is that of identifying which hidden common causes g

  76. D. Djukanovic, J. Gegelia, S. Scherer

    A parity-conserving and Lorentz-invariant effective field theory of self-interacting massive vector fields is considered. For the interaction terms with dimensionless coupling constants the canonical quantization is performed. It is shown that the self-consistency condition of this system with the second-class constraints in combination with the perturbative

  77. Jing Shu, Peng-fei Yin, Shou-hua Zhu

    We discuss the neutrino constraints from solar and terrestrial dark matter (DM) annihilations in the inelastic dark matter (iDM) scenario after the recent CDMS II results. To reconcile the DAMA/LIBRA data with constraints from all other direct experiments, the iDM needs to be light ($m_χ< 100$ GeV) and have a large DM-nucleon cross section ($σ_n \sim$ 10$^{-

  78. R. S. Penciu, M. Kafesaki, Th. Koschny, E. N. Economou

    Using detailed simulations we investigate the magnetic response of metamaterials consisting of pairs of parallel slabs or combinations of slabs with wires (including the fishnet design) as the length-scale of the structures is reduced from mm to nm. We observe the expected saturation of the magnetic resonance frequency when the structure length-scale goes to

  79. A. Gnerucci, A. Marconi, A. Capetti, D. Axon

    This is the first in a series of papers in which we study the application of spectroastrometry in the context of gas kinematical studies aimed at measuring the mass of supermassive black holes. The spectroastrometrical method consists in measuring the photocenter of light emission in different wavelength or velocity channels. In particular we explore the pot

  80. J. Kacur, B. Malengier, P. Kison

    A novel centrifuge set-up for the study of unsaturated flow characteristics in porous media is examined. In this set-up, simple boundary conditions can be used, but a free moving boundary between unsaturated-saturated flow arises. A precise and numerically efficient approximation is presented for the mathematical model based on Richards&#39; nonlinear and de

  81. Marcella Massardi, Anna Bonaldi, Mattia Negrello, Sara Ricciardi

    We present a new evolutionary model that describes the population properties of radio sources at frequencies <5 GHz, thus complementing the De Zotti et al. (2005) model, holding at higher frequencies. We find that simple analytic luminosity evolution is still sufficient to fit the wealth of available data on local luminosity functions, multi-frequency source

  82. Seung Ki Baek, Sebastian Bernhardsson

    We address the equilibrium concept of a reverse auction game so that no one can enhance the individual payoff by a unilateral change when all the others follow a certain strategy. In this approach the combinatorial possibilities to consider become very much involved even for a small number of players, which has hindered a precise analysis in previous works.

  83. Marko Woelki, Kirone Mallick

    We consider the totally asymmetric simple exclusion process (TASEP) on a finite lattice with open boundaries. We show, using the recursive structure of the Markov matrix that encodes the dynamics, that there exist two transfer matrices $T_{L-1,L}$ and $\tilde{T}_{L-1,L}$ that intertwine the Markov matrices of consecutive system sizes: $\tilde{T}_{L-1,L}M_{L-

  84. Mary Erlund, Andy Fabian, Katherine Blundell, Carolin Crawford

    New Chandra observations have resolved the structure of the X-ray luminous southern hotspot in the giant radio quasar 4C74.26 into two distinct features. The nearer one to the nucleus is an extremely luminous peak, extended some 5 kpc perpendicular to the orientation of the jet; 19 kpc projected further away from the central nucleus than this is a fainter X-

  85. Johannes Gütschow

    Clifford quantum cellular automata (CQCAs) are a special kind of quantum cellular automata (QCAs) that incorporate Clifford group operations for the time evolution. Despite being classically simulable, they can be used as basic building blocks for universal quantum computation. This is due to the connection to translation-invariant stabilizer states and thei

  86. X. Artru

    An elementary recursive model accounting for the quark spin in the fragmentation of a quark into mesons is presented. The quark spin degree of freedom is represented by a two-components spinor. Spin one meson can be included. The model produces Collins effect and jet handedness. The influence of the initial quark polarisation decays exponentially with the ra

  87. Frédéric Hélein, Laurent Hauswirth, Frank Pacard

    We define the notion of an exceptional manifold to be a flat Riemannian manifold with boundary which supports a positive harmonic function satisfying simultaneously a zero Dirichlet condition and a constant (nonzero) Neumann condtion at the boundary. We study the two-dimensional case: we present various examples and give a general construction algorithm of s

