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November 2006 arXiv papers — page 3

Showing 201–300 of 5,001 papers

  1. I. D. Karachentsev, Yu. N. Kudrya, V. E. Karachentseva, S. N. Mitronova

    The 2MFGC catalog we have used contains 18020 galaxies selected from the extended objects in the 2MASS infrared sky survey as having apparent ratios of the axes b/a<0.3. Most of them are spiral galaxies of later morphological types whose disks are seen almost edge-on. The individual distances to the 2724 2MFGC galaxies with known rotation velocities and radi

  2. A. Miglio, P. -O. Bourge, J. Montalban, M. -A. Dupret

    The discovery of beta Cephei stars in low metallicity environments, as well as the difficulty to theoretically explain the excitation of the pulsation modes observed in some beta Cephei and SPB stars, suggest that the iron opacity ``bump&#39;&#39; provided by standard models could be underestimated. We investigate, by means of a parametric study, the effect

  3. A. Papitto, T. Di Salvo, L. Burderi, M. T. Menna

    We present a precise timing analysis of the accreting millisecond pulsar XTE J1814-338 during its 2003 outburst, observed by RXTE. A full orbital solution is given for the first time; Doppler effects induced by the motion of the source in the binary system were corrected, leading to a refined estimate of the orbital period, P_orb=15388.7229(2)s, and of the p

  4. P. Nurmi, P. Heinämäki, E. Saar, M. Einasto

    If the concordance $Λ$CDM model is a true description of the universe, it should also properly predict the properties and structure of dark matter haloes, where galaxies are born. Using N-body simulations with a broad scale of mass and spatial resolution, we study the structure of dark matter haloes, the distribution of masses and the spatial distribution of

  5. Feng Yuan, Ronald E. Taam R. Misra, Xue-Bing Wu, Yongquan Xue

    Emission spectra of hot accretion disks characteristic of advection dominated accretion flow (ADAF) models are investigated for comparison with the brightest ultra-luminous source, X-1, in the galaxy M82. If the spectral state of the source is similar to the low luminosity hard state of stellar mass black holes in our Galaxy, a fit to the {\it Chandra} X-ray

  6. S. Knop, P. H. Hauschildt, E. Baron

    We present a general method to calculate radiative transfer including scattering in the continuum as well as in lines in spherically symmetric systems that are influenced by the effects of general relativity (GR). We utilize a comoving wavelength ansatz that allows to resolve spectral lines throughout the atmosphere. The used numerical solution is an operato

  7. T. Kotani, K. Kubota, M. Namiki, N. Kawai

    A radio-IR-optical-X-ray observation campaign of SS 433 has been performed in April 2006, when the jet axis is almost perpendicular to the line of sight. Five flares have been detected during the campaign by radio monitoring observation with RATAN-600. The X-ray astronomical satellite Suzaku observed the source in and out of eclipse. In the X-ray data out of

  8. J. Petri

    The physics of the pulsar inner magnetosphere remains poorly constrained by observations. Although about 2000 pulsars have been discovered to date, little is known about their emission mechanism. Large vacuum gaps probably exist and a non-neutral plasma made of electrons in some regions and of positrons in some other regions fills space to form an electrosph

  9. C. Wolf, M. E. Gray, A. Aragon-Salamanca, K. P. Lane

    We investigate correlations between galaxy age and environment in the Abell 901/2 supercluster for separate morphologies. Using COMBO-17 data, we define a sample of 530 galaxies, complete at $M_V -5\log h<-18$ on an area of $3.5\times 3.5$ (Mpc/$h$)$^2$. We explore several age indicators including an extinction-corrected residual from the colour-magnitude re

  10. J. V. Cunha, L. Marassi, J. A. S. Lima

    Estimates of $H_0$ from Sunyaev-Zel&#39;dovich effect (SZE) and X-ray surface brightness of galaxy clusters depends on the underlying cosmology. In the current $Λ$CDM flat cosmology, a possible technique to broke the degenerescency on the mass density parameter ($Ω_{m}$) is to apply a joint analysis involving the baryon acoustic oscillations (BAO). By adopti

  11. Jaime E. Forero-Romero, Jeremy Blaizot, Julien Devriendt, Ludovic Van Waerbeke

    We present the Lensed Mock Map Facility (LeMoMaF), a tool designed to perform mock weak lensing measurements on numerically simulated chunks of the universe. Coupling N-body simulations to a semi-analytical model of galaxy formation, LeMoMaF can create realistic lensed images and mock catalogues of galaxies, at wavelengths ranging from the UV to the submm. T

