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June 2009 arXiv papers — page 40

Showing 3,9014,000 of 5,471 papers

  1. R. E. Kastner

    Cramer's Transactional Interpretation (TI) is applied to the "Quantum Liar Experiment" (QLE). It is shown how some apparently paradoxical features can be explained naturally, albeit nonlocally (since TI is an explicitly nonlocal interpretation, at least from the vantage point of ordinary spacetime). At the same time, it is proposed that in order

  2. Jacob S. Christiansen, Barry Simon, Maxim Zinchenko

    Let $\fre\subset\bbR$ be a finite union of disjoint closed intervals. We study measures whose essential support is $\fre$ and whose discrete eigenvalues obey a 1/2-power condition. We show that a Szeg\H{o} condition is equivalent to \[ \limsup \f{a_1... a_n}{\ca(\fre)^n}>0 \] (this includes prior results of Widom and Peherstorfer--Yuditskii). Using Remling's

  3. Megumi Harada, Gregory D. Landweber, Reyer Sjamaar

    Let $X$ be a topological space and $G$ a compact connected Lie group acting on $X$. Atiyah proved that the $G$-equivariant K-group of $X$ is a direct summand of the $T$-equivariant K-group of $X$, where $T$ is a maximal torus of $G$. We show that this direct summand is equal to the subgroup of $K_T^*(X)$ annihilated by certain divided difference operators. I

  4. T. Amemiya, M. Yano, K. Morita, I. Umegaki

    We report the crystal structure and unconventional magnetic ordering of Cs_2Cu_3CeF_{12}, which is composed of buckled kagome lattice of Cu^{2+} ions. The exchange network in the buckled kagome lattice is fairly anisotropic, so that the present spin system can be divided into two subsystems: alternating Heisenberg chains with strong antiferromagnetic exchang

  5. Qi Zhang, Jiangbin Gong, C. H. Oh

    Tripod-scheme cold atoms interacting with laser beams have attracted considerable interest for their role in synthesizing effective non-Abelian vector potentials. Such effective vector potentials can be exploited to realize an all-optical imprinting of geometric phases onto matter waves. By working on carefully designed extensions of our previous work, we sh

  6. S. Broadfoot, U. Dorner, D. Jaksch

    We develop a concept of entanglement percolation for long-distance singlet generation in quantum networks with neighboring nodes connected by partially entangled bipartite mixed states. We give a necessary and sufficient condition on the class of mixed network states for the generation of singlets. States beyond this class are insufficient for entanglement p

  7. Amy N. Nicholson

    The study of nuclear physics using lattice QCD is hindered by an exponentially large signal-to-noise problem which is conventionally alleviated by raising the quark masses to unphysically high values. We propose a novel form of partial quenching for calculations involving nucleons in which the sea quark masses are taken to be smaller than the valence quark m

  8. James Braun, Daan Hubert

    A well-known potential dark matter signature is emission of GeV - TeV neutrinos from annihilation of neutralinos gravitationally bound to massive objects. We present results from recent searches for high energy neutrino emission from the Sun with AMANDA, in all cases revealing no significant excess. We show limits on both neutralino-induced muon flux from th

  9. Arian Kriesch

    This work reports on the experimental investigation of surface plasmon polaritons (SPP) on cylindrical wires of small diameters. Applying a new technique that was developed by this group and recently reported, single wire and wire array samples of gold (Au) and silver (Ag) with small diameters 400nm < D < 3 mum and high aspect ratios <= 75000 in photonic cry

  10. Oleksandr Zelyak, Ganpathy Murthy

    We study a system of two tunnel-coupled quantum dots, with the first dot containing interacting electrons (described by the Universal Hamiltonian) not subject to spin-orbit coupling, whereas the second contains non-interacting electrons subject to spin-orbit coupling. We focus on describing the behavior of the system near the Stoner transition. Close to the

  11. Ashish Khisti, Suhas Diggavi, Gregory Wornell

    We study the problem of generating a shared secret key between two terminals in a joint source-channel setup -- the sender communicates to the receiver over a discrete memoryless wiretap channel and additionally the terminals have access to correlated discrete memoryless source sequences. We establish lower and upper bounds on the secret-key capacity. These

  12. Ian M. Shoemaker

    Gauge-mediated models of supersymmetry-breaking imply that stable Q-balls can form in the early universe and act as dark matter. All stable Q-balls in the MSSM are associated with one or more flat directions. We show that while Q-balls are produced from the fragmentation of a flat direction condensate, they quickly evolve to a ground state that is slightly a

  13. Christopher Voll

    These notes grew out of lectures given at the LMS-EPSRC Short Course on Asymptotic Methods in Infinite Group Theory, University of Oxford, 9-14 September 2007, organised by Dan Segal.

