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November 2010 arXiv papers — page 20

Showing 1,9012,000 of 6,505 papers

  1. David Arthur, Steve Y. Oudot

    We investigate the problem of finding reverse nearest neighbors efficiently. Although provably good solutions exist for this problem in low or fixed dimensions, to this date the methods proposed in high dimensions are mostly heuristic. We introduce a method that is both provably correct and efficient in all dimensions, based on a reduction of the problem to

  2. Arno Bohm, Peter W. Bryant

    In quantum mechanical experiments one distinguishes between the state of an experimental system and an observable measured in it. Heuristically, the distinction between states and observables is also suggested in scattering theory or when one expresses causality. We explain how this distinction can be made also mathematically. The result is a theory with asy

  3. Gil Paz

    This talk discusses recent developments in the theory of inclusive radiative B decays, focusing mainly on non-perturbative aspects of B->Xs gamma.

  4. Manfred Lindner, Alexander Merle, Viviana Niro

    We discuss how a $L_e-L_μ-L_τ$ flavour symmetry that is softly broken leads to keV sterile neutrinos, which are a prime candidate for Warm Dark Matter. This is to our knowledge the first model where flavour symmetries are applied simultaneously to active and sterile neutrinos explaining at the same time active neutrino properties and this peculiar Dark Matte

  5. Eve C. Ostriker

    Star formation depends on the available gaseous "fuel" as well as galactic environment, with higher specific star formation rates where gas is predominantly molecular and where stellar (and dark matter) densities are higher. The partition of gas into different thermal components must itself depend on the star formation rate, since a steady state dist

  6. Werner Rodejohann

    Neutrinoless double beta decay is a process of fundamental importance for particle physics. It can be mediated by light massive Majorana neutrinos (standard interpretation) or by something else (non-standard interpretations). We review its dependence on the neutrino parameters, its complementarity to other observables sensitive to neutrino mass, and emphasiz

  7. B. Goutéraux

    In this thesis, we wish to examine the black-hole solutions of modified gravity theories inspired by String Theory or Cosmology. Namely, these modifications will take the guise of additional gauge and scalar fields for the so-called Einstein-Maxwell-Dilaton theories with an exponential Liouville potential; and of extra spatial dimensions for Einstein-Gauss-B

  8. Rainer J. Klement, Johny Setiawan, Thomas Henning, Hans-Walter Rix

    We report the detection of a planetary companion around HIP 13044, a metal-poor red horizontal branch star belonging to a stellar halo stream that results from the disruption of an ancient Milky Way satellite galaxy. The detection is based on radial velocity observations with FEROS at the 2.2-m MPG/ESO telescope. The periodic radial velocity variation of P=1

  9. Alexander A. Sherstov

    A strong direct product theorem (SDPT) states that solving n instances of a problem requires Omega(n) times the resources for a single instance, even to achieve success probability exp(-Omega(n)). We prove that quantum communication complexity obeys an SDPT whenever the communication lower bound for a single instance is proved by the generalized discrepancy

  10. Sergey S. Kokarev

    Relations between kinematics, geometry and law of reference frame motion are considered. We show, that kinematical tensors define geometry up to a space functional arbitrariness when integrability condition for spin tensor is satisfied. Some aspects of geometrization principle and geometrical conventionalism of Poincare are discussed in a light of the obtain

  11. Anatoly E. Patrick

    Various substances in the liquid state tend to form droplets. In this paper the shape of such droplets is investigated within the spherical model of a lattice gas. We show that in this case the droplet boundary is always diffusive, as opposed to sharp, and find the corresponding density profiles (droplet shapes). Translation-invariant versions of the spheric

  12. David Tucker-Smith, Itay Yavin

    We explore the possibility that a new interaction between muons and protons is responsible for the discrepancy between the CODATA value of the proton radius and the value deduced from the measurement of the Lamb shift in muonic hydrogen. We show that a new force carrier with roughly MeV mass can account for the observed energy shift as well as the discrepanc

  13. C. Marois, B. Zuckerman, Q. M. Konopacky, B. Macintosh

    High-contrast near-infrared imaging of the nearby star HR 8799 has shown three giant planets. Such images were possible due to the wide orbits (> 25 AU) and youth (< 100 Myr) of the imaged planets, which are still hot and bright as they radiate away gravitational energy acquired during their formation. A major area of contention in the extrasolar planet comm

  14. Sergey Kovalenko, Heinrich Päs, Ivan Schmidt

    We examine lepton number violation (LNV) in theories with a saturated black hole bound on a large number of species. Such theories have been advocated recently as a possible solution to the hierarchy problem and an explanation of the smallness of neutrino masses. The violation of lepton number can be a potential phenomenological problem of this N-copy extens