  12. Michael T. Busha, August E. Evrard, Fred C. Adams

    We explore the effects of small scale structure on the formation and equilibrium of dark matter halos in a universe dominated by vacuum energy. We present the results of a suite of four N-body simulations, two with a LCDM initial power spectrum and two with WDM-like spectra that suppress the early formation of small structures. All simulations are run into t

  13. Brian E. Wood, Vladislav V. Izmodenov, Jeffrey L. Linsky, Yury G. Malama

    We assess what information HST observations of stellar Ly-alpha lines can provide on the heliosheath, the region of the heliosphere between the termination shock and heliopause. To search for evidence of heliosheath absorption, we conduct a systematic inspection of stellar Ly-alpha lines reconstructed after correcting for ISM absorption (and heliospheric/ast

  14. Luciana Bianchi, Lino Rodriguez-Merino, Maurice Viton, Michel Laget

    We use the Galaxy Evolution Explorer (GALEX) Medium and All-Sky-Imaging Survey (MIS & AIS) data from the first public data release (GR1), matched to the Sloan Digital Sky Survey (SDSS) DR3 catalog, to perform source classification. The GALEX surveys provide photometry in far- and near-UV bands and the SDSS in five optical bands (u,g,r,i,z). The GR1/DR3 overl

  15. Vicente Vento

    Dirac showed that the existence of one magnetic pole in the universe could offer an explanation of the discrete nature of the electric charge. Magnetic poles appear naturally in most Grand Unified Theories. Their discovery would be of greatest importance for particle physics and cosmology. The intense experimental search carried thus far has not met with suc

  16. A. H. Barnett, T. Betcke

    We report the first large-scale statistical study of very high-lying eigenmodes (quantum states) of the mushroom billiard proposed by L. Bunimovich in this journal, vol. 11, 802 (2001). The phase space of this mixed system is unusual in that it has a single regular region and a single chaotic region, and no KAM hierarchy. We verify Percival&#39;s conjecture

  17. C. Reichhardt, C. J. Olson Reichhardt

    Using numerical simulations, we demonstrate that superconductors containing periodic pinning arrays which have been diluted through random removal of a fraction of the pins have pronounced commensurability effects at the same magnetic field strength as undiluted pinning arrays. The commensuration can occur at fields significantly higher than the matching fie

  18. Vadas Gintautas, Alfred Hubler

    We present experimental data on the limiting behavior of an interreality system comprising a virtual horizontally driven pendulum coupled to its real-world counterpart, where the interaction time scale is much shorter than the time scale of the dynamical system. We present experimental evidence that if the physical parameters of the simplified virtual system

  19. Chen Wang, Dong Lai

    We study the wave propagation modes in the relativistic streaming pair plasma of the magnetospheres of pulsars and magnetars, focusing on the effect of vacuum polarization. We show that the combined plasma and vacuum polarization effects give rise to a vacuum resonance, where ``avoided mode crossing&#39;&#39; occurs between the extraordinary mode and the (su

  20. Liang Gao, Simon D. M. White

    We use a very large simulation of structure growth in a LCDM universe -- the Millennium Simulation -- to study assembly bias, the fact that the large-scale clustering of haloes of given mass varies significantly with their assembly history. We extend earlier work based on the same simulation by superposing results for redshifts from 0 to 3, by defining a les

  21. Niel de Beaudrap

    The one-way measurement model is a framework for universal quantum computation, in which algorithms are partially described by a graph G of entanglement relations on a collection of qubits. A sufficient condition for an algorithm to perform a unitary embedding between two Hilbert spaces is for the graph G, together with input/output vertices I, O \subset V(G

  22. A. A. Clerk, D. Wahyu Utami

    We demonstrate theoretically how photon number statistics of a driven, damped oscillator at finite temperature can be extracted by measuring the dephasing spectrum of a two-level system dispersively coupled to the oscillator; we thus extend the work of Dykman (1987) and Gambetta et al. (2006). We carefully consider the fidelity of this scheme-- to what exten

  23. Borun D. Chowdhury, Samir D. Mathur

    In the early Universe matter was crushed to high densities, in a manner similar to that encountered in gravitational collapse to black holes. String theory suggests that the large entropy of black holes can be understood in terms of fractional branes and antibranes. We assume a similar physics for the matter in the early Universe, taking a toroidal compactif

  24. C. Carmeli, T. Heinonen, A. Toigo

    The intrinsic unsharpness of a quantum observable is studied by introducing the notion of resolution width. This quantification of accuracy is shown to be closely connected with the possibility of making approximately repeatable measurements. As a case study, the intrinsic unsharpness and approximate repeatability of position and momentum measurements are ex

