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September 2009 arXiv papers — page 16

Showing 1,5011,600 of 5,691 papers

  1. David I. Spivak

    Networks are often studied as graphs, where the vertices stand for entities in the world and the edges stand for connections between them. While relatively easy to study, graphs are often inadequate for modeling real-world situations, especially those that include contexts of more than two entities. For these situations, one typically uses hypergraphs or sim

  2. R. Riffel, M. G. Pastoriza, A. Rodriguez-Ardila, C. Bonatto

    We employ IRTF SpeX NIR (0.8--2.4mu m) spectra to investigate the stellar population (SP), active galactic nuclei (AGN), featureless continuum (FC) and hot dust properties in 9 Sy1 and 15 Sy2 galaxies. Both the {\sc starlight} code and the hot dust as an additional base element were used for the first time in this spectral range. Our synthesis shows signific

  3. Marco Santagiustina, Luca Schenato

    A systematic study of the effects of polarization mode dispersion on broad-band and narrow-band, single pump, fiber parametric amplifiers is realized through numerical solutions of the equations governing the interaction. The nonlinear polarization rotation is shown to be a relevant effect that can increase gain randomness when it mixes with polarization mod

  4. Michael P. Fitzgerald, Paul Kalas, James R. Graham

    A point source observed 8 AU in projection from beta Pictoris in L' (3.8 micron) imaging in 2003 has been recently presented as a planet candidate. Here we show the results of L'-band adaptive optics imaging obtained at Keck Observatory in 2008. We do not detect beta Pic b beyond a limiting radius of 0.29 arcsec, or 5.5 AU in projection, from the sta

  5. S. S. R. Offner, C. E. Hansen, M. R. Krumholz

    The kinematics of newly-formed star clusters are interesting both as a probe of the state of the gas clouds from which the stars form, and because they influence planet formation, stellar mass segregation, cluster disruption, and other processes controlled in part by dynamical interactions in young clusters. However, to date there have been no attempts to us

  6. E. Le Floc'h, H. Aussel, O. Ilbert, L. Riguccini

    We present the first results obtained from the identification of ~30,000 sources in the 24mic observations of the COSMOS field at S24>~80muJy. Using accurate photo-z's and extrapolations of the counts at faint fluxes we resolve with unprecedented detail the build-up of the mid-IR background across cosmic ages. We find that ~50% and ~80% of the 24mic back

  7. Marcel Zemp

    We review results from recent high resolution cosmological structure formation simulations, namely the Via Lactea I & II and GHALO projects. These simulations study the formation of Milky Way sized objects within a cosmological framework. We discuss the general properties of cold dark matter halos at redshift z = 0 and focus on new insights into the structur

  8. C. S. Kochanek

    For typical models of binary statistics, 50-70% of core-collapse supernova (ccSN) progenitors are members of a stellar binary at the time of the explosion. Independent of any consequences of mass transfer, this has observational consequences that can be used to study the binary properties of massive stars. In particular, the secondary companion to the progen

  9. Cody Raskin, Evan Scannapieco, James Rhoads, Massimo Della Valle

    The time delay between the formation of a population of stars and the onset of type Ia supernovae (SNe Ia) sets important limits on the masses and nature of SN Ia progenitors. Here we use a new observational technique to measure this time delay by comparing the spatial distributions of SNe Ia to their local environments. Previous work attempted such analyses

  10. Mirjam Cvetič, James Halverson, Robert Richter

    We investigate phenomenologically viable four- and five-stack MSSM D-brane quivers which exhibit realistic fermion mass hierarchies. In our analysis, the mass hierarchies arise either from higher order terms containing the VEV's of SM singlets or from D-instanton effects, where the latter utilizes either family splitting or a factorizable Yukawa matrix.

  11. Shahram Saeidi

    We show that the variational inequality $VI(C,A)$ has a unique solution for a relaxed $(γ, r)$-cocoercive, $μ$-Lipschitzian mapping $A: C\to H$ with $r>γμ^2$, where $C$ is a nonempty closed convex subset of a Hilbert space $H$. From this result, it can be derived that, for example, the recent algorithms given in the references of this paper, despite their be

  12. David Parker

    Since the original proposal of an unconventional chiral order parameter in the ruthenate perovskite superconductor Sr$_{2}$RuO$_{4}$, much attention has been given to the possibility of out-of-plane nodal lines on the predominant $γ$ cylindrical Fermi surface given evidence for low-lying quasiparticle excitations in this material. Here I propose a tunneling

