April 2010 arXiv papers — page 54

M. Trenti, M. Stiavelli, R. J. Bouwens, P. Oesch

The new Wide Field Camera 3/IR observations on the Hubble Ultra-Deep Field started investigating the properties of galaxies during the reionization epoch. To interpret these observations, we present a novel approach inspired by the conditional luminosity function method. We calibrate our model to observations at z=6 and assume a non-evolving galaxy luminosit

Soummya Kar, José M. F. Moura

The paper presents the gossip interactive Kalman filter (GIKF) for distributed Kalman filtering for networked systems and sensor networks, where inter-sensor communication and observations occur at the same time-scale. The communication among sensors is random; each sensor occasionally exchanges its filtering state information with a neighbor depending on th

F. Yusef-Zadeh, J. Miller-Jones, D. Roberts, M. Wardle

To understand the correlation and the radiation mechanism of flare emission in different wavelength bands, we have coordinated a number of telescopes to observe SgrA* simultaneously. We focus only on one aspect of the preliminary results of our multi-wavelength observing campaigns, namely, the short time scale variability of emission from SgrA* in near-IR, X

Aurelian Balan, C. Tycner, R. T. Zavala, J. A. Benson

High spatial resolution observations of the Hα-emitting wind structure associated with the Luminous Blue Variable star P Cygni were obtained with the Navy Prototype Optical Interferometer (NPOI). These observations represent the most comprehensive interferometric data set on P Cyg to date. We demonstrate how the apparent size of the Hα-emitting region of the

K. A. Matveev, A. V. Andreev, M. Pustilnik

Equilibration of a one-dimensional system of interacting electrons requires processes that change the numbers of left- and right-moving particles. At low temperatures such processes are strongly suppressed, resulting in slow relaxation towards equilibrium. We study this phenomenon in the case of spinless electrons with strong long-range repulsion, when the e

Graham Smith

Using the Perron method, we prove the existence of hypersurfaces of prescribed special Lagrangian curvature with prescribed boundary inside complete Riemannian manifolds of non-positive curvature.

M. Ignaccolo, P. Grigolini, B. J. West

We introduce a new method for detecting scaling in time series. The method uses the properties of the probability flux for stochastic self-affine processes and is called the probability flux analysis (PFA). The advantages of this method are: 1) it is independent of the finiteness of the moments of the self-affine process; 2) it does not require a binning pro

Harry Yeh, Wenwen Li, Yuji Kodama

Reflection of an obliquely incident solitary wave onto a vertical wall is studied analytically and experimentally. We use the Kadomtsev-Petviashivili (KP) equation to analyze the evolution and its asymptotic state. Laboratory experiments are performed using the laser induced fluorescent (LIF) technique, and detailed features and amplifications at the wall ar

Marcus Freitag, Hsin-Ying Chiu, Mathias Steiner, Vasili Perebeinos

Graphene is a 2-dimensional material with high carrier mobility and thermal conductivity, suitable for high-speed electronics. Conduction and valence bands touch at the Dirac point. The absorptivity of single-layer graphene is 2.3%, nearly independent of wavelength. Here we investigate the thermal radiation from biased graphene transistors. We find that the

Tuvi Etzion, Alexander Vardy, Eitan Yaakobi

Several new applications and a number of new mathematical techniques have increased the research on error-correcting codes in the Lee metric in the last decade. In this work we consider several coding problems and constructions of error-correcting codes in the Lee metric. First, we consider constructions of dense error-correcting codes in relatively small di

Jesse Liptrap

We show that the ring of translation invariant symmetric polynomials in n variables is isomorphic to the full polynomial ring in n-1 variables, in characteristic 0. We disprove a conjecture of Haldane regarding the structure of such polynomials. Our motivation is the fractional quantum Hall effect, where translation invariant (anti)symmetric complex n-variat

G. Bono, F. Caputo, M. Marconi, I. Musella

We present an investigation of Cepheid distances using theory and observations. Cepheid models indicate that the slope of the Period-Luminosity (P-L) relation covering the entire period range (0.40<= logP <=2.0) becomes steeper when moving from optical to NIR bands, and that the metallicity dependence of the slope decreases from the B- to the K-band. We esti

Matthew A. Lohr, Ahmed M. Alsayed, Bryan G. Chen, Zexin Zhang

The phase behavior of helical packings of thermoresponsive microspheres inside glass capillaries is studied as a function of volume fraction. Stable packings with long-range orientational order appear to evolve abruptly to disordered states as particle volume fraction is reduced, consistent with recent hard sphere simulations. We quantify this transition usi