  25. Kentaro Hanaki, Keisuke Ohashi, Yuji Tachikawa

    We analyze the structure of a particular higher derivative correction of five-dimensional ungauged and gauged supergravity with eight supercharges. Specifically, we determine all the purely bosonic terms which are connected by the supersymmetry transformation to the mixed gauge-gravitational Chern-Simons term, W wedge tr R wedge R. Our construction utilizes

  26. A. C. H. Rowe, D. Paget

    Tunneling between a photo-excited p-type silicon tip and a gold surface is studied as a function of tip bias, tip/sample distance and light intensity. In order to extend the range of application of future spin injection experiments, the measurements are carried out under nitrogen gas at room temperature. It is found that while tunneling of valence band elect

  27. S. J. Colley, G. Kennedy

    J. Kock has previously defined a tangency quantum product on formal power series with coefficients in the cohomology ring of any smooth projective variety, and thus a ring that generalizes the quantum cohomology ring. We further generalize Kock&#39;s construction by defining a dth-order contact product and establishing its associativity.

  28. V. Corless, L. King

    Measuring the distribution of mass on galaxy cluster scales is a crucial test of the Lambda CDM model, providing constraints on the nature of dark matter. Recent work investigating mass distributions of individual galaxy clusters using gravitational lensing has illuminated potential inconsistencies between the predictions of structure formation models relati

  29. Pisin Chen

    The well-known hierarchy between the Planck scale (~10^{19}GeV) and the TeV scale, namely a ratio of ~10^{16} between the two, is coincidentally repeated in a inverted order between the TeV scale and the dark energy scale at \~10^{-3}eV implied by the observations. We argue that this is not a numerical coincidence. The same brane-world setups to address the

  30. Hervé Kunz, Thierry Schuepbach, Marc-André Dupertuis

    We give a method to compute the smooth part of the density of states in a semi-classical expansion, when the Hamiltonian contains a Coulomb potential and non-cartesian coordinates are appropriate. We apply this method to the case of the hydrogen atom in a magnetic field with fixed $z$-component of the angular momentum. This is then compared with numerical re

  31. O. Gühne, P. Hyllus, O. Gittsovich, J. Eisert

    We propose a unifying approach to the separability problem using covariance matrices of locally measurable observables. From a practical point of view, our approach leads to strong entanglement criteria that allow to detect the entanglement of many bound entangled states in higher dimensions and which are at the same time necessary and sufficient for two qub

  32. Suk Bum Chung, Michael Stone

    We construct the wave functions for the Moore-Read $ν= 5/2$ quantum Hall state on a torus in the presence of two quasiholes. These explicit wave functions allow us to compute the monodromy matrix that describes the effect of quasihole motion on the space of degenerate ground states. The result agrees with the recent discussion by Oshikawa {\it et al.} Our ca

  33. Hua Xu, Liangbing Hu, Steven M. Anlage, George Gruner

    The authors measured the transport properties of single-walled carbon nanotube (SWCNT) films in the microwave frequency range from 10 MHz to 30 GHz by using the Corbino reflection technique from temperatures of 20-400 K. Based on the real and imaginary parts of the microwave conductivity, they calculated the shielding effectiveness for various film thickness

  34. Takeshi Chiba, Tristan L. Smith, Adrienne L. Erickcek

    It has been proposed that cosmic acceleration or inflation can be driven by replacing the Einstein-Hilbert action of general relativity with a function f(R) of the Ricci scalar R. Such f(R) gravity theories have been shown to be equivalent to scalar-tensor theories of gravity that are incompatible with Solar System tests of general relativity, as long as the

  35. Qaisar Shafi, Zurab Tavartkiladze

    We introduce a flavor ${\cal U}(1)$ symmetry à la Froggat-Nielsen to explain the magnitude of the CKM mixing angles as well bilarge mixing in the neutrino sector. In the framework of GUTs we also estimate the magnitude of the third leptonic mixing angle $θ_{13}$. Estimates for rare leptonic decays such as $μ\to e \ga $ are also provided. Finally, leptogenesi

  36. O. Lieleg, M. M. A. E. Claessens, C. Heussinger, E. Frey

    While actin bundles are used by living cells for structural fortification, the microscopic origin of the elasticity of bundled networks is not understood. Here, we show that above a critical concentration of the actin binding protein fascin, a solution of actin filaments organizes into a pure network of bundles. While the elasticity of weakly crosslinked net