  13. Andrew C. Collazzi, Bradley E. Schaefer, Limin Xiao, Ashley Pagnotta

    In 1975, E. R. Robinson conducted the hallmark study of the behavior of classical nova light curves before eruption, and this work has now become part of the standard knowledge of novae. He made three points; that 5 out of 11 novae showed pre-eruption rises in the years before eruption, that one nova (V446 Her) showed drastic changes in the variability acros

  14. A. Le Fevre, J. Aichelin, C. Hartnack, J. Lukasik

    Recently, is has been observed that events with the {\it same} total transverse energy of light charged particles (LCP) in the quasi target region, $E_{\perp 12}^{QT}$, show two quite distinct reaction scenarios in the projectile domain: multifragmentation and residue production. This phenomenon has been dubbed "bimodality". Using Quantum Molecular D

  15. Ernesto Gonzalez-Candela, Victor Romero-Rochin

    We propose a model for protein folding in vivo based on a Brownian-ratchet mechanism in the multidimensional energy landscape space. The device is able to produce directed transport taking advantage of the assumed intrinsic asymmetric properties of the proteins and employing the consumption of energy provided by an external source. Through such a directed tr

  16. Dilip G Banhatti

    We bring out the identity between two ways of defining a single parameter to combine positional & strength asymmetries of extended extragalactic double radio sources associated with active galaxies. Thus, (r.s - 1)/[(1 + r).(1 + s)], combining arm ratio r (defined to be <= 1, i.e., shorter to longer arm) & strength ratio s (in the sense closer to farther, so

  17. R. Escobedo, M. Carretero, L. L. Bonilla, G. Platero

    Strongly nonlinear transport through Diluted Magnetic Semiconductor multiquantum wells occurs due to the interplay between confinement, Coulomb and exchange interaction. Nonlinear effects include the appearance of spin polarized stationary states and self-sustained current oscillations as possible stable states of the nanostructure, depending on its configur

  18. G. Fritz Benedict, Barbara E. McArthur, Ralf Napiwotzki, Thomas E. Harrison

    We present absolute parallaxes and relative proper motions for the central stars of the planetary nebulae NGC 6853 (The Dumbbell), NGC 7293 (The Helix), Abell 31, and DeHt 5. This paper details our reduction and analysis using DeHt 5 as an example. We obtain these planetary nebula nuclei (PNNi) parallaxes with astrometric data from Fine Guidance Sensors FGS

  19. Harry Bunt, Laurent Romary

    Multimodal interfaces, combining the use of speech, graphics, gestures, and facial expressions in input and output, promise to provide new possibilities to deal with information in more effective and efficient ways, supporting for instance: - the understanding of possibly imprecise, partial or ambiguous multimodal input; - the generation of coordinated, cohe

  20. S. Meloni, A. Arenas, Y. Moreno

    The study of complex networks sheds light on the relation between the structure and function of complex systems. One remarkable result is the absence of an epidemic threshold in infinite-size scale-free networks, which implies that any infection will perpetually propagate regardless of the spreading rate. The vast majority of current theoretical approaches a

  21. James A. Mingo, Roland Speicher

    We provide a simple algorithm for finding the optimal upper bound for sums of products of matrix entries of the form S_pi(N) := sum_{j_1, ..., j_2m = 1}^N t^1_{j_1 j_2} t^2_{j_3 j_4} ... t^m_{j_2m-1 j_2m} where some of the summation indices are constrained to be equal. The upper bound is easily obtained from a graph G associated to the constraints in the sum

  22. Jie Chen, Ilya Safro

    We present a simple iterative strategy for measuring the connection strength between a pair of vertices in a graph. The method is attractive in that it has a linear complexity and can be easily parallelized. Based on an analysis of the convergence property, we propose a mutually reinforcing model to explain the intuition behind the strategy. The practical ef

  23. Ameya Pitale

    We obtain explicit formulas for the test vector in the Bessel model and derive the criteria for existence and uniqueness for Bessel models for the unramified, quadratic twists of the Steinberg representation πof GSp(4,F), where F is a non-archimedean local field of characteristic zero. We also give precise criteria for the Iwahori spherical vector in πto be

  24. Simone Giombi, Vasily Pestun

    We extend the recent conjecture on the relation between a certain 1/8 BPS subsector of 4d N=4 SYM on S^2 and 2d Yang-Mills theory by turning on circular 1/2 BPS &#39;t Hooft operators linked with S^2. We show that localization predicts that these &#39;t Hooft operators and their correlation functions with Wilson operators on S^2 are captured by instanton con

  25. Harsha Raichur, Biswajit Paul

    It has long been argued that better timing precision allowed by satelites like Rossi X-ray Timing Experiments (RXTE) will allow us to measure the orbital eccentricity and the angle of periastron of some of the bright persistent high mass X-ray binaries (HMXBs) and hence a possible measurement of apsidal motion in these system. Measuring the rate of apsidal m

  26. Daniel Alpay, Haim Attia, David Levanony

    Using the white noise space framework, we define a class of stochastic processes which include as a particular case the fractional Brownian motion and its derivative. The covariance functions of these processes are of a special form, studied by Schoenberg, von Neumann and Krein.

