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Sep 18, 2013
09/13

by
John Gibbons; Darryl D Holm; Cesare Tronci

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The Vlasov equation for the collisionless evolution of the single-particle probability distribution function (PDF) is a well-known Lie-Poisson Hamiltonian system. Remarkably, the operation of taking the moments of the Vlasov PDF preserves the Lie-Poisson structure. The individual particle motions correspond to singular solutions of the Vlasov equation. The paper focuses on singular solutions of the problem of geodesic motion of the Vlasov moments. These singular solutions recover geodesic...

Source: http://arxiv.org/abs/0705.3603v1

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Sep 18, 2013
09/13

by
Jaita Paul; Takeshi Nishimatsu; Y. Kawazoe; Umesh V. Waghmare

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We present molecular dynamics simulations of a realistic model of an ultrathin film of BaTiO$_3$ sandwiched between short-circuited electrodes to determine and understand effects of film thickness, epitaxial strain and the nature of electrodes on its ferroelectric phase transitions as a function of temperature. We determine a full epitaxial strain-temperature phase diagram in the presence of perfect electrodes. Even with the vanishing depolarization field, we find that ferroelectric phase...

Source: http://arxiv.org/abs/0705.3504v1

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Sep 18, 2013
09/13

by
A. Chia; A. S. Parkins

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We study quantum trajectories of collective atomic spin states of $N$ effective two-level atoms driven with laser and cavity fields. We show that interesting ``entangled-state cycles'' arise probabilistically when the (Raman) transition rates between the two atomic levels are set equal. For odd (even) $N$, there are $(N+1)/2$ ($N/2$) possible cycles. During each cycle the $N$-qubit state switches, with each cavity photon emission, between the states $(|N/2,m>\pm |N/2,-m>)/\sqrt{2}$, where...

Source: http://arxiv.org/abs/0705.3506v1

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Sep 18, 2013
09/13

by
P. Pedram; S. Jalalzadeh; S. S. Gousheh

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We present a chaplygin gas Friedmann-Robertson-Walker quantum cosmological model. In this work the Schutz's variational formalism is applied with positive, negative, and zero constant spatial curvature. In this approach the notion of time can be recovered. These give rise to Schr\"odinger-Wheeler-DeWitt equation for the scale factor. We use the eigenfunctions in order to construct wave packets for each case. We study the time dependent behavior of the expectation value of the scale factor,...

Source: http://arxiv.org/abs/0705.3587v1

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Sep 18, 2013
09/13

by
Ken-ji Hamada; Shinichi Horata; Naoshi Sugiyama; Tetsuyuki Yukawa

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The angular power spectra of cosmic microwave background are analyzed under the light of the evolutional scenario of the universe based on the renormalizable quantum theory of gravity in four dimensions. The equation of evolution is solved numerically fixing the power law spectrum predicted by the conformal gravity for the initial condition. The equation requires to introduce a dynamical energy scale about 10^{17}GeV, where the inflationary space-time evolution makes a transition to the...

Source: http://arxiv.org/abs/0705.3490v1

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Sep 18, 2013
09/13

by
C. M. Pooley; G. P. Alexander; J. M. Yeomans

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We investigate the hydrodynamic interactions between microorganisms swimming at low Reynolds number. By considering simple model swimmers, and combining analytic and numerical approaches, we investigate the time-averaged flow field around a swimmer. At short distances the swimmer behaves like a pump. At large distances the velocity field depends on whether the swimming stroke is invariant under a combined time-reversal and parity transformation. We then consider two swimmers and find that the...

Source: http://arxiv.org/abs/0705.3612v1

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Sep 18, 2013
09/13

by
Guglielmo Fucci; Bixiang Wang; Preeti Singh

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We prove the existence of a global attractor for the Newton-Boussinesq equation defined in a two-dimensional channel. The asymptotic compactness of the equation is derived by the uniform estimates on the tails of solutions. We also establish the regularity of the global attractor.