  37. S. Heinemeyer

    The International Linear e+e- Collider (ILC) could go into operation in the second half of the upcoming decade. Experimental analyses and theory calculations for the physics at the ILC are currently performed. We review recent progress, as presented at the LCWS06 in Bangalore, India, in the fields of Higgs boson physics and top/QCD. Also the area of loop cal

  38. S. Heinemeyer

    Electroweak precision measurements can provide indirect information about the possible scale of supersymmetry already at the present level of accuracy. We review present day sensitivities of precision data in mSUGRA-type models with the gravitino as the lightest supersymmetric particle (LSP). The chi^2 fit is based on M_W, sin^2 theta_eff, (g-2)_mu, BR(b ->

  39. Rajan Amit Mehta

    We approach Mackenzie&#39;s LA-groupoids from a supergeometric point of view by introducing Q-groupoids, which are groupoid objects in the category of Q-manifolds. There is a faithful functor from the category of LA-groupoids to the category of Q-groupoids. We associate to every Q-groupoid a double complex that provides a model for the Q-cohomology of the cl

  40. Cormac Walsh

    We investigate the horofunction boundary of the Hilbert geometry defined on an arbitrary finite-dimensional bounded convex domain D. We determine its set of Busemann points, which are those points that are the limits of `almost-geodesics&#39;. In addition, we show that any sequence of points converging to a point in the horofunction boundary also converges i

  41. Sean Murray, Christian Saemann

    We first review the description of flag manifolds in terms of Pluecker coordinates and coherent states. Using this description, we construct fuzzy versions of the algebra of functions on these spaces in both operatorial and star product language. Our main focus is here on flag manifolds appearing in the double fibration underlying the most common twistor cor

  42. Jorge Portoles, Ignasi Rosell, Pedro Ruiz-Femenia

    The construction of a resonance theory involving hadrons requires implementing the information from higher scales into the couplings of the effective Lagrangian. We consider the large-Nc chiral resonance theory incorporating scalars and pseudoscalars, and we find that, by imposing LO short-distance constraints on form factors of QCD currents constructed with

  43. A. O. Barvinsky, A. Yu. Kamenshchik, C. Kiefer, D. V. Nesterov

    We apply a recently suggested technique of the Neumann-Dirichlet reduction to a toy model of brane-induced gravity for the calculation of its quantum one-loop effective action. This model is represented by a massive scalar field in the $(d+1)$-dimensional flat bulk supplied with the $d$-dimensional kinetic term localized on a flat brane and mimicking the bra

  44. N. J. Stone, J. R. Stone, M. Lindroos, P. Richards

    The recent suggestion that dramatic changes may occur in the lifetime of alpha and beta decay when the activity, in a pure metal host, is cooled to a few Kelvin, is examined in the light of published low temperature nuclear orientation (LTNO) experiments, with emphasis here on alpha decay. In LTNO observations are made of the anisotropy of radioactive emissi

  45. M. Magdalena Rodriguez

    A very interesting problem in the classical theory of minimal surfaces consists of the classification of such surfaces under some geometrical and topological constraints. In this short paper, we give a brief summary of the known classification results for properly embedded minimal surfaces with genus zero in $\mathbb{R}^3$ or quotients of $\mathbb{R}^3$ by o

  46. Sangbum Cho, Darryl McCullough

    We present a new theory which describes the collection of all tunnels of tunnel number 1 knots in the 3-sphere (up to orientation-preserving equivalence in the sense of Heegaard splittings) using the disk complex of the genus-2 handlebody and associated structures. It shows that each knot tunnel is obtained from the tunnel of the trivial knot by a uniquely d

  47. Dai G. Yamazaki, Kiyotomo Ichiki, Ken-ichi Umezu, Hidekazu Hanayama

    Magnetic field plays a very important role in many astronomical phenomena at various scales of the universe. It is no exception in the early universe. Since the energy density, pressure, and tension of the primordial magnetic field affect gravitational collapses of plasma, the formation of seeds for large scale structures should be influenced by them. Here w

  48. Giulio Bonelli, Alessandro Tanzini, Maxim Zabzine

    We define a topological quantum membrane theory on a seven dimensional manifold of $G_2$ holonomy. We describe in detail the path integral evaluation for membrane geometries given by circle bundles over Riemann surfaces. We show that when the target space is $CY_3\times S^1$ quantum amplitudes of non-local observables of membranes wrapping the circle reduce

  49. Françoise Détienne

    This paper presents a state-of-art review of empirical research on object-oriented (OO) design. Many claims about the cognitive benefits of the OO paradigm have been made by its advocates. These claims concern the ease of designing and reusing software at the individual level as well as the benefits of this paradigm at the team level. Since these claims are