  27. Victor Dominguez, Norbert Heuer, Francisco-Javier Sayas

    In this paper we study the Hilbert scales defined by the associated Legendre functions for arbitrary integer values of the parameter. This problem is equivalent to study the left-definite spectral theory associated to the modified Legendre equation. We give several characterizations of the spaces as weighted Sobolev spaces and prove identities among the spac

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

    A solution of the radiative-transfer problem in arbitrary velocity fields introduced in a previous paper, has limitations in its applicability. For large-scale applications, the methods described also require large memory sets that are commonly not available to state-of-the-art computing hardware. In this work, we modify the algorithm to allow the computatio

  29. Sebastian Matera, Karsten Reuter

    We assess heat and mass transfer limitations in in situ studies of model catalysts with a first-principles based multiscale modeling approach that integrates a detailed description of the surface reaction chemistry and the macro-scale flow structures. Using the CO oxidation at RuO2(110) as a prototypical example we demonstrate that factors like a suppressed

  30. H. Bursztyn, V. Dolgushev, S. Waldmann

    This paper deals with two aspects of the theory of characteristic classes of star products: first, on an arbitrary Poisson manifold, we describe Morita equivalent star products in terms of their Kontsevich classes; second, on symplectic manifolds, we describe the relationship between Kontsevich&#39;s and Fedosov&#39;s characteristic classes of star products.

  31. Mikhail Kamenskii, Oleg Makarenkov, Paolo Nistri

    By means of a linear scaling of the variables we convert a singular bifurcation equation in $\R^n$ into an equivalent equation to which the classical implicit function theorem can be directly applied. This allows to deduce the existence of a unique branch of solutions as well as a relevant property of the spectrum of the derivative of the singular bifurcatio

  32. M. R. Bate, G. Lodato, J. E. Pringle

    We investigate the evolution of the relative angle between the stellar rotation axis and the circumstellar disc axis of a star that forms in a stellar cluster from the collapse of a turbulent molecular cloud. This is an inherently chaotic environment with variable accretion, both in terms of rate and the angular momentum of the material, and dynamical intera

  33. Mathias Duckheim, Daniel Loss, Matthias Scheid, Klaus Richter

    We calculate the electrically induced spin accumulation in diffusive systems due to both Rashba (with strength $\alpha)$ and Dresselhaus (with strength $\beta)$ spin-orbit interaction. Using a diffusion equation approach we find that magnetoelectric effects disappear and that there is thus no spin accumulation when both interactions have the same strength, $

  34. Eduardo S. Pereira, Oswaldo D. Miranda

    In this work, we consider the stochastic background of gravitational waves (SBGWs) produced by pre-galactic stars, which form black holes in scenarios of structure formation. The calculation is performed in the framework of hierarchical structure formation using a Press-Schechter-like formalism. Our model reproduces the observed star formation rate at redshi

  35. De-Jun Feng

    Let $π:X\to Y$ be a factor map, where $(X,σ_X)$ and $(Y,σ_Y)$ are subshifts over finite alphabets. Assume that $X$ satisfies weak specification. Let $\ba=(a_1,a_2)\in \R^2$ with $a_1>0$ and $a_2\geq 0$. Let $f$ be a continuous function on $X$ with sufficient regularity (Hölder continuity, for instance). We show that there is a unique shift invariant measure

  36. Marco Santagiustina, Luca Schenato, Carlo Giacomo Someda

    Efficient slow and fast light fiber devices based on narrow band optical parametric amplification require a strict polarization control of the waves involved in the interaction. The use of high birefringence and spun fibers is studied theoretically, possible impairments evaluated, and design parameters determined.