Source: http://arxiv.org/abs/0705.3671v1

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Sep 18, 2013
09/13

by
Ben Kilminster

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The CDF and D{\O} experiments at the Tevatron are currently the only capable of searching for the Standard Model Higgs boson. This article describes their most sensitive searches in the expected Higgs mass range, focusing on advanced methods used to extract the maximal sensitivity from the data. CDF presents newly updated results for $H \to W^+W^-$ and $ZH \to l^+l^- b\bar{b}$. D{\O}\ presents two new searches for $WH \to l\nu b\bar{b}$. These new analyses use the same 1 fb$^{-1}$ dataset as...

Source: http://arxiv.org/abs/0705.3513v1

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Sep 18, 2013
09/13

by
Qingjuan Yu; Piero Madau

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Hypervelocity stars (HVSs) ejected by the massive black hole at the Galactic center have unique kinematic properties compared to other halo stars. Their trajectories will deviate from being exactly radial because of the asymmetry of the Milky Way potential produced by the flattened disk and the triaxial dark matter halo, causing a change of angular momentum that can be much larger than the initial small value at injection. We study the kinematics of HVSs and propose an estimator of dark halo...

Source: http://arxiv.org/abs/0705.3514v1

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Sep 18, 2013
09/13

by
Boris A. Popov

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Recent results from the HARP experiment on the measurements of the double-differential production cross-section of pions in proton interactions with beryllium, carbon and tantalum targets are presented. These results are relevant for a detailed understanding of neutrino flux in accelerator neutrino experiments MiniBooNE/SciBooNE, for a better prediction of atmospheric neutrino fluxes as well as for an optimization of a future neutrino factory design.

Source: http://arxiv.org/abs/0705.3512v1

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Sep 18, 2013
09/13

by
Madalin Guta; Anna Jencova

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The theory of local asymptotic normality for quantum statistical experiments is developed in the spirit of the classical result from mathematical statistics due to Le Cam. Roughly speaking, local asymptotic normality means that the family varphi_{\theta_{0}+ u/\sqrt{n}}^{n} consisting of joint states of n identically prepared quantum systems approaches in a statistical sense a family of Gaussian state phi_{u} of an algebra of canonical commutation relations. The convergence holds for all...

Source: http://arxiv.org/abs/quant-ph/0606213v2

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Sep 18, 2013
09/13

by
Chi Hin Chan; Alexis Vasseur

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This article is devoted to a Log improvement of Prodi-Serrin criterion for global regularity to solutions to Navier-Stokes equations in dimension 3. It is shown that the global regualrity holds under the condition that |u|^5/ log (1+|u|) is integrable in space time variables.

Source: http://arxiv.org/abs/0705.3659v1

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Sep 21, 2013
09/13

by
A. Ochab-Marcinek; A. Fiasconaro; E. Gudowska-Nowak; B. Spagnolo

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We study a Langevin equation derived from the Michaelis-Menten (MM) phenomenological scheme for catalysis accompanying a spontaneous replication of molecules, which may serve as a simple model of cell-mediated immune surveillance against cancer. We examine how two different and statistically independent sources of noise - dichotomous multiplicative noise and additive Gaussian white noise - influence the population's extinction time. This quantity is identified as the mean first passage time of...

Source: http://arxiv.org/abs/q-bio/0602016v2

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Sep 18, 2013
09/13

by
Eilat Glikman; S. G. Djorgovski; Daniel Stern; Milan Bogosavljevic; Ashish Mahabal

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We report the discovery of two low-luminosity quasars at z~4, both of which show prominent N IV] 1486A emission. This line is extremely rare in quasar spectra at any redshift; detecting it in two out of a sample of 23 objects (i.e., ~ 9% of the sample) is intriguing and is likely due to the low-luminosity, high-redshift quasar sample we are studying. This is still a poorly explored regime, where contributions from associated, early starbursts may be significant. One interpretation of this line...