  14. Xiaoting Wang, S. G. Schirmer

    We show how to apply Lyapunov control design to the problem of entanglement creation between two atoms in distant cavities connected by optical fibers. The Lyapunov control design is optimal in the sense that the distance from the target state decreases monotonically and exponentially, and the concurrence increases accordingly. This method is far more robust

  15. Jeremy Sain

    Over the last 25 years, the notion of &#34;fuzzy spaces&#34; has become ubiquitous in the high-energy physics literature. These are finite dimensional noncommutative approximations of the algebra of functions on a classical space. The most well known examples come from the Berezin quantization of coadjoint orbits of compact semisimple Lie groups. We develop

  16. Georgios T. Kossioris, Georgios E. Zouraris

    We consider an initial- and Dirichlet boundary- value problem for a fourth-order linear stochastic parabolic equation, in two or three space dimensions, forced by an additive space-time white noise. Discretizing the space-time white noise a modeling error is introduced and a regularized fourth-order linear stochastic parabolic problem is obtained. Fully-disc

  17. Alexander Borichev, Vesselin Petkov

    We study functions f(z) holomorphic in the upper half plane and having no zeros when the imaginary part of z is between 0 and 1, and we obtain a lower bound for the modulus of f(z) in this strip. In our analysis we deal with scalar functions f(z) as well as with operator valued holomorphic functions I+A(z) assuming that A(z) is a trace class operator in the

  18. Erik Carlsson

    The Nekrasov partition function in supersymmetric quantum gauge theory is mathematically formulated as an equivariant integral over certain moduli spaces of sheaves on a complex surface. In ``Seiberg-Witten Theory and Random Partitions&#39;&#39;, Nekrasov and Okounkov studied these integrals using the representation theory of ``vertex operators&#39;&#39; and

  19. N. Seymour, M. Huynh, T. Dwelly, M. Symeonidis

    In order to examine the far-IR/radio correlation at high redshift we have studied the Spitzer 70um/far-infrared (far-IR) properties of sub-mJy radio sources from the 13^H XMM-Newton/Chandra Deep Field by redshift and galaxy type: active galactic nucleus (AGN) or star forming galaxy (SFG). We directly detect 70um counterparts (at >3sigma significance) for 22.

  20. Tim Dokchitser, Vladimir Dokchitser

    The purpose of the paper is to complete several global and local results concerning parity of ranks of elliptic curves. Primarily, we show that the Shafarevich-Tate conjecture implies the parity conjecture for all elliptic curves over number fields, give a formula for local and global root numbers of elliptic curves and complete the proof of a conjecture of

  21. Martin Renqiang Min, David A. Stanley, Zineng Yuan, Anthony Bonner

    KNN is one of the most popular classification methods, but it often fails to work well with inappropriate choice of distance metric or due to the presence of numerous class-irrelevant features. Linear feature transformation methods have been widely applied to extract class-relevant information to improve kNN classification, which is very limited in many appl

  22. Claudia Greco, Gisella Clementini, Marcio Catelan, Enrico V. Held

    We present a new study of the variable star population in globular cluster 5 of the Fornax dwarf spheroidal galaxy, based on B and V time series photometry obtained with the MagIC camera of the 6.5 m Magellan Clay telescope and complementary HST archive data. Light curves and accurate periodicities were obtained for 30 RR Lyrae stars and 1 SX Phoenicis varia

  23. B. Meneux, L. Guzzo, S. de la Torre, C. Porciani

    We study the dependence of galaxy clustering on luminosity and stellar mass at redshifts z ~ [0.2-1] using the first zCOSMOS 10K sample. We measure the redshift-space correlation functions xi(rp,pi) and its projection wp(rp) for sub-samples covering different luminosity, mass and redshift ranges. We quantify in detail the observational selection biases and w

  24. Nestor E. Massa, Juliano C. Denardin, Leandro M. Socolovsky, Marcelo Knobel

    We report on near normal infrared reflectivity spectra of ~550 nm thick films made of cosputtered transition metal nanograins and SiO2 in a wide range of metal fractions. Co0.85(SiO2)0.15,with conductivity well above the percolation threshold has a frequency and temperature behavior according to what it is find in conducting metal oxides. The electron scatte