  37. Rui Dilão, Daniele Muraro

    We present a general methodology in order to build mathematical models of genetic regulatory networks. This approach is based on the mass action law and on the Jacob and Monod operon model. The mathematical models are built symbolically by the \emph{Mathematica} software package \emph{GeneticNetworks}. This package accepts as input the interaction graphs of

  38. Julien Barral, De-Jun Feng

    Let $(X,T)$ and $(Y,S)$ be two subshifts so that $Y$ is a factor of $X$. For any asymptotically sub-additive potential $Φ$ on $X$ and $\ba=(a,b)\in\R^2$ with $a>0$, $b\geq 0$, we introduce the notions of $\ba$-weighted topological pressure and $\ba$-weighted equilibrium state of $Φ$. We setup the weighted variational principle. In the case that $X, Y$ are fu

  39. D. R. Heath-Brown, D. Testa

    We prove upper bounds for the number of rational points on non-singular cubic curves defined over the rationals. The bounds are uniform in the curve and involve the rank of the corresponding Jacobian. The method used in the proof is a combination of the &#34;determinant method&#34; with an m-descent on the curve.

  40. D. Batcheldor, A. M. Koekemoer

    (Abridged) The repeated discovery of supermassive black holes (SMBHs) at the centers of galactic bulges, and the discovery of relations between the SMBH mass (M) and the properties of these bulges, has been fundamental in directing our understanding of both galaxy and SMBH formation and evolution. However, there are still many questions surrounding the SMBH

  41. Konrad J. Swanepoel

    A hollow axis-aligned box is the boundary of the cartesian product of $d$ compact intervals in R^d. We show that for d\geq 3, if any 2^d of a collection of hollow axis-aligned boxes have non-empty intersection, then the whole collection has non-empty intersection; and if any 5 of a collection of hollow axis-aligned rectangles in R^2 have non-empty intersecti

  42. P. Simon

    We show some basic facts about dp-minimal ordered structures. The main results are : dp-minimal groups are abelian-by-finite-exponent, in a divisible ordered dp-minimal group, any infinite set has non-empty interior, and any theory of pure tree is dp-minimal.

  43. U. Filobello, A. de la Macorra

    We study the cosmological evolution of a tachyon scalar field T with a Dirac- Born- Infeld type lagrangian and potential V (T) coupled to a canonically normalized scalar field with an arbitrary but factorizeable interaction potential B (T,phi) in the presence of a barotropic fluid. We will assume that the force between the barotropic fluid and the scalar fie

  44. Rui Dilão, Daniele Muraro

    We propose a new model describing the production and the establishment of the stable gradient of the Bicoid protein along the antero-posterior axis of the embryo of \textit{Drosophila}. In this model, we consider that \textit{bicoid} mRNA diffuses along the antero-posterior axis of the embryo and the protein is produced in the ribosomes localized near the sy

  45. T. Gopinath, Anil Kumar

    Liouville space search algorithm [Bruschweiler, Phys. Rev. Lett. {\bf 85}, 4815(2000).] utilizes mixed initial states of the ensemble, and has been successfully implemented earlier in weakly coupled spins, in which a spin can be identified as a qubit. It has recently been demonstrated that n-strongly coupled spins can be collectively treated as an n-qubit sy

  46. Michele Cignoni, Monica Tosi

    In this tutorial paper we summarize how the star formation (SF) history of a galactic region can be derived from the colour-magnitude diagram (CMD) of its resolved stars. The procedures to build synthetic CMDs and to exploit them to derive the SF histories (SFHs) are described, as well as the corresponding uncertainties. The SFHs of resolved dwarf galaxies o

  47. Radoslaw Szmytkowski, Sebastian Bielski

    Recently, Yakubovich [Opuscula Math. 26 (2006) 161--172] and Passian et al. [J. Math. Anal. Appl. doi:10.1016/j.jmaa.2009.06.067] have presented alternative proofs of an orthogonality relation obeyed by the Macdonald functions of imaginary order. In this note, we show that the validity of that relation may be also proved in a simpler way by applying a techni

  48. M. Crampin, T. Mestdag

    We demonstrate the usefulness of anholonomic frames in the contexts of nonholonomic and vakonomic systems. We take a consistently differential-geometric approach. As an application, we investigate the conditions under which the dynamics of the two systems will be consistent. A few illustrative examples confirm the results.