Source: http://arxiv.org/abs/0705.3638v1

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Sep 19, 2013
09/13

by
Gao-Chan Yong; Bao-An Li; Lie-Wen Chen

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Within a transport model it is shown that the neutron/proton ratio of squeezed-out nucleons perpendicular to the reaction plane, especially at high transverse momenta, in heavy-ion reactions induced by high energy neutron-rich nuclei can be a useful tool for studying the high density behavior of the nuclear symmetry energy.

Source: http://arxiv.org/abs/nucl-th/0703042v2

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Sep 22, 2013
09/13

by
J. R. Shepard

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Three-body recombination rates for cold $^4$He are calculated with a new method which exploits the simple relationship between the imaginary part of the atom-dimer elastic scattering phase shift and the $S$-matrix for recombination. The elastic phase shifts are computed above breakup threshold by solving a three-body Faddeev equation in momentum space with inputs based on a variety of modern atom-atom potentials. Recombination coefficients for the HFD-B3-FCII potential agree very well with the...

Source: http://arxiv.org/abs/cond-mat/0702290v2

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Sep 18, 2013
09/13

by
Mattia Luzzi

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We apply several methods related to the WKB approximation to study cosmological perturbations during inflation, obtaining the full power spectra of scalar and tensor perturbations to first and to second order in the slow-roll parameters. We compare our results with those derived by means of other methods, in particular the Green's function method, and find agreement for the slow-roll structure. Scalar wave propagation on the Schwarzschild background is also considered.

Source: http://arxiv.org/abs/0705.3764v1

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Sep 20, 2013
09/13

by
V. W. Scarola; S. Das Sarma

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We theoretically study the observable response of edge currents in two dimensional cold atom optical lattices. As an example we use Gutzwiller mean-field theory to relate persistent edge currents surrounding a Mott insulator in a slowly rotating trapped Bose-Hubbard system to time of flight measurements. We briefly discuss an application, the detection of Chern number using edge currents of a topologically ordered optical lattice insulator.

Source: http://arxiv.org/abs/cond-mat/0612302v2

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Sep 18, 2013
09/13

by
Joshua D. MacArthur; Raymond G. McLenaghan; Roman G. Smirnov

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The interplay between the Hamilton-Jacobi theory of orthogonal separation of variables and the theory of group actions is investigated based on concrete examples.

Source: http://arxiv.org/abs/0705.3628v1

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Sep 18, 2013
09/13

by
Ulf-G. Meißner; A. M. Rakhimov; A. Wirzba; U. T. Yakhshiev

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Isospin-breaking effects in the baryonic sector are studied in the framework of a medium-modified Skyrme model. The neutron-proton mass difference in infinite, asymmetric nuclear matter is discussed. In order to describe the influence of the nuclear environment on the skyrmions, we include energy-dependent charged and neutral pion optical potentials in the s- and p-wave channels. The present approach predicts that the neutron-proton mass difference is mainly dictated by its strong part and that...

Source: http://arxiv.org/abs/0705.1603v2

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Sep 19, 2013
09/13

by
H. Albrecht

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In this paper we describe the operation and performance of the HERA-B Outer Tracker, a 112674 channel system of planar drift tube layers. The performance of the HERA-B Outer Tracker system fullfilled all requirements for stable and efficient operation in a hadronic environment, thus confirming the adequacy of the honeycomb drift tube technology and of the front-end readout system. The detector was stably operated with a gas gain of 30000 in an Ar/CF4/CO2 (65:30:5) gas mixture, yielding a good...

Source: http://arxiv.org/abs/physics/0701122v2

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92

Jul 20, 2013
07/13

by
L. M. Jensen; J. Kinnunen; P. Torma

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Superconductivity and superfluidity of fermions require, within the BCS theory, matching of the Fermi energies of the two interacting Fermion species. Difference in the number densities of the two species leads either to a normal state, to phase separation, or - potentially - to exotic forms of superfluidity such as FFLO-state, Sarma state or breached pair state. We consider ultracold Fermi gases with polarization, i.e. spin-density imbalance. We show that, due to the gases being trapped and...