  15. Y. Okada, C. Dhital, Wen-Wen Zhou, Hsin Lin

    In topological insulators (TI), strong spin-orbit coupling results in non-trivial scattering processes of the surface states, whose effects include suppressed back scattering1, 2, 3, 4 weak anti-localization5, 6 and the possibility of an exotic Kondo effect that mimics graphene7. Introducing time reversal breaking perturbations and establishing long-range ma

  16. Amelia Carolina Sparavigna

    The course of the Nile in northern Sudan follows a contorted path through bedrocks, creating the Great Bend. Few years ago, the satellite images showed a fertile strip of land with villages, where paleochannels of the river hosted many fields with cultivations and archaeological sites. Now, a huge part of this valley is under the waters of Merowe Dam reservo

  17. Dragana Bajovic, Bruno Sinopoli, Joao Xavier

    We consider the problem of sensor selection for event detection in wireless sensor networks (WSNs). We want to choose a subset of p out of n sensors that yields the best detection performance. As the sensor selection optimality criteria, we propose the Kullback-Leibler and Chernoff distances between the distributions of the selected measurements under the tw

  18. Jonathan Irwin, Zachory K. Berta, Christopher J. Burke, David Charbonneau

    We present rotation period measurements for 41 field M-dwarfs, all of which have masses inferred (from their parallaxes and 2MASS K-band magnitudes) to be between the hydrogen burning limit and 0.35 Msol, and thus should remain fully-convective throughout their lifetimes. We measure a wide range of rotation periods, from 0.28 days to 154 days, with the latte

  19. Nathan Argaman, Y. B. Band

    The thermodynamic approach to density functional theory (DFT) is used to derive a versatile theoretical framework for the treatment of finite-temperature (and in the limit, zero temperature) Bose-Einstein condensates (BECs). The simplest application of this framework, using the overall density of bosons alone, would yield the DFT of Nunes (1999). It is argue

  20. Pei-Hong Gu, Manfred Lindner

    We propose a left-right symmetric model to simultaneously give natural inflation and flavor mixing from a Peccei-Quinn symmetry breaking at the Planck scale. Our model can be embedded in SO(10) grand unification theories.

  21. I. I. Boiko

    Conductivity of p-Si and p-Ge is considered for two band model with due regard for mutual drag of light and heavy holes. It is shown that for small and moderate temperatures this drag significantly diminishes drift velocity of light holes and, as result, the total conductivity of crystal. Considered here drag-effect appears as well in the form of nonmonotono

  22. Yaakov S. Weinstein

    In this paper I explore the entanglement evolution of qubits that are part of a five qubit quantum error correction code subject to various decohering environments. Specifically, I look for possible parallels between the entanglement degradation and the fidelity of the logical qubit of quantum information stored in the physical qubits. In addition, I note th

  23. Sven Zschocke, Sergei A. Klioner

    Although the formulas for the light deflection due to quadrupole gravitational field of deflecting bodies are well known, the formulas are rather complicated, so that massive computations of quadrupole light deflection (e.g., in the framework of astrometric survey missions like Gaia) are time-consuming. Considering an observer situated within a few million k

  24. Chetan S. Mandayam Nayakar, R. Srikanth

    Both deterministic and indeterministic physical laws are incompatible with control by genuine (non-illusory) free will. We propose that an indeterministic dynamics can be $weakly$ compatible with free will (FW), whereby the latter acts by altering the probability distribution over allowed outcomes. In the quantum physical world, such a FW can collapse the wa

  25. Ajit Kumar Mohanty

    An one dimensional adiabatic model has been proposed for fusion of loosely bound and halo light nuclei with various heavy targets. It is shown that fusion cross sections at near and sub-barrier energies can be explained using a simple WKB tunneling through an adiabatic barrier without invoking breakup coupling explicitly. The model has been applied successfu

  26. B. Dubrovin, T. Skrypnyk

    Using classical double G of a Lie algebra g equipped with a classical R-operator we define two sets of mutually commuting functions with respect to the initial Lie-Poisson bracket on g* and its extensions. We consider in details examples of the Lie algebras g with the &#34;Adler--Kostant--Symes&#34; R-operators and the corresponding two sets of mutually comm

  27. Luca Salasnich

    We investigate the low-temperature thermodynamics of the unitary Fermi gas by introducing a model based on the zero-temperature spectra of both bosonic collective modes and fermonic single-particle excitations. We calculate the Helmholtz free energy and from it we obtain the entropy, the internal energy and the chemical potential as a function of the tempera