  49. A. Dorodnitsyn, T. Kallman

    We calculate a series of synthetic X-ray spectra from outflows originating from the obscuring torus in active galactic nuclei (AGN). Such modeling includes 2.5D hydrodynamical simulations of an X-ray excited torus wind, including the effects of X-ray heating, ionization, and radiation pressure. 3D radiation transfer calculations are performed in the 3D Sobol

  50. Alexander Yu. Kamenshchik, Chiara M. F. Mingarelli

    An exact solution of the Einstein equations for a Bianchi-I universe in the presence of dust, stiff matter and a negative cosmological constant, generalising the well-known Heckmann-Schucking solution is presented. This solution describes a universe existing during a finite period of cosmic time, where the beginning and the end of its evolution are character

  51. T. P. Downes, S. O&#39;Sullivan

    It is well known that non-ideal magnetohydrodynamic effects are important in the dynamics of molecular clouds: both ambipolar diffusion and possibly the Hall effect have been identified as significant. We present the results of a suite of simulations with a resolution of 512-cubed of turbulent decay in molecular clouds incorporating a simplified form of both

  52. Ljiljana Brankovic, Henning Fernau, Joachim Kneis, Dieter Kratsch Alexander Langer Mathieu Liedloff Daniel Raible Peter Rossmanith

    The lower and the upper irredundance numbers of a graph $G$, denoted $ir(G)$ and $IR(G)$ respectively, are conceptually linked to domination and independence numbers and have numerous relations to other graph parameters. It is a long-standing open question whether determining these numbers for a graph $G$ on $n$ vertices admits exact algorithms running in ti

  53. Olga Zamora, Carlos Abia, Bertrand Plez, Inmaculada Dominguez

    The aim of this work is to shed some light on the problem of the formation of carbon stars of R-type from a detailed study of their chemical composition. We use high-resolution and high signal-to-noise optical spectra of 23 R-type stars selected from the Hipparcos catalogue. The chemical analysis is made using spectral synthesis in LTE and state-of-the-art c

  54. Abhay Ashtekar, Miguel Campiglia, Adam Henderson

    Loop quantum cosmology (LQC) is used to provide concrete evidence in support of the general paradigm underlying spin foam models (SFMs). Specifically, it is shown that: i) the physical inner product in the timeless framework equals the transition amplitude in the deparameterized theory; ii) this quantity admits a %convergent vertex expansion a la SFMs in whi

  55. Olivier Cyr-Choinière, R. Daou, J. Chang, Francis Laliberté

    Recent studies of the high-Tc superconductor La_(1.6-x)Nd_(0.4)Sr_(x)CuO_(4) (Nd-LSCO) have found a linear-T in-plane resistivity rho_(ab) and a logarithmic temperature dependence of the thermopower S / T at a hole doping p = 0.24, and a Fermi-surface reconstruction just below p = 0.24 [1, 2]. These are typical signatures of a quantum critical point (QCP). H

  56. S. T. Millmore, I. Hawke

    We consider models of relativistic matter containing sharp interfaces across which the matter model changes. These models will be relevant for neutron stars with crusts, phase transitions, or for viscous boundaries where the length scale is too short to be modelled smoothly. In particular we look at numerical techniques that allow us to evolve stable interfa

  57. Ondrej Kilian, Guy Allan, Ludger Wirtz

    We present ab-initio phonon dispersion relations for the three lead chalcogenides PbS, PbSe, and PbTe. The acoustic branches are in very good agreement with inelastic neutron-scattering data and calculations of the specific heat give good agreement with experimental data. The pronounced minimum of the transverse optical branch at Gamma due to the near-ferroe

  58. Ronald Getoor

    During the three decades from 1930 to 1960 J. L. Doob was, with the possible exception of Kolmogorov, the man most responsible for the transformation of the study of probability to a mathematical discipline. His accomplishments were recognized by both probabilists and other mathematicians in that he is the only person ever elected to serve as president of bo

  59. Tobias Moroder, Otfried Gühne, Normand J. Beaudry, Marco Piani

    Many protocols and experiments in quantum information science are described in terms of simple measurements on qubits. However, in a real implementation, the exact description is more difficult, and more complicated observables are used. The question arises whether a claim of entanglement in the simplified description still holds, if the difference between t

  60. Alexandre C. M. Correia

    Some of the satellites in the Solar System, including the Moon, appear to have been captured from heliocentric orbits at some point in their past, and then have evolved to the present configurations. The exact process of how this trapping occurred is unknown, but the dissociation of a planetesimal binary in the gravitational field of the planet, gas drag, or

  61. U. Buchenau

    The fragility (the abnormally strong temperature dependence of the viscosity) of highly viscous liquids is shown to have two sources. The first is the temperature dependence of the barriers between inherent states considered earlier. The second is the recently discovered asymmetry between the actual inherent state and its neighbors. One needs both terms for

  62. A. Krimmel, A. Günther, W. Kraetschmer, H. Dekinger

    The transition--metal oxide CaCu$_3$Ru$_4$O$_{12}$ with perovskite--type structure shows characteristic properties of an intermediate--valence system. The temperature--dependent susceptibility exhibits a broad maximum around $150 - 160$ K. At this temperature, neutron powder diffraction reveals a small but significant volume change whereby the crystal struct