Source: http://arxiv.org/abs/cond-mat/0604424v4

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Sep 18, 2013
09/13

by
H. M. Yehia

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This paper aims at the most comprehensive and systematic construction and tabulation of mechanical systems that admit a second invariant, quadratic in velocities, other than the Hamiltonian. The configuration space is in general a 2D Riemannian or pseudo-Riemannian manifold and the determination of its geometry is a part of the process of solution. Forces acting on the system include a part derived from a scalar potential and a part derived from a vector potential, associated with terms linear...

Source: http://arxiv.org/abs/0705.3676v1

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Sep 18, 2013
09/13

by
Jan Dreiser; Mete Atature; Christophe Galland; Tina Muller; Antonio Badolato; Atac Imamoglu

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We have performed all-optical measurements of spin relaxation in single self-assembled InAs/GaAs quantum dots (QD) as a function of static external electric and magnetic fields. To study QD spin dynamics we measure the degree of resonant absorption which results from a competition between optical spin pumping induced by the resonant laser field and spin relaxation induced by reservoirs. Fundamental interactions that determine spin dynamics in QDs are hyperfine coupling to QD nuclear spin...

Source: http://arxiv.org/abs/0705.3557v1

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Sep 19, 2013
09/13

by
James Gray; Yang-Hui He; Anton Ilderton; Andre Lukas

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One of the central problems of string-phenomenology is to find stable vacua in the four dimensional effective theories which result from compactification. We present an algorithmic method to find all of the vacua of any given string-phenomenological system in a huge class. In particular, this paper reviews and then extends hep-th/0606122 to include various non-perturbative effects. These include gaugino condensation and instantonic contributions to the superpotential.

Source: http://arxiv.org/abs/hep-th/0703249v2

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Sep 18, 2013
09/13

by
Debajyoti Choudhury; Dilip Kumar Ghosh; Mamta

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Recently Georgi has discussed the possible existence of `Unparticles' describable by operators having non-integral scaling dimensions. With the interaction of these with the Standard Model (SM) particles being constrained only by gauge and Lorentz symmetries, it affords a new source for lepton flavour violation. Current and future muon decay experiments are shown to be very sensitive to such scenarios.

Source: http://arxiv.org/abs/0705.3637v1

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Sep 18, 2013
09/13

by
Ivan Sanchez; Franck Raynaud; Jose Lanuza; Bruno Andreotti; Eric Clement; Igor S. Aranson

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The influence of controlled vibrations on the granular rheology is investigated in a specifically designed experiment. We study experimentally a thin granular film spreading under the action of horizontal vibrations. A nonlinear diffusion equation is derived theoretically that describes the evolution of the deposit shape. A self-similar parabolic shape (the``granular droplet'') and a spreading dynamics are predicted that both agree quantitatively with the experimental results. The theoretical...

Source: http://arxiv.org/abs/0705.3552v1

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Sep 18, 2013
09/13

by
James P Smith

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This thesis studies some examples of families of K3 surfaces with Picard lattices of maximal rank. These families occur as invariants of finite automorphism groups. The Picard-Fuchs differential equations describing the variation of Hodge structure in these families are considered. Techniques are developed to find the corresponding monodromy groups as arithmetic Fuchsian groups acting on the families' period spaces.

Source: http://arxiv.org/abs/0705.3658v1

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Sep 18, 2013
09/13

by
Dan Hooper; Douglas P. Finkbeiner; Gregory Dobler

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The WMAP experiment has revealed an excess of microwave emission from the region around the center of our Galaxy. It has been suggested that this signal, known as the ``WMAP Haze'', could be synchrotron emission from relativistic electrons and positrons generated in dark matter annihilations. In this letter, we revisit this possibility. We find that the angular distribution of the WMAP Haze matches the prediction for dark matter annihilations with a cusped density profile, $\rho(r) \propto...