  50. Patrick D&#39;Astous, Françoise Détienne, Willemien Visser, Pierre Robillard

    By contrast to design meetings, design evaluation meetings (DEMs) have generally been considered as situations in which, according to DEMs methodologies, design activities are quite marginal. In a study of DEMs in software development, i.e. in technical review meetings following a particular review methodology, we showed: (i) the occurrence of design activit

  51. Jozsef Garai

    Based on two assumptions, the surface layer is flexible, and the internal energy of the latent heat of vaporization is completely utilized by the atoms for overcoming on the surface resistance of the liquid, the enthalpy of vaporization was calculated for 45 elements. The theoretical values were tested against experiments with positive result.

  52. Martin Hock, Boaz Tsaban

    We give a systematic exposition of memory-length algorithms for solving equations in noncommutative groups. This exposition clarifies some points untouched in earlier expositions. We then focus on the main ingredient in these attacks: Length functions. After a self-contained introduction to Garside groups, we describe length functions induced by the greedy n

  53. Kyrill A. Bugaev

    The relativistic equation of state (EOS) of the Van-der-Waals gas is suggested and analyzed. In contrast to the usual case, the Lorentz contraction of the sphere&#39;s volume is taken into account. It is proven that the suggested EOS obeys the causality in the limit of high densities, i.e., the value of sound velocity of such a media is subluminar. The press

  54. Scipio Cuccagna

    We extend a result on dispersion for solutions of the linear Schrödinger equation, proved by Firsova for operators with finitely many energy bands only, to the case of smooth potentials in 1D with infinitely many bands. The proof consists in an application of the method of stationary phase. Estimates for the phases, essentially the band functions, follow fro

  55. Françoise Détienne, Géraldine Martin, Elisabeth Lavigne

    We present a field study aimed at analysing the use of viewpoints in co-design meetings. A viewpoint is a representation characterised by a certain combination of constraints. Three types of viewpoints are distinguished: prescribed viewpoint, discipline-specific viewpoint and integrated viewpoint. The contribution of our work consists in characterising the v

  56. Françoise Détienne

    This paper focuses on two characteristics of collaborative design with respect to cooperative work: the importance of work interdependencies linked to the nature of design problems; and the fundamental function of design cooperative work arrangement which is the confrontation and combination of perspectives. These two intrinsic characteristics of the design

  57. K. Nakayama, Yongseok Oh, J. Haidenbauer, T. -S. H. Lee

    It is shown that the relative sign between the $NNω$ and $πρω$ coupling constants can be determined most sensitively from $ω$ production processes in $NN$ collisions. Recent data on these reactions clearly favor the sign of the $πρω$ coupling constant which is opposite to that inferred from studies of the photoproduction reaction in combination with the vect

  58. Paolo Sibani

    We study the intermittent behavior of the energy decay and linear magnetic response of a glassy system during isothermal aging after a deep thermal quench using the Edward-Anderson spin glass model as a paradigmatic example. The large intermittent changes in the two observables are found to occur in a correlated fashion and through irreversible bursts, `quak

  59. Chong-Sun Chu, Shou-Huang Dai

    We consider black ring with a cosmological constant in the five dimensional N=4 de Sitter supergravity theory. Our solution preserves half of the de Sitter supersymmetries and has one rotation symmetry. Unlike the flat case, there is no angular momentum and the stability against gravitational self-attraction is balanced by the cosmological repulsion due to t

  60. Ezequiel Alvarez, Alejandro Szynkman

    In this letter we reinterpret and reanalyze the available data of the B meson factories showing the existence of direct experimental evidence of time reversal invariance violation in B mesons. This reinterpretation consists of using the available observables to define a new observable which, in a model independent way and without assuming CPT invariance, com

  61. Sebastian de Haro, Ioannis Papadimitriou, Anastasios C. Petkou

    We show that a scalar field conformally coupled to AdS gravity in four dimensions with a quartic self-interaction can be embedded into M-theory. The holographic effective potential is exactly calculated, allowing us to study non-perturbatively the stability of AdS_4 in the presence of the conformally coupled scalar. It is shown that there exists a one-parame

  62. Martin White, Zheng Zheng, Michael J. I. Brown, Arjun Dey

    The formation and evolution of massive red galaxies form a crucial test of theories of galaxy formation based on hierarchical assembly. In this letter we use observations of the clustering of luminous red galaxies from the Bootes field and N-body simulations to argue that about 1/3 of the most luminous satellite galaxies appear to undergo merging or disrupti