  25. A. Niedzielski, G. Nowak, M. Adamów, A. Wolszczan

    We present the discovery of substellar-mass companions to three stars by the ongoing Penn State - Toru\&#39; n Planet Search (PTPS) conducted with the 9.2-m Hobby-Eberly Telescope. The K2-dwarf, BD +14 4559, has a 1.5 M$_{J}$ companion with the orbital period of 269 days and shows a non-linear, long-term radial velocity trend, which indicates a possible pres

  26. Tilman Plehn, Michael Rauch, Michael Spannowsky

    Top plus jets production at hadron collider allows us to study the couplings of the top quark. In the Standard Model, two single top processes contribute to the top-jets final state. Beyond the Standard Model, additional direct top production can occur. All three processes probe top gauge couplings including flavor mixing. The structure of accompanying QCD j

  27. M. Bonnefoy, G. Chauvin, C. Dumas, A-M. Lagrange

    Tight binaries discovered in young, nearby associations, with known distances, are ideal targets to provide dynamical mass measurements to test the physics of evolutionary models at young ages and very low masses. We report for the first time the binarity of TWA22, possible new dynamical calibrator for evolutionary models at young ages. Based on an accurate

  28. Davod Khojasteh Salkuyeh

    In [7], a new iterative method for solving linear system of equations was presented which can be considered as a modification of the Gauss-Seidel method. Then in [4] a different approach, say 2D-DSPM, and more effective one was introduced. In this paper, we improve this method and give a generalization of it. Convergence properties of this kind of generaliza

  29. Michael Greenblatt

    For a small disk D centered at the origin in R^2, a smooth real-valued function S(x,y) on D, and a positive epsilon, we consider the measure of the points in D where |S(x,y)| < epsilon, as well as oscillatory integral analogues. Specifically, we consider the effect of perturbing S(x,y) on these quantities. Besides being of intrinsic interest, these questions

  30. Irene I. Bouw, Brian Osserman

    In this paper, we compute the number of covers of curves with given branch behavior in characteristic p for one class of examples with four branch points and degree p. Our techniques involve related computations in the case of three branch points, and allow us to conclude in many cases that for a particular choice of degeneration, all the covers we consider

  31. Cyril Petitjean, Daniel Waltner, Jack Kuipers, Inanc Adagideli

    We address frequency-dependent quantum transport through mesoscopic conductors in the semiclassical limit. By generalizing the trajectory-based semiclassical theory of dc quantum transport to the ac case, we derive the average screened conductance as well as ac weak-localization corrections for chaotic conductors. Thereby we confirm respective random matrix

  32. J. W. den Herder, A. Boyarsky, O. Ruchayskiy, K. Abazajian

    We propose an X-ray mission called Xenia to search for decaying superweakly interacting Dark Matter particles (super-WIMP) with a mass in the keV range. The mission and its observation plan are capable of providing a major break through in our understanding of the nature of Dark Matter (DM). It will confirm, or reject, predictions of a number of particle phy

  33. Y. R. Fernandez, D. Jewitt, J. E. Ziffer

    We present thermal observations of 44 Jovian Trojan asteroids with diameters (D) ranging from 5 to 24 km. All objects were observed at a wavelength of 24 microns with the Spitzer Space Telescope. Measurements of the thermal emission and of scattered optical light, mostly from the University of Hawaii 2.2-meter telescope, together allow us to constrain the di

  34. Rory Barnes, Brian Jackson, Richard Greenberg, Sean N. Raymond

    The habitable zones of main sequence stars have traditionally been defined as the range of orbits that intercept the appropriate amount of stellar flux to permit surface water on a planet. Terrestrial exoplanets discovered to orbit M stars in these zones, which are close-in due to decreased stellar luminosity, may also undergo significant tidal heating. Tida

  35. Seth Sullivant

    We show that the marginal semigroup of a binary graph model is normal if and only if the graph is free of K_4 minors. The technique, based on the interplay of normality and the geometry of the marginal cone, has potential applications to other normality questions in algebraic statistics.