  63. Florentin Millour, Thomas Driebe, Olivier Chesneau, José Groh

    Most Wolf-Rayet stars (WR) of WC9 sub-type exhibit a dusty circumstellar envelope, but it is still a matter of debate how dust can form in their harsh environment. In a few cases, a pinwheel-like structure of the dusty envelope has been detected. Therefore, it has been suggested that dust formation in all dusty WR stars might be linked to colliding winds in

  64. Julien Kermorvant, Cornelis Jacominus Van Der Beek, Jean-Claude Mage, Bruno Marcilhac

    Using the dielectric resonator method, we have investigated nonlinearities in the surface impedance Zs = Rs + jXs of YBa2Cu3O7 thin films at 10 GHz as function of the incident microwave power level and temperature. The use of a rutile dielectric resonator allows us to measure the precise temperature of the films. We conclusively show that the usually observe

  65. Samantha Hickey, Andrew Bunker, Matt J. Jarvis, Kuenley Chiu

    We present the results of our search for high-redshift Lyman-break galaxies over the GOODS-South field. We use HST-ACS data in B, V, i&#39; & z&#39;, VLT-ISAAC J and Ks, Spitzer-IRAC 3.6, 4.5, 5.8 and 8.0 micron data in conjunction with the new HAWK-I Y-band science verification data to search for dropout galaxies in the redshift range 6<z<9. We survey ~119

  66. Young-Han Kim, Amos Lapidoth, Tsachy Weissman

    We study the best exponential decay in the blocklength of the probability of error that can be achieved in the transmission of a single bit over the Gaussian channel with an active noisy Gaussian feedback link. We impose an \emph{expected} block power constraint on the forward link and study both \emph{almost-sure} and \emph{expected} block power constraints

  67. S Santhosh Baboo, Nikhil Lobo

    In aerospace and defense, training is being carried out on the web by viewing PowerPoint presentations, manuals and videos that are limited in their ability to convey information to the technician. Interactive training in the form of 3D is a more cost effective approach compared to creation of physical simulations and mockups. This paper demonstrates how tra

  68. Tomas Brauner, Jin-yi Pang, Qun Wang

    Spin-one color superconductor is a viable candidate phase of dense matter in the interiors of compact stars. Its low-energy excitations will influence the transport properties of such matter and thus have impact on late-stage evolution of neutron stars. It also provides a good example of spontaneous symmetry breaking with rich breaking patterns. In this cont

  69. Aurelien Drezet

    In a old paper by G. Lochak, it is claimed that the Bell definition of a hidden variable is in conflict with the formalism of quantum mechanics. This result implies that it is not necessary to invoke non locality to explain the violation of the Bell inequality. A careful analysis of the concept of probability for hidden variables, as defined differently by B

  70. A. Odrzywolek

    Spherically symmetric, static model of the cosmological voids is constructed in the framework of the Tolman-Oppenheimer-Volkov equation with the cosmological constant. Extension of the Tooper result (dimensionless form of the TOV equation) is provided for non-zero $Λ$. Then, the equation is simplified in $α\to 0$, $λ\to 0$, $λ/α= const$ regime, suitable for

  71. G. Gligoric, A. Maluckov, L. Salasnich, B. Malomed

    The Bose-Einstein condensate (BEC), confined in a combination of the cigar-shaped trap and axial optical lattice, is studied in the framework of two models described by two versions of the one-dimensional (1D) discrete nonpolynomial Schrödinger equation (NPSE). Both models are derived from the three-dimensional Gross-Pitaevskii equation (3D GPE). To produce

  72. Sabah S. Al-Fedaghi, Bernhard Thalheim

    One of the most important aspects of security organization is to establish a framework to identify security significant points where policies and procedures are declared. The (information) security infrastructure comprises entities, processes, and technology. All are participants in handling information, which is the item that needs to be protected. Privacy

  73. Gregory Sivashinsky

    The Hamilton-Jacobi equation of relativistic quantum mechanics is revisited. The equation is shown to permit solutions in the form of breathers (oscillating/spinning solitons), displaying simultaneous particle-like and wave-like behaviour.

  74. G. Chirco, S. Liberati

    In arXiv:gr-qc/9504004 it was shown that the Einstein equation can be derived as a local constitutive equation for an equilibrium spacetime thermodynamics. More recently, in the attempt to extend the same approach to the case of $f(R)$ theories of gravity, it was found that a non-equilibrium setting is indeed required in order to fully describe both this the

  75. B. Ocana-Flaquer, S. Leon, D. Espada, S. Martin Ruiz

    Low $L_{FIR}$ Isolated Galaxies (IGs) from the AMIGA sample have low level of Star Formation (SF) activity. We observed the HCN(1-0) emission in a sample of IGs in order to test whether they follow the tight relation between $L_{HCN}$ and $L_{FIR}$ found for galaxies with more active SF.