  63. Eddy Yusuf, B. J. Powell, Ross H. McKenzie

    We give a quantitative analysis of the published results of nuclear magnetic resonance (NMR) experiments for k-(ET)2X family of organic charge transfer salts by using the phenomenological spin fluctuation model of Moriya, and Millis, Monien and Pines (M-MMP). For temperatures above T_NMR ~ 50 K, the model gives a good quantitative description of the data for

  64. Kyu-Hyun Chae

    We improve strong lensing constraints on cosmological parameters in light of the new measurement of the velocity dispersion function of early-type galaxies based on the SDSS DR5 data and recent semi-analytical modeling of galaxy formation. Using both the number statistics of the CLASS statistical sample and the image separation distribution of the CLASS and

  65. G. Gogoberidze

    A novel model of incompressible magnetohydrodynamic turbulence in the presence of a strong external magnetic field is proposed for explanation of recent numerical results. According to the proposed model, in the presence of the strong external magnetic field, incompressible magnetohydrodynamic turbulence becomes nonlocal in the sense that low frequency modes

  66. Raoul Dillenschneider, Jean Richert

    We implement a Chern-Simons (CS) contribution into the compact QED3 description of the antiferromagnetic Heisenberg model in two dimensions at zero temperature. The CS term allows for the conservation of the SU(2) symmetry of the quantum spin system and fixes the flux through a plaquette to be a multiple of pi as was shown by Marston. We work out the string

  67. Philippe de Forcrand

    The topological structure of the QCD vacuum can be probed by monitoring the spatial localization of the low-lying Dirac eigenmodes. This approach can be pursued on the lattice, and unlike the traditional one requires no smoothing of the gauge field. I review recent lattice studies, attempting to extract a consistent description. What emerges is a picture of

  68. Saket Sathe

    A useful method for representing Bayesian classifiers is through \emph{discriminant functions}. Here, using copula functions, we propose a new model for discriminants. This model provides a rich and generalized class of decision boundaries. These decision boundaries significantly boost the classification accuracy especially for high dimensional feature space

  69. Benjamin B. Schmidt, Matthias H. Hettler, Gerd Schön

    We investigate the electron (hole) transport through short double-stranded DNA wires in which the electrons are strongly coupled to the specific vibrational modes (vibrons) of the DNA. We analyze the problem starting from a tight-binding model of DNA, with parameters derived from ab-initio calculations, and describe the dissipative transport by equation-of-m

  70. Assadollah Niknam, Kamran Sharifi

    In this paper the concept of unbounded Fredholm operators on Hilbert C*- modules over an arbitrary C*-algebra is discussed and the Atkinson theorem is generalized for bounded and unbounded Feredholm operators on Hilbert C*-modules over C*-algebras of compact operators. In the framework of Hilbert C*-modules over C*-algebras of compact operators, the index of

  71. Jingzhong Zhang, Yong Feng

    Numerical approximate computation can solve large and complex problems fast. It has the advantage of high efficiency. However it only gives approximate results, whereas we need exact results in many fields. There is a gap between approximate computation and exact results. In this paper, we build a bridge by which exact results can be obtained by numerical ap

  72. Belkacem Abdous, Anne-Laure Fougères, Kilani Ghoudi, Philippe Soulier

    Let $(X,Y)$ be a random vector whose conditional excess probability $θ(x,y):=P(Y\leq y | X>x)$ is of interest. Estimating this kind of probability is a delicate problem as soon as $x$ tends to be large, since the conditioning event becomes an extreme set. Assume that $(X,Y)$ is elliptically distributed, with a rapidly varying radial component. In this paper,

  73. Qiang Yuan, Xiao-Jun Bi

    In this paper we calculate the Galactic positron flux from dark matter annihilation in the frame of supersymmetry, taking the enhancement of the flux by existence of dark matter substructures into account. The propagation of positrons in the Galactic magnetic field is solved in a realistic numerical model GALPROP. The secondary positron flux is recalculated

  74. Florian Schaetz

    We present a connection between the BFV-complex (abbreviation for Batalin-Fradkin-Vilkovisky complex) and the so-called strong homotopy Lie algebroid associated to a coisotropic submanifold of a Poisson manifold. We prove that the latter structure can be derived from the BFV-complex by means of homotopy transfer along contractions. Consequently the BFV-compl

  75. Yuliya Mishura, Esko Valkeila

    Assume that $X$ is a continuous square integrable process with zero mean, defined on some probability space $(Ω,\mathrm {F},\mathrm {P})$. The classical characterization due to P. Lévy says that $X$ is a Brownian motion if and only if $X$ and $X_t^2-t$, $t\ge0,$ are martingales with respect to the intrinsic filtration $\mathrm {F}^X$. We extend this result t