  36. T. V. Zaqarashvili, R. Erdelyi

    Since their discovery, spicules have attracted increased attention as energy/mass bridges between the dense and dynamic photosphere and the tenuous hot solar corona. Mechanical energy of photospheric random and coherent motions can be guided by magnetic field lines, spanning from the interior to the upper parts of the solar atmosphere, in the form of waves a

  37. Joseph Najnudel, Ashkan Nikeghbali

    In this paper, we associate, to any submartingale of class $(Σ)$, defined on a filtered probability space $(Ω, \mathcal{F}, \mathbb{P}, (\mathcal{F}_t)_{t \geq 0})$, which satisfies some technical conditions, a $σ$-finite measure $\mathcal{Q}$ on $(Ω, \mathcal{F})$, such that for all $t \geq 0$, and for all events $Λ_t \in \mathcal{F}_t$: $$ \mathcal{Q} [Λ_t

  38. J. Marciak-Kozlowska, M. Pelc, M. A. Kozlowski

    Fascinating developments in optical pulse engineering over the last 20 years lead to the generation of laser pulses as short as few femtosecond, providing a unique tool for high resolution time domain spectroscopy. However, a number of the processes in nature evolve with characteristic times of the order of 1 fs or even shorter. Time domain studies of such p

  39. Stuart A. Rankin

    In 1962, R. C. Lyndon and M. P. Shutzenberger established that for any positive integers r and s, any sequence of length at least r+s that is both r-periodic and s-periodic is then (r,s)-periodic. Shortly thereafter (1965), N. J. Fine and H. S. Wilf proved that for any positive integers r and s, if a is an infinite seqeunce of period r and b is an infinite s

  40. A. P. Milone, P. B. Stetson, G. Piotto, L. R. Bedin

    We have analyzed ACS/WFC and WFPC2 images from HST, as well as ground-based data to study the radial distribution of the double sub-giant branch (SGB) recently discovered in the Galactic globular cluster NGC 1851. We found that the SGB split can be followed all the way from the cluster center out to at least 8\arcmin from the center. Beyond this distance out

  41. Andrey Breslav

    Here we present a work aimed on efficiently creating textual language dialects and supporting tools for them (e.g. compiler front-ends, IDE support, pretty-printers, etc.). A dialect is a language which may be described with a (relatively small) set of changes to some other language (a parent language). For example we can consider SQL dialects used in DB-man

  42. N. -C. Yeh, A. D. Beyer, M. L. Teague, S. -P. Lee

    The low-energy excitations of cuprate superconductors exhibit various characteristics that differ from those of simple Bogoliubov quasiparticles for pure d_{x^2-y^2}-wave superconductors. Here we report experimental studies of spatially resolved quasiparticle tunnelling spectra of hole- and electron-type cuprate superconductors that manifest direct evidences

  43. Rodolfo Gambini, Jorge Pullin, Saeed Rastgoo

    We study gravity coupled to a scalar field in spherical symmetry using loop quantum gravity techniques. Since this model has local degrees of freedom, one has to face ``the problem of dynamics&#39;&#39;, that is, diffeomorphism and Hamiltonian constraints that do not form a Lie algebra. We tackle the problem using the ``uniform discretization&#39;&#39; techn

  44. C. W. Ormel, D. Paszun, C. Dominik, A. G. G. M. Tielens

    In dense molecular clouds collisions between dust grains alter the ISM-dust size distribution. We study this process by inserting the results from detailed numerical simulations of two colliding dust aggregates into a coagulation model that computes the dust size distribution with time. All collisional outcomes -- sticking, fragmentation (shattering, breakag

  45. Thibault Damour, Alessandro Nagar

    The Effective One Body (EOB) formalism is an analytical approach which aims at providing an accurate description of the motion and radiation of coalescing binary black holes with arbitrary mass ratio. We review the basic elements of this formalism and discuss its aptitude at providing accurate template waveforms to be used for gravitational wave data analysi

  46. B. M. Peden, D. Meiser, M. L. Chiofalo, M. J. Holland

    We describe a scheme for probing a gas of ultracold atoms trapped in an optical lattice and moving in the presence of an external potential. The probe is non-destructive and uses the existing lattice fields as the measurement device. Two counter-propagating cavity fields simultaneously set up a conservative lattice potential and a weak quantum probe of the a

  47. Mariela Vieytes, Pablo Mauas, Rodrigo Diaz

    We study the differences in chromospheric structure induced in K stars by stellar activity, to expand our previous work for G stars, including the Sun as a star. We selected six stars of spectral type K with 0.82$<B-V<$0.90, including the widely studied Epsilon Eridani and a variety of magnetic activity levels. We computed chromospheric models for the stars

  48. Alexander Herzog, Peter Horsch, Andrzej M. Oles, Jesko Sirker

    We describe a Peierls dimerization which occurs in ferromagnetic spin chains at finite temperature, within the modified spin-wave theory. Usual spin-wave theory is modified by introducing a Lagrange multiplier which enforces a nonmagnetic state at finite temperature. It is shown that this method gives results in excellent agreement with the density--matrix r