  28. A. B. Sossinsky

    A new type of knot energy is presented via real life experiments involving a thin resilient metallic tube. Knotted in different ways, the device mechanically acquires a uniquely determined (up to isometry) normal form at least when the original knot diagram has a small number of crossings, thus outperforming the famous Möbius energy due to Jun O&#39;Hara and

  29. S. Criscuoli, D. Del Moro, F. Giorgi, P. Romano

    We have investigated properties of photospheric Bright Points (BPs) observed in an Active Region during its decay phase and in a quiet Sun region. We have analyzed two sets of photospheric observations taken with IBIS (Interferometric Bidimensioal Spectrometer) at the NSO Dunn Solar Telescope. The first set consists of spectral data acquired in the Fe I 709.

  30. Juan José Montellano-Ballesteros, Eduardo Rivera-Campo

    The heterochromatic number hc(H) of a non-empty hypergraph H is the smallest integer k such that for every colouring of the vertices of H with exactly k colours, there is a hyperedge of H all of whose vertices have different colours. We denote by nu(H) the number of vertices of H and by tau(H) the size of the smallest set containing at least two vertices of

  31. Wen Fu, Dong Lai

    Recent hydrodynamical simulations have shown that differentially rotating neutron stars formed in core-collapse supernovae may develop global non-axisymmetric instabilities even when $T/|W|$ (the ratio of the rotational kinetic energy $T$ to the gravitational potential energy $|W|$) is relatively small (less than 0.1). Such low-$T/|W|$ instability can give r

  32. Olgur Celikbas And Mark E. Walker

    We define a variant of Hochster&#39;s theta pairing and prove that it is constant in flat families of modules over hypersurfaces with isolated singularities. As a consequence, we show that the theta pairing factors through the Grothendieck group modulo algebraic equivalence. Moreover, our result allows us, in certain situations, to translate the properties o

  33. Mihaly Varadi, Laurent Eyer, Stefan Jordan, Detlev Koester

    Our goal is to assess Gaia&#39;s performance on the period recovery of short period (p < 2 hours) and small amplitude variability. To reach this goal first we collected the properties of variable stars that fit the requirements described above. Then we built a database of synthetic light-curves with short period and low amplitude variability with time sampli

  34. Michele Caselle, Luca Castagnini, Alessandra Feo, Ferdinando Gliozzi

    We present Monte Carlo results for the thermodynamics of pure SU(N) gauge theories with $N=2,...,6$ in 2+1 dimensions. We focus on the confined phase region $T<T_c$ and study thermodynamics variables such as the trace of the energy-momentum tensor, pressure, energy and entropy density using the integral method. We also investigate scaling properties with $N$

  35. Martin Reidemeister, Alexander V. Krivov, Christopher C. Stark, Jean-Charles Augereau

    Context: The K2V star eps Eri hosts one known inner planet, an outer Kuiper belt analog, and an inner disk of warm dust. Spitzer/IRS measurements indicate that the warm dust is present at distances as close as a few AU from the star. Its origin is puzzling, since an &#34;asteroid belt&#34; that could produce this dust would be unstable because of the known i

  36. Natalia Martins, Delfim F. M. Torres

    We prove new l&#39;Hopital rules for monotonicity valid on an arbitrary time scale. Both delta and nabla monotonic l&#39;Hopital rules are obtained. As an example of application, we give some new upper and lower bounds for the exponential function of quantum calculus restricted to the q-scale.

  37. Ash Mohammad Abbas

    Analyzing the relationships among the parameters for quantifying the quality of research published in journals is a challenging task. In this paper, we analyze the relationships between impact factor, h-index, and g-index of a journal. To keep our analysis simple and easy to understand, we consider a generalized version of the impact factor where there is no

  38. T. Schneider, S. Weyeneth

    Various superconductors, including cuprate superconductors, exhibit peculiar features above the transition temperature T_c. In particular the observation of a large diamagnetism and Nernst signal in a wide temperature window above T_c attracted considerable attention. Noting that this temperature window exceeds the fluctuation dominated regime drastically an

  39. Irakli Patchkoria

    In this note we prove that the simplicial derived functors introduced by Tierney and Vogel [TV69] are naturally isomorphic to the cubical derived functors introduced by the author in [P09]. We also explain how this result generalizes the well-known fact that the simplicial and cubical singular homologies of a topological space are naturally isomorphic.