  76. S. Galatolo

    We prove that if a system has superpolynomial (faster than any power law) decay of correlations then the time $τ_{r}(x,x_{0})$ needed for a typical point $x$ to enter for the first time a ball $B(x_{0},r)$ centered in $x_{0},$ with small radius $r$ scales as the local dimension at $x_{0},$ i.e. $$\underset{r\to 0}{\lim}\frac{\log τ_{r}(x,x_{0})}{-\log r}=d_{

  77. Hui Hu, Xia-Ji Liu

    We study theoretically two spatially separate quasi-one-dimensional atomic Fermi gases in a double-well trap. By tuning independently their spin polarizations, a Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) superfluid or a Bardeen-Cooper-Schrieffer (BCS) superfluid may be formed in each well. We seek the possibility of creating a spatially tunable atomic Josephso

  78. Yusuke Iguchi, Takeo Hoshi, Takeo Fujiwara

    A model for formation of helical multishell gold nanowires is proposed and is confirmed with the quantum mechanical molecular dynamics simulations. The model can explain the magic number of the helical gold nanowires in the multishell structure. The reconstruction from ideal non-helical to realistic helical nanowires consists of two stages: dissociations of

  79. Umesh V. Dubey, Amritanshu Prasad, Pooja Singla

    The centralizer algebra of a matrix consists of those matrices that commute with it. We investigate the basic representation-theoretic invariants of centralizer algebras, namely their radicals, projective indecomposable modules, injective indecomposable modules, simple modules and Cartan matrices. With the help of our Cartan matrix calculations we determine

  80. Roderich Tumulka

    In a recent paper [quant-ph/0604079], Conway and Kochen claim to have established that theories of the GRW type, i.e., of spontaneous wave function collapse, cannot be made relativistic. On the other hand, relativistic GRW-type theories have already been presented, in my recent paper [quant-ph/0406094] and by Dowker and Henson [J. Statist. Phys. 115: 1327 (2

  81. Toshio Oshima

    We classify isomorphic classes of the homomorphisms of a root system $Ξ$ to a root system $Σ$ which do not change Cartan integers. We examine several types of isomorphic classes defined by the Weyl group of $Σ$, that of $Ξ$ and the automorphisms of $Σ$ or $Ξ$ etc. We also distinguish the subsystem generated by a subset of a fundamental system. We introduce t

  82. E. Majernikova, Serge Shpyrko

    The long-range spectral density correlations (spectral rigidities $\barΔ_3(\bar n)$ and related spectral compressibilities) of the $E\otimes (b_1+b_2)$ Jahn-Teller model are found strongly nonuniversal with respect to the Hamiltonian parameters and inhomogeneous with respect to the choice of a partial energy segment. However, the spectral compressibilities f

  83. Sarika Jalan, Jayendra N. Bandyopadhyay

    We analyze eigenvalues fluctuations of the Laplacian of various networks under the random matrix theory framework. Analyses of random networks, scale-free networks and small-world networks show that nearest neighbor spacing distribution of the Laplacian of these networks follow Gaussian orthogonal ensemble statistics of random matrix theory. Furthermore, we

  84. H. M. Chan, S. T. Tsou

    In spite of its many successes, the Standard Model makes many empirical assumptions in the Higgs and fermion sectors for which a deeper theoretical basis is sought. Starting from the usual gauge symmetry $u(1) \times su(2) \times su(3)$ plus the 3 assumptions: (A) scalar fields as vielbeins in internal symmetry space \cite{framevec}, (B) the ``confinement pi

  85. Fritz Gesztesy, Helge Holden, Johanna Michor, Gerald Teschl

    We provide a detailed derivation of all complex-valued algebro-geometric finite-band solutions of the Ablowitz-Ladik hierarchy. In addition, we survey a recursive construction of the Ablowitz-Ladik hierarchy and its zero-curvature and Lax formalism.

  86. Xi-Feng Ren, Guo-Ping Guo, Yun-Feng Huang, Zhi-Wei Wang

    Quadrate hole array is explored to study the influence of unsymmetrical periodicity on extraordinary optical transmission through periodic arrays of subwavelength holes. It is found that the transmission efficiency of light and the ratio between transmission efficiencies of horizontal and vertical polarized light can be continuously tuned by rotating the qua

  87. Raju Renjit. G

    This submission has been withdrawn at the request of the author.