  49. P. Garaud, L. Acevedo-Arreguin

    The solar convection zone exhibits a strong level of differential rotation, whereby the rotation period of the polar regions is about 25-30% longer than the equatorial regions. The Coriolis force associated with these zonal flows perpetually &#34;pumps&#34; the convection zone fluid, and maintains a quasi-steady circulation, poleward near the surface. What i

  50. Henri M. J. Boffin

    With the availability of nice images and amazing, dramatic stories, the fundamental questions it addresses, and the attraction is exerces on many, it is often assumed that astronomy is an obvious topic for the media. Looking more carefully, however, one realises that the truth is perhaps not as glamorous as one would hope, and that, although well present in

  51. Kai-Cheng Zhang, Bang-Gui Liu

    We investigate the exchange bias and training effects in the FM/AF heterostructures using a unified Monte Carlo dynamical approach. This real dynamical method has been proved reliable and effective in simulating dynamical magnetization of nanoscale magnetic systems. The magnetization of the uncompensated AF layer is still open after the first field cycling i

  52. Julien Derr, Jason T. Hopper, Anirban Sain, Andrew D. Rutenberg

    We model the self-organization of the MinE ring that is observed during subcellular oscillations of the proteins MinD and MinE within the rod-shaped bacterium {\it Escherichia coli}. With a steady-state approximation, we can study the MinE-ring generically -- apart from the other details of the Min oscillation. Rebinding of MinE to depolymerizing MinD filame

  53. C. Gold, L. Peyker, E. -W. Scheidt, H. Michor

    We investigate the novel intermetallic ternary compounds \emph{R}Co$_{9}$Ge$_{4}$ with \emph{R} = La and Ce by means of $X$-ray diffraction, susceptibility and specific heat measurements. CeCo$_{9}$Ge$_{4}$ crystallizes in the space group ${I}$ 4/ ${mcm}$ and is characterized by the coexistence of two different magnetic sublattices. The Ce-based sublattice,

  54. V. G. Bardakov, R. Mikhailov, V. V. Vershinin, J. Wu

    In this article, we investigate various properties of the pure virtual braid group PV_3. From its canonical presentation, we obtain a free product decomposition of PV_3. As a consequence, we show that PV_3 is residually torsion free nilpotent, which implies that the set of finite type invariants in the sense of Goussarov-Polyak-Viro is complete for virtual p

  55. L Peyker, C Gold, E-W Scheidt, H Michor

    Starting with the heavy fermion compound CeNi$_9$Ge$_4$, the substitution of nickel by copper leads to a dominance of the RKKY interaction in competition with the Kondo and crystal field interaction. Consequently, this results in an antiferromagnetic phase transition in CeNi$_{9-x}$Cu$_x$Ge$_4$ for $x>0.4$, which is, however, not fully completed up to a Cu-c

  56. A. Cisek, W. Schäfer, A. Szczurek

    We extend the k_\perp-factorization formalism for exclusive photoproduction of vector mesons to the production of electroweak Z^0 bosons. Predictions for the gamma p \to Z^0 p and p p \to p p Z^0 reactions are given using an unintegrated gluon distribution tested against deep inelastic data. We present distributions in the Z^0 rapidity, transverse momentum o

  57. A. F. Lanza

    Evidence of magnetic interaction between late-type stars and close-in giant planets is provided by the observations of stellar hot spots rotating synchronously with the planets and showing an enhancement of chromospheric and X-ray fluxes. We investigate star-planet interaction in the framework of a magnetic field model of a stellar corona, considering the in

  58. G. P. Korchemsky, E. Sokatchev

    In addition to the superconformal symmetry of the underlying Lagrangian, the scattering amplitudes in planar N=4 super-Yang-Mills theory exhibit a new, dual superconformal symmetry. We address the question of how powerful these symmetries are to completely determine the scattering amplitudes. We use the example of the NMHV superamplitudes to show that the co

  59. F. Michler, B. Schenke, C. Greiner

    We use the real-time Keldysh formalism to investigate finite lifetime effects on the photon emission from a quark-gluon plasma (QGP). We provide an ansatz which eliminates the divergent contribution from the vacuum polarization and renders the photon spectrum UV-finite if the time evolution of the QGP is described in a suitable manner.

  60. G. Sardanashvily

    The fact that the conserved current of a gauge symmetry is reduced to a superpotential is proved in a very general setting.