Takaaki Sogo, Gerd Röpke, Peter Schuck

The theory for condensation of higher fermionic clusters is developed. Fully selfconsistent nonlinear equations for the quartet order parameter in strongly coupled fermionic systems are established and solved. The breakdown of the quasiparticle picture is pointed out. Derivation of numerically tractable approximation is described. The momentum projected fact

A. Cervera, A. Laing, J. Martin-Albo, F. J. P. Soler

A Neutrino Factory producing an intense beam composed of nu_e(nubar_e) and nubar_mu(nu_mu) from muon decays has been shown to have the greatest sensitivity to the two currently unmeasured neutrino mixing parameters, theta_13 and delta_CP . Using the `wrong-sign muon&#39; signal to measure nu_e to nu_mu(nubar_e to nubar_mu) oscillations in a 50 ktonne Magneti

Sébastien Boyaval, Claude Le Bris, Tony Lelièvre, Yvon Maday

We report here on the recent application of a now classical general reduction technique, the Reduced-Basis approach initiated in [C. Prud&#39;homme, D. Rovas, K. Veroy, Y. Maday, A. T. Patera, and G. Turinici. Reliable real-time solution of parametrized partial differential equations: Reduced-basis output bounds methods. Journal of Fluids Engineering, 124(1)

A. M. Makarieva, V. G. Gorshkov, D. Sheil, A. D. Nobre

Phase transitions of atmospheric water play a ubiquitous role in the Earth&#39;s climate system, but their direct impact on atmospheric dynamics has escaped wide attention. Here we examine and advance a theory as to how condensation influences atmospheric pressure through the mass removal of water from the gas phase with a simultaneous account of the latent

J. Ambjorn, J. Jurkiewicz, R. Loll

Quantum Gravity by Causal Dynamical Triangulation has over the last few years emerged as a serious contender for a nonperturbative description of the theory. It is a nonperturbative implementation of the sum-over-histories, which relies on few ingredients and initial assumptions, has few free parameters and - crucially - is amenable to numerical simulations.

Srivathsan Srinivasagopalan, Costas Busch, S. S. Iyengar

We consider the problem of constructing a single spanning tree for the single-source buy-at-bulk network design problem for doubling-dimension graphs. We compute a spanning tree to route a set of demands (or data) along a graph to or from a designated root node. The demands could be aggregated at (or symmetrically distributed to) intermediate nodes where the

Xi Chen, Jia-Wei Tao, Yue Ban

We investigate the Goos-Hänchen-like shifts for Dirac fermions in transmission through a monolayer graphene barrier. The lateral shifts, as the functions of the barrier&#39;s width and the incidence angle, can be negative and positive in Klein tunneling and classical motion, respectively. Due to their relations to the transmission gap, the lateral shifts can

Chang Q Sun, Yanguang Nie, Jisheng Pan, Weitao Zheng

We present a simple approach for purifying graphite surface and vacancy states using an angle-resolved x-ray photoelectron residual spectroscopy (XPS). Complementing the discoveries of Ugeda et al [Phys Rev Lett 104, 096804 (2010)], outcomes conform the BOLS theory [Sun, Prog Solid State Chem 35, 1-159 (2007)] expectation and the recent findings that the sho

A. A. Abdo

This paper presents light curves and the first systematic characterization of variability of the 106 objects in the Fermi Large Area Telescope (LAT) Bright AGN Sample (LBAS). Weekly light curves obtained during the first 11 months of survey (August 04, 2008 - July 04, 2009), are tested for variability, and their properties are quantified through autocorrelat

Ion Patrascu, Florentin Smarandache

In this paper we prove that if $P_1, P_2$ are isogonal points in the triangle $ABC$, and if $A_1B_1C_1$ and $A_2B_2C_2$ are their corresponding pedal triangles such that the triangles $ABC$ and $A_1B_1C_1$ are homological (the lines $AA_1, BB_1, CC_1$ are concurrent), then the triangles $ABC$ and $A_2B_2C_2$ are also homological.

Vital LeDez, Hamou Sadat

A coherent definition of the reflection and transmission factors at a plane interface separating two uniaxial crystals is proposed, from the photons impulsion-energy 4-vectors conservation. This definition, different from the classical electromagnetic one, is compatible with the completely resolved extended Fermat&#39;s principle of the geometric optics for

James Kirkpatrick

In an organic blend the vibrational normal mode excited by exciton splitting is the same as the one coupled to charge hopping. Excess driving force for exciton splitting can therefore aid charge transfer, if vibrational relaxation is slow compared to charge transfer. A model is developed that takes this into account and hence explains the experimentally obse

Kai Yi

The Tevatron experiments have each accumulated about 6 \ifb good data since the start of RUN II. This large dataset provided good opportunities for meson spectroscopy studies at the Tevatron. This article will cover the recent new $Υ(nS)$ polarization studies as well as exotic meson spectroscopy studies.