Source: http://arxiv.org/abs/0705.3655v1

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Sep 18, 2013
09/13

by
James McKee; Chris Smyth

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We completely describe all integer symmetric matrices that have all their eigenvalues in the interval [-2,2]. Along the way we classify all signed graphs, and then all charged signed graphs, having all their eigenvalues in this same interval. We then classify subsets of the above for which the integer symmetric matrices, signed graphs and charged signed graphs have all their eigenvalues in the open interval (-2,2).

Source: http://arxiv.org/abs/0705.3599v1

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Sep 23, 2013
09/13

by
Antal A. Jarai; Frank Redig

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We study the Abelian sandpile model on Z^d. In dimensions at least 3 we prove existence of the infinite volume addition operator, almost surely with respect to the infinite volume limit mu of the uniform measures on recurrent configurations. We prove the existence of a Markov process with stationary measure mu, and study ergodic properties of this process. The main techniques we use are a connection between the statistics of waves and uniform two-component spanning trees and results on the...

Source: http://arxiv.org/abs/math/0408060v3

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Sep 18, 2013
09/13

by
Daniel Feldman; Zuowei Liu; Pran Nath

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A overview is given of the recent developments in the $U(1)_X$ Stueckelberg extensions of the Standard Model and of MSSM where all the Standard Model particles are neutral under the $U(1)_X$ but an axion which is absorbed is charged under both $U(1)_X$ and $U(1)_Y$ and acts as the connector field coupling the Standard Model sector with the Stueckelberg sector. Coupled with the usual Higgs mechanism that breaks the $SU(2)_L\times U(1)_Y$ gauge symmetry, this scenario produces mixings in the...

Source: http://arxiv.org/abs/0705.2924v2

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Sep 18, 2013
09/13

by
J. C. Suarez; E. Michel; G. Houdek; F. Perez Hernandez; Y. Lebreton

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A comparison between linear stability analysis and observations of pulsation modes in five delta Scuti stars, belonging to the same cluster, is presented. The study is based on the work by Michel et al. (1999), in which such a comparison was performed for a representative set of model solutions obtained independently for each individual star considered. In this paper we revisit the work by Michel et al. (1999) following, however, a new approach which consists in the search for a single,...

Source: http://arxiv.org/abs/0705.3626v1

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Sep 18, 2013
09/13

by
G. Everest; R. Miles; S. Stevens; T. Ward

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We introduce a class of group endomorphisms -- those of finite combinatorial rank -- exhibiting slow orbit growth. An associated Dirichlet series is used to obtain an exact orbit counting formula, and in the connected case this series is shown to have a closed rational form. Analytic properties of the Dirichlet series are related to orbit-growth asymptotics: depending on the location of the abscissa of convergence and the degree of the pole there, various orbit-growth asymptotics are found, all...

Source: http://arxiv.org/abs/0705.1067v2

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Sep 18, 2013
09/13

by
Luisa Beghin

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We study here a heat-type differential equation of order n greater than two, in the case where the time-derivative is supposed to be fractional. The corresponding solution can be described as the transition function of a pseudoprocess (coinciding with the one governed by the standard, non-fractional, equation) with a time argument T which is itself random. The distribution of T is presented together with some features of the solution (such as analytic expressions for its moments).

Source: http://arxiv.org/abs/0705.3598v1

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Sep 18, 2013
09/13

by
Guangfei Jiang; C. S. Kochanek

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We jointly model 22 early-type gravitational lens galaxies with stellar dynamical measurements using standard CDM halo models. The sample is inhomogeneous in both its mass distributions and the evolution of its stellar populations unless the true uncertainties are significantly larger than the reported measurement errors. In general, the individual systems cannot constrain halo models, in the sense that the data poorly constrains the stellar mass fraction of the halo. The ensemble of systems,...