  40. I. Maqbool, J. A. Sheikh, P. A. Ganai, P. Ring

    We perform particle-number projected mean-field study using the recently developed symmetry-projected Hartree-Fock-Bogoliubov (HFB) equations. Realistic calculations have been performed in sd- and fp-shell nuclei using the shell model empirical intearctions, USD and GXPFIA. It is demonstrated that the mean-field results for energy surfaces, obtained with the

  41. Sigurd B. Angenent, James Isenberg, Dan Knopf

    Gu and Zhu have shown that Type-II Ricci flow singularities develop from nongeneric rotationally symmetric Riemannian metrics on $S^m$, for all $m\geq 3$. In this paper, we describe and provide plausibility arguments for a detailed asymptotic profile and rate of curvature blow-up that we predict such solutions exhibit.

  42. Nikolaos Kidonakis

    I present results for the resummation of soft-gluon contributions to QCD hard-scattering cross sections at next-to-next-to-leading logarithm accuracy. A key ingredient is the calculation of two-loop soft anomalous dimensions for the partonic processes. Explicit expressions and applications are provided for processes that involve massless partons and/or massi

  43. Sperello di Serego Alighieri

    We review the methods used to test for the existence of cosmological birefringence, i.e. a rotation of the plane of linear polarization for electromagnetic radiation traveling over cosmological distances, which might arise in a number of important contexts involving the violation of fundamental physical principles. The main methods use: (1) the radio polariz

  44. Éric Brunet, Bernard Derrida

    We show that all the time-dependent statistical properties of the rightmost points of a branching Brownian motion can be extracted from the traveling wave solutions of the Fisher-KPP equation. We show that the distribution of all the distances between the rightmost points has a long time limit which can be understood as the delay of the Fisher-KPP traveling

  45. Alexey Pak, Alexander Smirnov

    We present an algorithm that reveals relevant contributions in non-threshold-type asymptotic expansion of Feynman integrals about a small parameter. It is shown that the problem reduces to finding a convex hull of a set of points in a multidimensional vector space.

  46. Bruno Bellomo, Giuseppe Compagno, Rosario Lo Franco, Alessandro Ridolfo

    We investigate the dynamical behavior of entanglement in a system made by two solid-state emitters, as two quantum dots, embedded in two separated micro-cavities. In these solid-state systems, in addition to the coupling with the cavity mode, the emitter is coupled to a continuum of leaky modes providing additional losses and it is also subject to a phonon-i

  47. Andrew Zangwill, Dimitri D. Vvedensky

    Graphene, a hexagonal sheet of $sp^2$-bonded carbon atoms, has extraordinary properties which hold immense promise for future nanoelectronic applications. Unfortunately, the popular preparation methods of micromechanical cleavage and chemical exfoliation of graphite do not easily scale up for application purposes. Epitaxial graphene provides an attractive al

  48. A. I. Titov, B. Kampfer, H. Takabe, A. Hosaka

    The emission of $ν\barν$ pairs off electrons in a polarized ultra-intense electromagnetic (e.g.\ laser) wave field is analyzed. We elaborate on the significance of non-linear electrodynamics effects (i.e., multi-photon processes) and the peculiarities of neutrino production. Special attention is devoted to the convergence of the reaction probabilities as a f

  49. Grant M. Kennedy, Mark C. Wyatt

    Since the 1980&#39;s it has been becoming increasingly clear that the Solar System&#39;s irregular satellites are collisionally evolved. We derive a general model for the collisional evolution of an irregular satellite swarm and apply it to the Solar System and extrasolar planets. Our model reproduces the Solar System&#39;s complement of observed irregulars

  50. Liping Wang, Qiang Wang

    We study the explicit factorization of $2^n r$-th cyclotomic polynomials over finite field $\mathbb{F}_q$ where $q, r$ are odd with $(r, q) =1$. We show that all irreducible factors of $2^n r$-th cyclotomic polynomials can be obtained easily from irreducible factors of cyclotomic polynomials of small orders. In particular, we obtain the explicit factorizatio

  51. Francesco Sylos Labini

    We study the statistical properties of the Luminous Red Galaxies sample from the Sloan Digital Sky Survey. In particular we test, by determining the probability density function (PDF) of galaxy (conditional) counts in spheres, whether statistical properties are self-averaging within the sample. We find that there are systematic differences in the shape of th

  52. Alexey A. Kuznetsov

    The electron-cyclotron maser instability (ECMI) is responsible for generation of the planetary auroral radio emissions. Most likely, the same mechanism produces radio bursts from ultracool dwarfs. We investigate amplification of plasma waves by the horseshoe-like electron distribution (similar to those observed in the terrestrial magnetosphere) as well as re