  61. O. P. Zhelenkova, A. I. Kopylov

    We report the results of optical identification of a sample of RC catalog radio sources with the FIRST and SDSS surveys. For 320 sources identified with NVSS and FIRST objects we perform optical identification with the SDSS survey. When selecting optical candidates we make maximum use of the information about the structure of radio sources as provided by the

  62. R. E. Angulo, S. D. M. White

    We use the Extended-Press-Schechter (EPS) formalism to study halo assembly histories in a standard $Λ$CDM cosmology. A large ensemble of Monte Carlo random walks provides the {\it entire} halo membership histories of a representative set of dark matter particles, which we assume to be neutralinos. The first generation halos of most particles do not have a ma

  63. F. Mantovani, K. -H. Mack, F. M. Montenegro-Montes, A. Rossetti

    We completed observations with the Effelsberg 100-m radio telescope to measure the polarised emission from a complete sample of Compact Steep-Spectrum sources. We observed the sources at four different frequencies. We complemented these measurements with polarisation parameters at 1.4 GHz derived from the NVSS. Previous single dish measurements were taken fr

  64. M. A. Rajabpour

    Different aspects of the connection between the Bessel process and the conformal quantum mechanics (CQM) are discussed. The meaning of the possible generalizations of both models is investigated with respect to the other model, including self adjoint extension of the CQM. Some other generalizations such as the Bessel process in the wide sense and radial Orns

  65. Xicheng Zhang

    In this paper we first prove a Clark--Ocone formula for any bounded measurable functional on Poisson space. Then using this formula, under some conditions on the intensity measure of Poisson random measure, we prove a variational representation formula for the Laplace transform of bounded Poisson functionals, which has been conjectured by Dupuis and Ellis [A

  66. Tyler J. VanderWeele, James M. Robins

    Notions of minimal sufficient causation are incorporated within the directed acyclic graph causal framework. Doing so allows for the graphical representation of sufficient causes and minimal sufficient causes on causal directed acyclic graphs while maintaining all of the properties of causal directed acyclic graphs. This in turn provides a clear theoretical

  67. C. Schuck, F. Rohde, N. Piro, M. Almendros

    We observe the interaction of a single trapped calcium ion with single photons produced by a narrow-band, resonant down-conversion source [A. Haase et al., Opt. Lett. 34, 55 (2009)], employing a quantum jump scheme. Using the temperature dependence of the down-conversion spectrum and the tunability of the narrow source, absorption of the down-conversion phot

  68. C. Richardt, G. Anton, K. Graf, J. Hoessl

    This article focuses on techniques for acoustic noise reduction, signal filters and source reconstruction. For noise reduction, bandpass filters and cross correlations are found to be efficient and fast ways to improve the signal to noise ratio and identify a possible neutrino-induced acoustic signal. The reconstruction of the position of an acoustic point s

  69. Gabriela Guevara-Carrion, Carlos Nieto-Draghi, Jadran Vrabec, Hans Hasse

    Transport properties of liquid methanol and ethanol are predicted by molecular dynamics simulation. The molecular models for the alcohols are rigid, non-polarizable and of united-atom type. They were developed in preceding work using experimental vapor-liquid equilibrium data only. Self- and Maxwell-Stefan diffusion coefficients as well as the shear viscosit

  70. Christopher A. Fuchs, Ruediger Schack

    In quantum Bayesian inference problems, any conclusions drawn from a finite number of measurements depend not only on the outcomes of the measurements but also on a prior. Here we show that, in general, the prior remains important even in the limit of an infinite number of measurements. We illustrate this point with several examples where two priors lead to

  71. Marcus Hutter

    General-purpose, intelligent, learning agents cycle through sequences of observations, actions, and rewards that are complex, uncertain, unknown, and non-Markovian. On the other hand, reinforcement learning is well-developed for small finite state Markov decision processes (MDPs). Up to now, extracting the right state representations out of bare observations

  72. Vladimir Dogiel, Dmitrii Chernyshov, Takayuki Yuasa, Kwong-Sang Cheng

    We showed that if the non-thermal emission from the Galactic center in the range 14-40 keV is due to inverse bremsstrahlung emission of subrelativistic protons, their interactions with hot and cold fractions of the interstellar medium are equally important. Our estimation show that about 30% of the total non-thermal flux from the GC in the range 14-40 keV is

  73. Gabriela Ciuperca

    The paper considers two-phase random design linear regression models. The errors and the regressors are stationary long-range dependent Gaussian. The regression parameters, the scale parameters and the change-point are estimated using a method introduced by Rousseeuw and Yohai(1984). This is called S-estimator and it has the property that is more robust than