  88. Theodor Pribulla, Slavek M. Rucinski, George Conidis, Heide DeBond

    Radial-velocity measurements and sine-curve fits to the orbital radial velocity variations are presented for ten close binary systems: OO Aql, CC Com, V345 Gem, XY Leo, AM Leo, V1010 Oph, V2612 Oph, XX Sex, W UMa, and XY UMa. Most of these binaries have been observed spectroscopically before, but our data are of higher quality and consistency than in the pre

  89. Anirban Saha, Anisur Rahaman, Pradip Mukherjee

    The paper has been withdrawn by the authors. The contents of the paper will be used in a future communication which will contain major addition and shift of focus.

  90. Meng Chen, Lei Zhu

    There are many examples of 3-folds of general type with $χ(\mathcal {O})=1$ found by Iano-Fletcher and Reid about twenty years ago. Iano-Fletcher has ever proved $P_{12}(X)\ge 1$ and $P_{24}(X)\ge 2$ for all minimal 3-folds $X$ of general type with $χ(\mathcal {O}_X)=1$. In this paper, we improve on Fletcher&#39;s method. Our main result is that $ϕ_m$ is bir

  91. M. Yoshimura

    We explore a possibility of measuring the magnitude and the Majorana nature of neutrino masses, by using a novel process of neutrino pair emission from excited atoms. Except lepton number non-conserving processes, the neutrino pair ($ν\barν$) emission is the unique process to distinguish the Majorana neutrino from the Dirac neutrino. The small energy differe

  92. Simeon Hellerman, Ian Swanson

    We study quintessence-driven, spatially flat, expanding FRW cosmologies that arise naturally from string theory formulated in a supercritical number of spacetime dimensions. The tree-level potential of the string theory produces an equation of state at the threshold between accelerating and decelerating cosmologies, and the resulting spacetime is globally co

  93. S. P. Knurenko, A. A. Ivanov, M. I. Pravdin, A. V. Sabourov

    Experimental data obtained at the Yakutsk array after the modernization in 1993 are analyzed. The characteristics of EAS longitudinal and radial development found from the charged particle flux and EAS Cherenkov light registered at the Yakutsk complex array are presented. The energy spectrum of EAS obtained from Cherenkov light and an estimate of the PCR mas

  94. R. Z. Wang, H. Yan, B. Wang, X. W. Zhang

    Field electron emission from an ultrathin multilayer planar cold cathode (UMPC) including quantum well structure has been both experimentally and theoretically investigated. We found that only tuning the energy levels of UMPC the field electron emission (FE) characteristic can be evidently improved, which is unexplained by the conventional FE mechanism. Fiel

  95. Shu Luo, Zhi-zhong Xing

    We consider an effective Majorana neutrino mass operator with the Friedberg-Lee symmetry; i.e., it is invariant under the transformation ν_α-> ν_α+ z (for α= e, μ, τ) with z being a space-time independent constant element of the Grassmann algebra. We show that this new flavor symmetry can be broken in such a nontrivial way that the lightest neutrino remains

  96. Lei Ying, Sichao Yang, R. Srikant

    In this paper, we investigate the delay-throughput trade-offs in mobile ad-hoc networks under two-dimensional i.i.d. mobility models. We consider two mobility time-scales: (i) Fast mobility where node mobility is at the same time-scale as data transmissions; (ii) Slow mobility where node mobility is assumed to occur at a much slower time-scale than data tran

  97. Shengtian Yang, Yan Chen, Peiliang Qiu

    A general lossless joint source-channel coding (JSCC) scheme based on linear codes and random interleavers for multiple-access channels (MACs) is presented and then analyzed in this paper. By the information-spectrum approach and the code-spectrum approach, it is shown that a linear code with a good joint spectrum can be used to establish limit-approaching l

  98. Bahram Mashhoon

    The nonlocal theory of accelerated systems is extended to the propagation of Dirac particles. The implications of nonlocality for the phenomenon of spin-rotation coupling are discussed. The Lorentz-invariant nonlocal Dirac equation is presented for certain special classes of accelerated observers.

  99. Neil Lambert, Peter West

    We study the higher derivative corrections that occur in type II superstring theories in ten dimensions or less. Assuming invariance under a discrete duality group G(Z) we show that the generic functions of the scalar fields that occur can be identified with automorphic forms. We then give a systematic method to construct automorphic forms from a given group

  100. Olivier Giraud

    We calculate analytic expressions for the distribution of bipartite entanglement for pure random quantum states. All moments of the purity distribution are derived and an asymptotic expansion for the purity distribution itself is deduced. An approximate expression for moments and distribution of Meyer-Wallach entanglement for random pure states is then obtai