  53. Andrzej J. Buras, Minoru Nagai, Paride Paradisi

    Supersymmetric (SUSY) Grand Unified theories (GUTs) generally predict FCNC and CP violating processes to occur both in the leptonic and hadronic sectors. Assuming an underlying SU(5) group plus right-handed neutrinos (RN), we perform an extensive study of FCNC and CP violation, analyzing the correlations between leptonic and hadronic processes like mu-> e ga

  54. R. Grützbauch, F. Annibali, R. Rampazzo, A. Bressan

    We study stellar population parameters of a sample of 13 dwarf galaxies located in poor groups of galaxies using high resolution spectra observed with VIMOS at the ESO-VLT. LICK-indices were compared with Simple Stellar Population models to derive ages, metallicities and [alpha/Fe]-ratios. Comparing the dwarfs with a sample of giant ETGs residing in comparab

  55. J. Suffczynski, A. Grois, W. Pacuski, A. Golnik

    Near band-gap photoluminescence and reflectivity in magnetic field are employed to determine the exchange-induced splitting of free exciton states in paramagnetic wurtzite Ga1-xMnxN, x < 1%, grown on sapphire substrates by metal-organic vapor phase epitaxy. The band gap is found to increase with x. The giant Zeeman splitting of all three excitons A, B and C

  56. Ruth Grützbauch, Robert W. Chuter, Christopher J. Conselice, Amanda E. Bauer

    We study the relationship between galaxy colour, stellar mass, and local galaxy density in a deep near-infrared imaging survey up to a redshift of z~3 using the GOODS NICMOS Survey (GNS). The GNS is a deep near-infrared Hubble Space Telescope survey imaging a total of 45 square arcminutes of the GOODS fields, reaching a stellar mass completeness limit of log

  57. Peter Gilkey, Stana Nikcevic

    We show that the Weyl structure of an almost-Hermitian Weyl manifold of dimension at least 6 is trivial if the associated curvature operator satisfies the Kaehler identity. Similarly if the curvature of an almost para-Hermitian Weyl manifold of dimension at least 6 satisfies the para-Kaehler identity, then the Weyl structure is trivial as well.

  58. P. A. Boldin, S. B. Popov, N. Tetzlaff

    We present a new web-tool - Net-PSICoNS - for population synthesis of isolated near-by cooling neutron stars (NSs). The main aim is to provide an easy test of models of the NS thermal evolution which can be used by groups studying this subject. A user can upload cooling curves for a set of masses, modify the mass spectrum if necessary, change radii to fit th

  59. C. M. Fromm, M. Perucho, T. Savolainen, E. Ros

    We have found evidence for interaction between a standing and a traveling shock in the jet of the blazar CTA 102. Our result is based in the study of the spectral evolution of the turnover frequency-turnover flux density plane. The radio/mm light curves were taken during a major radio outburst in April 2006.

  60. David I. Stewart

    Let $G=G(K)$ be a simple algebraic group defined over an algebraically closed field $K$ of characteristic $p>0$. A subgroup $X$ of $G$ is said to be $G$-completely reducible if, whenever it is contained in a parabolic subgroup of $G$, it is contained in a Levi subgroup of that parabolic. A subgroup $X$ of $G$ is said to be $G$-irreducible if $X$ is in no par

  61. Juergen Sauter, Sebastian Wolf

    Circumstellar discs are expected to be the nursery of planets. Grain growth within such discs is the first step in the planet formation process in the core-accretion gas-capture scenario. We aim at providing selected criteria on observational quantities derived from multi-wavelength imaging observations that allow to identify dust grain growth and settling.

  62. Pedro Cabalar

    In this paper we consider a logical treatment for the ordered disjunction operator &#39;x&#39; introduced by Brewka, Niemelä and Syrjänen in their Logic Programs with Ordered Disjunctions (LPOD). LPODs are used to represent preferences in logic programming under the answer set semantics. Their semantics is defined by first translating the LPOD into a set of

  63. C. M. Fromm, E. Ros, T. Savolainen, M. Perucho

    The blazar CTA 102 underwent a major radio flare in April 2006. We used several 15 GHz VLBI observations from the MOJAVE program to investigate the influence of this extreme event on jet kinematics. The result of modeling and analysis lead to the suggestion of an interaction between traveling and standing shocks 0.2 mas away from the VLBI core.