Source: http://arxiv.org/abs/0705.3647v1

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Sep 18, 2013
09/13

by
Zaira Nazario; David I. Santiago

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The Mott critical point between a metal and a correlated insulator has usually been studied via density or spin density bosonic mode fluctuations according to the standard Ginzburg-Landau-Wilson phase transition paradigm. A moment's reflection leads to increasing doubts that such an approach should work as the transition is nonmagnetic, voiding the relevance of spin density modes. Charge density modes are irrelevelant since the long range Coulomb interaction leads to a large plasmon gap and...

Source: http://arxiv.org/abs/0705.3653v1

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Sep 18, 2013
09/13

by
Alexander E. Hramov; Alexey A. Koronovskii; Vladimir I. Ponomarenko; Mikhail D. Prokhorov

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A method is proposed for detecting from univariate data the presence of synchronization of a self-sustained oscillator by external driving with varying frequency. The method is based on the analysis of difference between the oscillator instantaneous phases calculated using continuous wavelet transform at time moments shifted by a certain constant value relative to each other. We apply our method to a driven asymmetric van der Pol oscillator, experimental data from a driven electronic oscillator...

Source: http://arxiv.org/abs/0705.3544v1

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Sep 18, 2013
09/13

by
L. V. Sales; J. F. Navarro; M. G. Abadi; M. Steinmetz

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We examine the orbits of satellite galaxies identified in a suite of N-body/gasdynamical simulations of the formation of $L_*$ galaxies in a LCDM universe. Most satellites follow conventional orbits; after turning around, they accrete into their host halo and settle on orbits whose apocentric radii are steadily eroded by dynamical friction. However, a number of outliers are also present, we find that ~1/3 of satellites identified at $z=0$ are on unorthodox orbits, with apocenters that exceed...

Source: http://arxiv.org/abs/0704.1773v2

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Sep 18, 2013
09/13

by
Chuan-Hua Xiong

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The hidden symmetry and an infinite set non-local conserved currents of the Green-Schwarz superstring on $AdS_5\otimes S^5$ have been pointed out by Bena et al. In this paper, we shown that the Hodge dual between the Maurer-Cartan equation and the equation of motion gives the hidden symmetry in the moduli space of Green-Schwarz superstring. Thus by twisty transforming the vielbeins, we can express the currents of the paper$^{\cite{bpr}}$ as the Lax connections by a unique spectral parameter.

Source: http://arxiv.org/abs/0705.3546v1

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Sep 18, 2013
09/13

by
A. Ardizzoni; C. Menini

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In this paper we continue the investigation started in [A.M.St.-Small], dealing with bialgebras $A$ with an $H$-bilinear coalgebra projection over an arbitrary subbialgebra $H$ with antipode. These bialgebras can be described as deformed bosonizations $R#_{\xi} H$ of a pre-bialgebra $R$ by $H$ with a cocycle $\xi$. Here we describe the behavior of $\xi$ in the case when $R$ is f.d. and thin i.e. it is connected with one dimensional space of primitive elements. This is used to analyze the...

Source: http://arxiv.org/abs/0705.3522v1

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Sep 18, 2013
09/13

by
Hooman Davoudiasl; Sash Sarangi; Gary Shiu

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We consider the phenomenological consequences of sampling multiple vacua during inflation motivated by an enormous landscape. A generic consequence of this sampling is the formation of domain walls, characterized by the scale $\mu$ of the barriers that partition the accessed vacua. We find that the success of Big Bang Nucleosynthesis (BBN) implies $\mu \gsim 10$ TeV, as long as the sampled vacua have a non-degeneracy larger than $\cal{O}({{\rm MeV}}^{\rm 4})$. Otherwise, the walls will dominate...

Source: http://arxiv.org/abs/hep-th/0611232v3

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Sep 23, 2013
09/13

by
Claude Sabbah

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We show that the Fourier-Laplace transform of an irreducible regular differential system on the Riemann sphere underlies, when one only considers the part at finite distance, a polarizable regular twistor $\mathcal{D}$-module. The associated holomorphic bundle out of the origin is therefore equipped with a natural harmonic metric with a tame behaviour near the origin.