  74. G. A. Fernandez, J. Vrabec, H. Hasse

    Shear and bulk viscosity and thermal conductivity for argon, krypton, xenon, and methane and the binary mixtures argon+krypton and argon+methane were determined by equilibrium molecular dynamics with the Green-Kubo method. The fluids were modeled by spherical Lennard-Jones pair-potentials with parameters adjusted to experimental vapor liquid-equilibria data

  75. Adrian Stan, Nils Erik Dahlen, Robert van Leeuwen

    We perform $GW$ calculations on atoms and diatomic molecules at different levels of self-consistency and investigate the effects of self-consistency on total energies, ionization potentials and on particle number conservation. We further propose a partially self-consistent $GW$ scheme in which we keep the correlation part of the self-energy fixed within the

  76. Tomasz Srokowski

    The Lévy, jumping process, defined in terms of the jumping size distribution and the waiting time distribution, is considered. The jumping rate depends on the process value. The fractional diffusion equation, which contains the variable diffusion coefficient, is solved in the diffusion limit. That solution resolves itself to the stretched Gaussian when the o

  77. Adrian Stan, Nils Erik Dahlen, Robert van Leeuwen

    We have developed a time propagation scheme for the Kadanoff-Baym equations for general inhomogeneous systems. These equations describe the time evolution of the nonequilibrium Green function for interacting many-body systems in the presence of time-dependent external fields. The external fields are treated nonperturbatively whereas the many-body interaction

  78. Antoinette Tordesillas, Edward Lam, Philip T. Metzger

    The hyperstatic nature of granular packings of perfectly rigid disks is analyzed algebraically and through numerical simulation. The elementary loops of grains emerge as a fundamental element in addressing hyperstaticity. Loops consisting of an odd number of grains behave differently than those with an even number. For odd loops, the latent stresses are exte

  79. Cristopher Moore, Alexander Russell

    Celebrated work of Jerrum, Sinclair, and Vigoda has established that the permanent of a {0,1} matrix can be approximated in randomized polynomial time by using a rapidly mixing Markov chain. A separate strand of the literature has pursued the possibility of an alternate, purely algebraic, polynomial-time approximation scheme. These schemes work by replacing

  80. L. Magaud, F. Hiebel, F. Varchon, P. Mallet

    Graphene, the two-dimensional form of carbon presents outstanding electronic and transport properties. This gives hope for the development of applications in nanoelectronics. However, for industrial purpose, graphene has to be supported by a substrate. We focus here on the graphene-on-SiC system to discuss how the SiC substrate interacts with the graphene la

  81. K. Carva, D. Legut, P. M. Oppeneer

    In pump-probe experiments an intensive laser pulse creates non-equilibrium excited electron distributions in the first few hundred femtoseconds after the pulse. The influence of non-equilibrium electron distributions caused by a pump laser on the apparent X-ray magnetic circular dichroism (XMCD) signal of Ni is investigated theoretically here for the first t

  82. Vladimir Spokoiny

    This paper offers a new approach to modeling and forecasting of nonstationary time series with applications to volatility modeling for financial data. The approach is based on the assumption of local homogeneity: for every time point, there exists a historical interval of homogeneity, in which the volatility parameter can be well approximated by a constant.

  83. Amalendu Krishna

    The goal of this paper is to prove the Riemann-Roch isomorphism for the higher equivariant K-theory of varieties with action of a linear algebraic group.

  84. Olga Aryasova, Andrey Pilipenko

    We consider two depending Wiener processes which have membranes at zero with different permeability coefficients. Starting from different points, the processes almost surely do not meet at any fixed point except that where membranes are situated. The necessary and sufficient conditions for the meeting of the processes are found. It is shown that the probabil

  85. Nikolaj Glazunov

    I discuss (ontologies_and_ontological_knowledge_bases / formal_methods_and_theories) duality and its category theory extensions as a step toward a solution to Knowledge-Based Systems Theory. In particular I focus on the example of the design of elements of ontologies and ontological knowledge bases of next three electronic courses: Foundations of Research Ac

  86. Christian Pierre

    All kinds of global correspondences of Langlands are evaluated from the functional representation spaces of the algebraic bilinear semigroups GL2(.x.) with entries in products,right by left,of sets of archimedean increasing completions. Degenerate singularities on these functional representation spaces can give rise,by versal deformations and blowups of thes

  87. Oleg A. Teplov

    The mass formation of basic vector mesons up to energy 3.8 GeV was studied. The investigation was done with using of jet mechanism, the harmonic quarks and neutral colorless groups. The stage of a whole string with a zero interquark momentum was considered as a separate stage of hadronization. The quark group with rest mass equal to experimental mass of hadr

  88. Sandro Mereghetti, Nicola La Palombara

    The X-ray pulsar SAX J0635+0533 was repeatedly observed with the XMM-Newton satellite in 2003-2004. The precise localization provided by these observations confirms the association of SAX J0635+0533 with a Be star. The source was found, for the first time, in a low intensity state, a factor ~30 lower than that seen in all previous observations. The spectrum,

  89. E. G. Bessonov

    In this review a history of development of electron accelerators for HEP and for LSs in Russia is presented.