  64. C. M. Fromm, E. Ros, T. Savolainen, A. P. Lobanov

    The radio light curve and spectral evolution of the blazar CTA 102 during its 2006 outburst can be rather well explained by the standard shock-in-jet model. The results of a pixel-to-pixel spectral analysis of multi-frequency VLBI images, together with kinematics derived from the MOJAVE survey lead to the picture of an over-pressured jet with respect to the

  65. A. T. Avelar, D. Bazeia, W. B. Cardoso

    In this paper we present analytical breather solutions of the three-dimensional nonlinear generalized Gross-Pitaevskii equation. We use an Ansatz to reduce the three-dimensional equation with space- and time-dependent coefficients into an one-dimensional equation with constant coefficients. The key point is to show that both the space- and time-dependent coe

  66. N. G. Fytas, A. Malakis

    We investigate, by means of extensive Monte Carlo simulations, the magnetic critical behavior of the three-dimensional bimodal random-field Ising model at the strong disorder regime. We present results in favor of the two-exponent scaling scenario, $\barη=2η$, where $η$ and $\barη$ are the critical exponents describing the power-law decay of the connected an

  67. Ariane Lançon

    The evolution of AGB stars is notoriously complex. The confrontation of AGB population models with observed stellar populations is a useful alternative to the detailed study of individual stars in efforts to converge towards a reliable evolution theory. I review here the impact of studies of star clusters on AGB models and AGB population synthesis, deliberat

  68. Jordi S. Andreu, Juan Camacho, Jordi Faraudo

    Experimental and simulation studies of superparamagnetic colloids in strong external fields have systematically shown an irreversible aggregation process in which chains of particles steadily grow and the average size increases with time as a power-law. Here we show, by employing Langevin dynamics simulations the existence of a different aggregation behavior

  69. N. Hollmann, Z. Hu, Hua Wu, M. Valldor

    CaBaFe4O7 is a mixed-valent transition metal oxide having both Fe2+ and Fe3+ ions in tetrahedral coordination. Here we characterize its magnetic properties by magnetization measurements and investigate its local electronic structure using soft x-ray absorption spectroscopy at the Fe L2,3 edges, in combination with multiplet cluster and spin-resolved band str

  70. J. R. Batley et al.

    A sample of 3120 $K^\pm\toπ^\pmμ^+μ^-$ decay candidates with $(3.3\pm0.7)%$ background contamination has been collected by the NA48/2 experiment at the CERN SPS, allowing a detailed study of the decay properties. The branching ratio was measured to be ${\rm BR}=(9.62\pm0.25)\times 10^{-8}$. The form factor $W(z)$, where $z=(M_{μμ}/M_K)^2$, was parameterized

  71. L. Moscadelli, R. Cesaroni, M. J. Rioja, R. Dodson

    IRAS 20126+4104 is one of the best candidates for a high-mass (proto)star surrounded by an accretion disk. Such a fact may be used to set constraints on theories of high-mass star formation, but requires confirmation that the mass and luminosity of IRAS 20126+4104 are indeed typical of a B0.5 star, which in turn requires an accurate estimate of the distance.

  72. S. Cavazzani, S. Ortolani, V. Zitelli, Y. Maruccia

    Comparing the number of clear nights (cloud free) available for astronomical observations is a critical task because it should be based on homogeneous methodologies. Current data are mainly based on different judgements based on observer logbooks or on different instruments. In this paper we present a new homogeneous methodology on very different astronomica

  73. Qing Lin, Bing He

    The authors call attention to a previous work [Qing Lin and Bing He, Phys. Rev. A 80, 042310 (2009)] on the realization of multi-qubit logic gates with controlled-path and merging gate. We supplement the work by showing how to efficiently build realistic quantum circuits in this approach and giving the guiding rules for the task.

  74. Alejandro Perez

    The study of rare B-decays at SuperB provides unique opportunities to understand the Standard Model and constrain new physics. It is discussed the new physics potential of the B -> K nu nu_bar and B -> K^{\ast} nu nu_bar system from the proposed SuperB experiment with 75ab-1 of data (5 nominal years of data taking).

  75. Dong-Jin Jang, A. B. Vorontsov, I. Vekhter, K. Gofryk

    We present low-temperature specific heat of the electron-doped Ba(Fe$_{0.9}$Co$_{0.1}$)$_{2}$As$_{2}$, which does not show any indication of an upturn down to 400 mK, the lowest measuring temperature. The lack of a Schottky-like feature at low temperatures or in magnetic fields up to 9 Tesla enables us to identify enhanced low-temperature quasiparticle excit

  76. Miloslav Znojil, Miloš Tater

    A new version of an elementary PT-symmetric square well quantum model is proposed in which a certain Hermiticity-violating end-point interaction leaves the spectrum real in a large domain of couplings $λ\in (-1,1)$. Within this interval we employ the usual coupling-independent operator P of parity and construct, in a systematic Runge-Kutta discrete approxima