  76. Lucia Canova, Jozef Strecka

    Ground-state and finite-temperature behaviour of the mixed spin-1/2 and spin-1 Ising-Heisenberg model on decorated planar lattices consisting of inter-connected diamonds is investigated by means of the generalised decoration-iteration mapping transformation. The obtained exact results clearly point out that this model has a rather complex ground state compos

  77. Gunter Malle, Gabriel Navarro

    We study blocks all of whose height zero ordinary characters have the same degree. We suspect that these might be the Broue-Puig nilpotent blocks.

  78. E Hassinger, D Aoki, F Bourdarot, G Knebel

    We describe here recent inelastic neutron scattering experiments on the heavy fermion compound URu2Si2 realized in order to clarify the nature of the hidden order (HO) phase which occurs below T_0 = 17.5 K at ambient pressure. The choice was to measure at a given pressure P where the system will go, by lowering the temperature, successively from paramagnetic

  79. N. Aharon, J. Silman

    We generalize the problem of coin flipping to more than two outcomes and parties. We term this problem dice rolling, and study both its weak and strong variants. We prove by construction that in quantum settings (i) weak N-sided dice rolling admits an arbitrarily small bias for any value of N, and (ii) two-party strong N-sided dice rolling saturates the corr

  80. V. V. Barmin, A. E. Asratyan, V. S. Borisov, C. Curceanu

    The data on the charge-exchange reaction K^+Xe --> K^0 p Xe, obtained with the bubble chamber DIANA, are reanalyzed using increased statistics and updated selections. Our previous evidence for formation of a narrow pK^0 resonance with mass near 1538 MeV is confirmed and reinforced. The statistical significance of the signal reaches some 8σ(6σ) when estimated

  81. Carlos E. Yaguna

    Neutralino dark matter can be indirectly detected by observing the gamma ray lines from the annihilation processes XX-->gg and XX-->gZ. In this paper we study the implications that the observation of these two lines could have for the determination of the supersymmetric parameter space. Within the minimal supergravity framework, we find that, independently o

  82. R. Pessoa, M. de Koning, S. A. Vitiello

    We address the issue of interaction between zero-point vacancies in solid 4He as described within the shadow wave-function model. Applying the reversible-work method and taking into account finite-size effects, we obtain a zero-point monovacancy concentration of (2.03 +- 0.02) 10^{-3}, which is slightly higher than the result due to Reatto et al. for the sam

  83. Bogdan Baishanski

    We present a new way of organizing the few mathematical statements which form introduction to Calculus: the epsilon-delta characterization of the limit is now d e r i v e d from four simple, intuitive and frequently used statements, which we choose as axioms.

  84. Tiangao Gou, Syed A. Jafar, Chenwei Wang

    We explore the degrees of freedom (DoF) of three classes of finite state compound wireless networks in this paper. First, we study the multiple-input single-output (MISO) finite state compound broadcast channel (BC) with arbitrary number of users and antennas at the transmitter. In prior work, Weingarten et. al. have found inner and outer bounds on the DoF w

  85. A. Bussmann-Holder, A. R. Bishop, A. Simon

    Nb doped SrTiO3, the first discovered two-gap superconductor, is shown to be the most unconventional one of the known multiband superconductors, since the smaller of the two superconducting gaps follows a non BCS temperature dependence. Such a behavior stems from two cooperating effects: an extreme anisotropy in the frequency dependent interactions, involvin

  86. H. O. Moser, L. K. Jian, H. S. Chen, M. Bahou

    Seeing sharper or becoming invisible are visions strongly driving the development of THz metamaterials. Strings are a preferred architecture of metamaterials as they extend continuously along one dimension. Here, we demonstrate that laterally interconnecting strings by structural elements that are placed in oscillation nodes such as to not quench electromagn

  87. Cz. Jasiukiewicz, T. Paszkiewicz, S. Wolski

    Young&#39;s and shear moduli and Poisson&#39;s ratio of polycrystalline solids consisting of 2D quadratic and 3D cubic randomly oriented grains of the same size and shape is studied. Considered polycrystals are initially unstrained. It is shown that for such polycrystals the division of the mechanical stability regions into areas of various auxeticity proper

  88. Weijiang Gong, Xuefeng Xie, Yu Han, Guozhu Wei

    Electron transport through a three-electrode triple-quantum-dot ring with the source electrode of spin-dependent splitting of chemical potentials (spin bias) is theoretically investigated. We find clear charge and spin currents in the drain electrodes driven by the spin bias, despite the absence of charge bias between the source and drain electrodes, and the

  89. Edgars Bervalds

    The Phi- relationship also known as Phi-factor appears in a number of lattice structures, mostly considering the lines within several separate circles or polygons. The paper considers a regular hexagonal tessellation as a lattice with the highest specific mechanical stiffness.