Source: http://arxiv.org/abs/math/0408294v2

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Sep 18, 2013
09/13

by
K. R. Goodearl; S. Launois

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The structure of Poisson polynomial algebras of the type obtained as semiclassical limits of quantized coordinate rings is investigated. Sufficient conditions for a rational Poisson action of a torus on such an algebra to leave only finitely many Poisson prime ideals invariant are obtained. Combined with previous work of the first-named author, this establishes the Poisson Dixmier-Moeglin equivalence for large classes of Poisson polynomial rings, such as semiclassical limits of quantum...

Source: http://arxiv.org/abs/0705.3486v1

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Sep 18, 2013
09/13

by
Alejandro Rodriguez; Marin Soljacic; John D. Joannopoulos; Steven G. Johnson

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We derive general conditions for 100 percent frequency conversion in any doubly resonant nonlinear cavity, for both second- and third-harmonic generation via chi2 and chi3 nonlinearities. We find that conversion efficiency is optimized for a certain critical power depending on the cavity parameters, and assuming reasonable parameters we predict 100 percent conversion using milliwatts of power or less. These results follow from a semi-analytical coupled-mode theory framework which is generalized...

Source: http://arxiv.org/abs/0705.3652v1

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Sep 19, 2013
09/13

by
Wojciech De Roeck

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Quantum extensions of the Gallavotti-Cohen fluctuation theorem (FT) for the entropy production have been discussed by several authors. There is a practical gap between microscopic forms of FT and mesoscopic (i.e. not purely Hamiltonian) forms for open systems. In a microscopic setup, it is easy to state and to prove FT. In a mesoscopic setup, it is difficult to identify fluctuations of the entropy production. (This difficulty is absent in the classical case.) We discuss a particular mesoscopic...

Source: http://arxiv.org/abs/cond-mat/0703347v2

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Sep 18, 2013
09/13

by
S. Kondrat; L. Harnau; S. Dietrich

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We consider a non-spherical colloidal particle immersed in a fluid close to its critical point. The temperature dependence of the corresponding order parameter profile is calculated explicitly. We perform a systematic expansion of the order parameter profile in powers of the local curvatures of the surface of the colloidal particle. This curvature expansion reduces to the short distance expansion of the order parameter profile in the case that the solvent is at the critical composition.

Source: http://arxiv.org/abs/0705.3326v2

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28

Sep 18, 2013
09/13

by
Lucas Bordeaux; Marco Cadoli; Toni Mancini

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Quantified constraints and Quantified Boolean Formulae are typically much more difficult to reason with than classical constraints, because quantifier alternation makes the usual notion of solution inappropriate. As a consequence, basic properties of Constraint Satisfaction Problems (CSP), such as consistency or substitutability, are not completely understood in the quantified case. These properties are important because they are the basis of most of the reasoning methods used to solve...

Source: http://arxiv.org/abs/0705.3561v1

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40

Sep 18, 2013
09/13

by
Wen-jun Liu; Qiao-ling Xue; Jian-wei Dong

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Generalizations of Ostrowski type inequality for functions of Lipschitzian type are established. Applications in numerical integration and cumulative distribution functions are also given.

Source: http://arxiv.org/abs/0705.3556v1

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44

Sep 18, 2013
09/13

by
P. Székely; L. L. Kiss; K. Szatmáry; B. Csák; G. Á. Bakos; T. R. Bedding

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Using the recently commissioned multi-object spectrograph AAOmega on the 3.9m AAT we have obtained medium-resolution near-infrared spectra for 10,500 stars in and around five southern globular clusters. The targets were 47 Tuc, M12, M30, M55 and NGC 288. We have measured radial velocities to +/- 1 km/s with the cross correlation method and estimated metallicity, effective temperature, surface gra vity and rotational velocity for each star by fitting synthetic model spectra. An analysis of the...

Source: http://arxiv.org/abs/0705.3562v1