  77. M. Malekjani, A. Khodam-Mohammadi, N. Nazari-pooya

    In this paper, the holographic dark energy model with new infrared cut-off proposed by Granda and Oliveros has been investigated in spatially non flat universe. The dependency of the evolution of equation of state, deceleration parameter and cosmological evolution of Hubble parameter on the parameters of new HDE model are calculated. Also, the statefinder pa

  78. Alexander Mustill, Mark Wyatt

    Mean motion resonances are a common feature of both our own Solar System and of extrasolar planetary systems. Bodies can be trapped in resonance when their orbital semi-major axes change, for instance when they migrate through a protoplanetary disc. We use a Hamiltonian model to thoroughly investigate the capture behaviour for first and second order resonanc

  79. Miloslav Znojil

    In an innovative inverse-problem construction the measured, experimental energies $E_1$, $E_2$, ...$E_N$ of a quantum bound-state system are assumed fitted by an N-plet of zeros of a classical orthogonal polynomial $f_N(E)$. We reconstruct the underlying Hamiltonian $H$ (in the most elementary nearest-neighbor-interaction form) and the underlying Hilbert spa

  80. D. Bulacu, S. Caenepeel

    Let $B$ be a bialgebra, and $A$ a left $B$-comodule algebra in a braided monoidal category $\Cc$, and assume that $A$ is also a coalgebra, with a not-necessarily associative or unital left $B$-action. Then we can define a right $A$-action on the tensor product of two relative Hopf modules, and this defines a monoidal structure on the category of relative Hop

  81. V. G. Ivanov, E. V. Miletsky

    Based on the extended Greenwich-NOAA/USAF catalogue of sunspot groups it is demonstrated that the parameters describing the latitudinal width of the sunspot generating zone (SGZ) are closely related to the current level of solar activity, and the growth of the activity leads to the expansion of SGZ. The ratio of the sunspot number to the width of SGZ shows s

  82. Davide R. Campagnari, Hugo Reinhardt

    A general method for treating non-Gaussian wave functionals in quantum field theory is presented and applied to the Hamiltonian approach to Yang-Mills theory in Coulomb gauge in order to include a three-gluon kernel in the exponential of the vacuum wave functional. The three-gluon vertex is calculated using the propagators found in the variational approach w

  83. Pegah Zolfaghari, Somayeh Zare, Behrouz Mirza

    Recently, Kawai, Parrondo, and Van den Broeck have related dissipation to time-reversal asymmetry. We generalized the result by considering a protocol where the physical system is driven away from an initial thermal equilibrium state with temperature $β_0$ to a final thermal equilibrium state at a different temperature. We illustrate the result using a model

  84. Michael Schmutz, Thomas Zürcher

    It is well known that any sufficiently regular one-dimensional payoff function has an explicit static hedge by bonds, forward contracts and lots of vanilla options. We show that the natural extension of the corresponding representation leads to a static hedge based on the same instruments along with traffic light options, which have recently been introduced

  85. Sara O. Case, Clinton H. Durney, Michel Pleimling, R. K. P. Zia

    Generalizing the cyclically competing three-species model (often referred to as the rock-paper-scissors game), we consider a simple system of population dynamics without spatial structures that involves four species. Unlike the previous model, the four form alliance pairs which resemble partnership in the game of Bridge. In a finite system with discrete stoc

  86. S. Geier, P. F. L. Maxted, R. Napiwotzki, R. H. Oestensen

    The project Massive Unseen Companions to Hot Faint Underluminous Stars from SDSS (MUCHFUSS) aims at finding hot subdwarf stars with massive compact companions like massive white dwarfs (M > 1.0 Msun), neutron stars or stellar mass black holes. The existence of such systems is predicted by binary evolution theory and recent discoveries indicate that they exis

  87. Seokhyun Yoon, Jun Heo

    Pair-wise Markov random fields (MRF) are considered for application to the development of low complexity, iterative MIMO detection. Specifically, we consider two types of MRF, namely, the fully-connected and ring-type. For the edge potentials, we use the bivariate Gaussian function obtained by marginalizing the posterior joint probability density under the G

  88. Hoavo Hova, Huanxiong Yang

    We propose a new fluid model of dark energy for $-1 \leq ω_{\text{eff}} \leq 0$ as an alternative to the generalized Chaplygin gas models. The energy density of dark energy fluid is severely suppressed during barotropic matter dominant epochs, and it dominates the universe evolution only for eras of small redshift. From the perspective of fundamental physics