  90. M. Rafiee, S. Jalali Asadabadi

    The Pb/Si(111) thin films were simulated within the density functional theory (DFT). The well-known Perdew-Burke-Ernzerhof (PBE) version of the generalized gradient approximation (GGA) and its recent nonempirical successor Wu-Cohen (WC) issue were used to estimate the exchange-correlation functional. Lattice parameters were calculated for Bulk of the Pb and

  91. V. K. Konyukhov

    Spin degrees of freedom of water molecule in gas and liquid state were investigated in order to provide a reasonable answer about the unsolved problem of a long-term behavior of water spin isomers. The approach used involves an assumption that molecules change their spin state from a pure state to a mixed one when they interact with some sorts of adsorbent s

  92. J. Plata

    The effect of a sinusoidal modulation of the interaction strength on a fermion-pair condensate is analytically studied. The system is described by a generalization of the coupled fermion-boson model that incorporates a time-dependent intermode coupling induced via a magnetic Feshbach resonance. Nontrivial effects are shown to emerge depending on the relative

  93. Franziska Piontek, Matthias Steinmetz

    We present a systematic study of stellar feedback processes in simulations of disk galaxy formation. Using a dark matter halo with properties similar to the ones for the Milky Way&#39;s stellar halo, we perform a comparison of different methods of distributing energy related to feedback processes to the surrounding gas. A most promising standard model is app

  94. Teiko Heinosaari, Juha-Pekka Pellonpää

    We show that the canonical phase measurement is pure in the sense that the corresponding positive operator valued measure (POVM) is extremal in the convex set of all POVMs. This means that the canonical phase measurement cannot be interpreted as a noisy measurement, even if it is not a projection valued measure.

  95. A. Caccianiga, P. Severgnini, R. Della Ceca, A. Corral

    We have studied the relationship between the AGN radio-loudness and the mass of the central black-hole by using the ~190 type 1 AGN selected in the XMM-Newton Bright Survey (XBS). We find that radio-loud AGNs are much more frequent at high black-hole masses being a factor ~10 times more common for masses >10^9 Msun when compared to masses between 10^7-10^9 M

  96. Didier Fraix-Burnet

    The Hubble tuning fork diagram, based on morphology and established in the 1930s, has always been the preferred scheme for classification of galaxies. However, the current large amount of multiwavelength data, most often spectra, for objects up to very high distances, asks for more sophisticated statistical approaches. Interpreting formation and evolution of

  97. Dan Hooper, Kathryn M. Zurek

    PAMELA&#39;s observation that the cosmic ray positron fraction increases rapidly with energy implies the presence of primary sources of energetic electron-positron pairs. Of particular interest is the possibility that dark matter annihilations in the halo of the Milky Way provide this anomalous flux of antimatter. The recent measurement of the cosmic ray ele

  98. Asis Kumar Chattopadhyay, Tanuka Chattopadhyay, Emmanuel Davoust, Saptarshi Mondal

    An objective classification of the globular clusters of NGC 5128 has been carried out by using a model-based approach of cluster analysis. The set of observable parameters includes structural parameters, spectroscopically determined Lick indices and radial velocities from the literature. The optimum set of parameters for this type of analysis is selected thr

  99. J. S. Clark, P. A. Crowther, V. M. Larionov, I. A. Steele

    We characterise the variability in the physical properties of the luminous blue variable AFGL2298 between 1989-2008. In conjunction with published data from 1989-2001, we have undertaken a long term (2001-2008) near-IR spectroscopic and photometric observational campaign for this star and utilise a non-LTE model atmosphere code to interpret these data. We fi

  100. Thierry Rabilloud, Ali R Vaezzadeh, Noelle Potier, Cécile Lelong

    Proteomics can be defined as the large-scale analysis of proteins. Due to the complexity of biological systems, it is required to concatenate various separation techniques prior to mass spectrometry. These techniques, dealing with proteins or peptides, can rely on chromatography or electrophoresis. In this review, the electrophoretic techniques are under scr