  90. L Peyker, C Gold, E-W Scheidt, H Michor

    Substitution of nickel by copper in the heavy fermion system CeNi$_{9-x}$Cu$_x$Ge$_4$ alters the local crystal field environment of the Ce$^{3+}$-ions. This leads to a quantum phase transition near $x\approx0.4$, which is not only driven by the competition between Kondo effect and RKKY interaction, but also by a reduction of an effectively fourfold to a twof

  91. Hideki Matsumoto, Tatsuya Mori, Kei Iwamoto, Shohei Goshima

    Recently there has been paid much attention to phenomena caused by local anharmonic vibrations of the guest ions encapsulated in polyhedral cages of materials such as pyrochlore oxides, filled skutterdites and clathrates. We theoretically investigate the optical conductivity solely due to these so-called rattling phonons in a one-dimensional anharmonic poten

  92. Pierre Cocheteux, Alexandre Voisin, Eric Levrat, Benoît Iung

    Maintenance plays now a critical role in manufacturing for achieving important cost savings and competitive advantage while preserving product conditions. It suggests moving from conventional maintenance practices to predictive strategy. Indeed the maintenance action has to be done at the right time based on the system performance and component Remaining Use

  93. Guoshuang Pan

    There are ten chapters in this dissertation, which focuses on nine contents: growth estimates for a class of subharmonic functions in the half plane; growth estimates for a class of subharmonic functions in the half space; a generalization of harmonic majorants; properties of limit for Poisson integral; a lower bound for a class of harmonic functions in the

  94. Ute von Wangenheim, Ellen Baake, Michael Baake

    Modelling the process of recombination leads to a large coupled nonlinear dynamical system. Here, we consider a particular case of recombination in {\em discrete} time, allowing only for {\em single crossovers}. While the analogous dynamics in {\em continuous} time admits a closed solution, this no longer works for discrete time. A more general model (i.e. w

  95. Pablo Piantanida, Gerald Matz, Pierre Duhamel

    Communication systems are usually designed by assuming perfect channel state information (CSI). However, in many practical scenarios, only a noisy estimate of the channel is available, which may strongly differ from the true channel. This imperfect CSI scenario is addressed by introducing the notion of estimation-induced outage (EIO) capacity. We derive a si

  96. Thomas R. Weikl, Mesfin Asfaw, Heinrich Krobath, Bartosz Rozycki

    Cell membranes interact via anchored receptor and ligand molecules. Central questions on cell adhesion concern the binding affinity of these membrane-anchored molecules, the mechanisms leading to the receptor-ligand domains observed during adhesion, and the role of cytoskeletal and other active processes. In this review, these questions are addressed from a

  97. Gisella Clementini

    Pulsating variable stars can be powerful tools to study the structure, formation and evolution of galaxies. I discuss the role that the Magellanic Clouds&#39; pulsating variables play in our understanding of the whole Magellanic System, in light of results on pulsating variables produced by extensive observing campaigns like the MACHO and OGLE microlensing s

  98. Bolanle Oladejo, Adenike Osofisan, Victor Odumuyiwa

    People have to make important decisions within a time frame. Hence, it is imperative to employ means or strategy to aid effective decision making. Consequently, Economic Intelligence (EI) has emerged as a field to aid strategic and timely decision making in an organization. In the course of attaining this goal: it is indispensable to be more optimistic towar

  99. James E. Dale, Richard Wunsch, Anthony Whitworth, Jan Palous

    We investigate the gravitational fragmentation of expanding shells in the context of the linear thin--shell analysis. We make use of two very different numerical schemes; the FLASH Adaptive Mesh Refinement code and a version of the Benz Smoothed Particle Hydrodynamics code. We find that the agreement between the two codes is excellent. We use our numerical r

  100. Hamid Saleem

    It is pointed out that electron thermal fluctuations can couple with the ion acoustic mode in an inhomogeneous plasma to generate a low frequency ion time scale electromagnetic wave. This electromagnetic wave can become unstable if the temperature and density gradients are parallel to each other which can be the case in laser-plasmas similar to stellar cores