  89. Panagiotis E. Theodorakis, Nikolaos G. Fytas

    Molecular dynamics simulations are used to study the phase behavior of linear multiblock copolymers with two types of monomers, A and B, where the length of the polymer blocks $N_{A}$ and $N_{B}$ ($N_{A}=N_{B}=N$), the number of the blocks $n_{A}$ and $n_{B}$ ($n_{A}=n_{B}=n$), and the solvent quality varies. The fraction $f$ of A-type monomers is kept const

  90. Miguel Martin, Javier Meri, Mikhail Popov

    We show that the absolute numerical index of the space $L_p(μ)$ is $p^{-1/p} q^{-1/q}$ (where $1/p+1/q=1$). In other words, we prove that $$ \sup\{\int |x|^{p-1}|Tx|\, dμ\, : \ x\in L_p(μ),\,\|x\|_p=1\} \,\geq \,p^{-\frac{1}{p}} q^{-\frac{1}{q}}\,\|T\| $$ for every $T\in \mathcal{L}(L_p(μ))$ and that this inequality is the best possible when the dimension of

  91. Xiao-Wu Chen

    For a weighted projective line, the stable category of its vector bundles modulo lines bundles has a natural triangulated structure. We prove that, for any positive integers $p, q, r$ and $r&#39;$ with $r&#39;\leq r$, there is an explicit recollement of the stable category of vector bundles on a weighted projective line of weight type $(p, q, r)$ relative to

  92. Jerome Faillettaz, Didier Sornette, Martin Funk

    A hanging glacier at the east face of Weisshorn (Switzerland) broke off in 2005. We were able to monitor and measure surface motion and icequake activity for 25 days up to three days prior to the break-off. The analysis of seismic waves generated by the glacier during the rupture maturation process revealed four types of precursory signals of the imminent ca

  93. Kathrin Maurischat

    We give a full set of Casimir operators for the symplectic group of arbitrary genus in terms of a basis chosen such that the action on representations of known $K$-type becomes transparent. We give examples for the latter.

  94. Matthew Tarbard

    Given a natural number $k \geq 2$, we construct a hereditarily indecomposable, $\mathscr{L}_{\infty}$ space, $X_k$ with dual isomorphic to $\ell_1$. We exhibit a non-compact, strictly singular operator $S$ on $X_k$, with the property that $S^k = 0$ and $S^j (0 \leq j \leq k-1)$ is not a compact perturbation of any linear combination of $S^l, l \neq j$. Moreo

  95. Marcelo F. Furtado, João Pablo P. Silva

    In this paper we are concerned with the number of nonnegative solutions of the elliptic system $$ {array}{ll} -Δu = Q_u(u,v) + 1/2{2^*} H_u(u,v),& {in} Ω,\vdois\ -Δv = Q_v(u,v) + 1/{2^*} H_v(u,v),& {in} Ω,\vdois\ u=v=0,& {on} \partialΩ. \leqno{(P)} $$ where $Ω\subset \mathbb{R}^N$ is a bounded smooth domain, $N \geq 3$, $2^*:=2N/(N-2)$ and $Q_u, H_u$ and $Q_

  96. Dmitry Semenov

    Protoplanetary disks (PPDs) surrounding young stars are short-lived (~0.3-10 Myr), compact (~10-1000 AU) rotating reservoirs of gas and dust. PPDs are believed to be birthplaces of planetary systems, where tiny grains are assembled into pebbles, then rocks, planetesimals, and eventually planets, asteroids, and comets. Strong variations of physical conditions

  97. Serge Cantat, Abdelghani Zeghib

    We classify compact Kähler manifolds $M$ of dimension $n\geq 3$ on which acts a lattice of an almost simple real Lie group of rank $\geq n-1$. This provides a new line in the so-called Zimmer program, and characterizes certain type of complex tori by a property of their automorphisms groups.

  98. Tomasz Bojdecki, Luis G. Gorostiza, Anna Talarczyk

    We study an infinite system of independent symmetric random walks on a hierarchical group, in particular, the c-random walks. Such walks are used, e.g., in population genetics. The number variance problem consists in investigating if the variance of the number of &#34;particles&#34; N_n(L) lying in the ball of radius L at a given time n remains bounded, or e

  99. F. Francica, F. Plastina, S. Maniscalco

    In this paper we study the possibility of modifying the dynamics of both quantum correlations, such as entanglement and discord, and classical correlations of an open bi-partite system by means of the quantum Zeno effect. We consider two qubits coupled to a common boson reservoir at zero temperature. This model describes, for example, two atoms interacting w

  100. Petr Kulish, Andrey Mudrov

    Transformation of operator algebras under Hopf algebra twist is studied. It is shown that that adjoint module algebras are stable under the twist. Applications to vector fields on non-commutative space-time are considered.