  88. Victor Dotsenko, Boris Klumov

    We study the statistical properties of one-dimensional directed polymers in a short-range random potential by mapping the replicated problem to a many body quantum boson system with attractive interactions. We find the full set of eigenvalues and eigenfunctions of the many-body system and perform the summation over the entire spectrum of excited states. The

  89. R. A. Broglia, G. Potel, F. Barranco, E. Vigezzi

    The bare NN-potential, parametrized so as to reproduce the nuclear phase shifts leads to a sizable Cooper pair binding energy in nuclei along the stability valley. It is a much debated matter whether this value accounts for the &#34;empirical&#34; value of the pairing gap or whether a similarly important contribution arises from the exchange of collective vi

  90. F. Hengstberger, M. Eisterer, H. W. Weber

    We analyze the influence of the magnetic field generated by the supercurrents (self-field) on the current density distribution by numerical simulations. The thickness of the superconducting film determines the self-field and consequently the critical current density at zero applied field. We find an equation, which derives the thickness dependence of the cri

  91. Jahan Zahid

    We verify a conjecture of Emil Artin, for the case of a Cubic and Quadratic form over any $p$-adic field, provided the cardinality of the residue class field exceeds 293. That is any Cubic and Quadratic form with at least 14 variables has a non-trivial $p$-adic zero, with the aforementioned condition on the residue class field. A crucial step in the proof, i

  92. James F. Lutsko, Vasileios Basios, Gregoire Nicolis, John J. Kozak

    Recent observations of the growth of protein crystals have identified two different growth regimes. At low supersaturation, the surface of the crystal is smooth and increasing in size due to the nucleation of steps at defects and the subsequent growth of the steps. At high supersaturation, nucleation occurs at many places simultaneously, the crystal surface

  93. C. M. Brunt, C. Federrath, D. J. Price

    We introduce and test an expression for calculating the variance of a physical field in three dimensions using only information contained in the two-dimensional projection of the field. The method is general but assumes statistical isotropy. To test the method we apply it to numerical simulations of hydrodynamic and magnetohydrodynamic turbulence in molecula

  94. Jacek Dziarmaga, Piotr Deuar, Krzysztof Sacha

    We demonstrate that knowledge of two body correlation functions like g2(x) is insufficient to draw conclusions about whether solitons fill in or not in individual experimental runs. In our example, g2 is filled in, while the soliton is not.

  95. Ruqian Lu, Lixing Li, Yun Shang, Xiaoyu Li

    In this paper we introduced an algebraic semantics for process algebra in form of abstract data types. For that purpose, we developed a particular type of algebra, the seed algebra, which describes exactly the behavior of a process within a labeled transition system. We have shown the possibility of characterizing the bisimulation of two processes with the i

  96. Wenxian Zhang, Jun Zhuang

    We investigate with exact numerical calculation coherent control of a two-level quantum system&#39;s decay by subjecting the two-level system to many periodic ideal $2π$ phase modulation pulses. For three spectrum intensities (Gaussian, Lorentzian, and exponential), we find both suppression and acceleration of the decay of the two-level system, depending on

  97. S. I. Fisenko, I. S. Fisenko

    In elaboration of the results presented earlier the red shift is also regarded in this investigation as a widening of electromagnetic radiation spectra, determined by the existence of gravitational radiation of a banded spectrum of the same level as electromagnetic.

  98. A. V. Shorokhov, V. A. Margulis

    We have developed a theory of the one-phonon intraband resonance Raman scattering (IRRS) in anisotropic quantum dots subjected to an arbitrarily directed magnetic field. The differential Raman cross section is obtained. The resonance structure of the Raman cross section is studied. It is shown that the quantum dot subjected in a magnetic field can be used as

  99. Marius Paicu, Arghir Zarnescu

    We study a complex non-newtonian fluid that models the flow of nematic liquid crystals. The fluid is described by a system that couples a forced Navier-Stokes system with a parabolic-type system. We prove the existence of global weak solutions in dimensions two and three. We show the existence of a Lyapunov functional for the smooth solutions of the coupled

  100. Holger Heumann, Ralf Hiptmair

    We consider generalized linear transient convection-diffusion problems for differential forms on bounded domains in $\mathbb{R}^{n}$. These involve Lie derivatives with respect to a prescribed smooth vector field. We construct both new Eulerian and semi-Lagrangian approaches to the discretization of the Lie derivatives in the context of a Galerkin approximat