Pierluigi Colli, Philippe Laurençot

The well-posedness of a phase-field approximation to the Willmore flow with volume constraint is established. The existence proof relies on the underlying gradient flow structure of the problem: the time discrete approximation is solved by a variational minimization principle.

Harald Lück, Christopf Affeldt, Jerome Degallaix, Andreas Freise

The German / British gravitational wave detector GEO 600 is in the process of being upgraded. The upgrading process of GEO 600, called GEO-HF, will concentrate on the improvement of the sensitivity for high frequency signals and the demonstration of advanced technologies. In the years 2009 to 2011 the detector will undergo a series of upgrade steps, which ar

Harald Lueck

This article gives a short overview of the status of the British/German gravitational wave detector GEO 600 and the upgrades planned within 2010 and 2011

R. Schützhold, G. Gnanapragasam

We study the possibility of suppressing three-body losses in atomic Bose-Einstein condensates via the quantum Zeno effect, which means the delay of quantum evolution by frequent measurements. It turns out that this requires very fast measurements with the rate being determined by the spatial structure of the three-body form factor, i.e., the point interactio

Ning Lu, Ying Huang, Haibei Li, Zhenyu Li

Nuclear magnetic resonance (NMR) has been widely used in the graphene oxide (GO) structure study. However, the detailed relationship between its spectroscopic features and the GO structural configuration has remained elusive. Based on first principles $^{13}$C chemical shift calculations using the gauge including projector augmented waves (GIPAW) method, we

B. -Wolfgang Schulze, Andrea Volpato

We study pseudo-differential operators on a wedge with continuous and variable discrete branching asymptotics.

Masato Onodera, Nobuo Arimoto, Emanuele Daddi, Alvio Renzini

Results are presented from NIR spectroscopy of a sample of BzK-selected, massive star-forming galaxies (sBzKs) at 1.5<z<2.3 that were obtained with OHS/CISCO at Subaru and with SINFONI at VLT. Among the 28 sBzKs observed, Ha emission was detected in 14 objects, and for 11 of them the [NII]6583 was also measured. Multiwavelength photometry was also used to de

M. Kuassivi

I investigate the effect of the radiation drag force on a star moving relative to the Cosmic Microwave Background (CMB) at z = 0. As expected, the perturbation is extremely small and has no observable consequences on orbital motions of stars within a galaxy or on orbital motions of galaxies within a cluster. The energy dissipated by cubic meter in a galaxy v

Ethan Cotterill

This paper is a sequel to \cite{C}, in which the author studies secant planes to linear series on a curve that is general in moduli. In that paper, the author proves that a general curve has no linear series with exceptional secant planes, in a very precise sense. Consequently, it makes sense to study effective divisors on $\ov{\mc{M}}_g$ associated to curve

Alessandro Drago, Andrea Lavagno

We discuss new limits on masses and radii of compact stars and we conclude that they can be interpreted as an indication of the existence of two classes of stars: &#34;normal&#34; compact stars and &#34;ultra-compact&#34; stars. We estimate the critical mass at which the first configuration collapses into the second.

Ethan Akin, Joseph Auslander

While compactness is an essential assumption for many results in dynamical systems theory, for many applications the state space is only locally compact. Here we provide a general theory for compactifying such systems, i.e. embedding them as invariant open subsets of compact systems. In the process we don&#39;t want to introduce recurrence which was not ther

E. Feschet-Chassot, V. Raspal, O. K. Awitor, F. Bonnemoy

In this work, we have developed economic process to elaborate scalable titanium dioxide nanotube layers which show a tunable functionality. The titanium dioxide nanotube layers was prepared by electrochemical anodization of Ti foil in 0.4 wt% hydrofluoric acid solution. The nanotube layers structure and morphology were characterized using x-ray diffraction a

A. Piccolroaz, G. Mishuris, A. B. Movchan

We consider the perturbation problem of a Mode III interfacial crack. The perturbation is of geometrical type and can be both perturbation of the crack faces and perturbation of the interface, which can deviate from the initial straight line configuration. Asymptotic formulae are derived for the first-order perturbation of the stress intensity factor. It is

Marta Aparicio Arroyo, Oscar Garcia-Prada

Using the Morse-theoretic methods introduced by Hitchin, we prove that the moduli space of $\SO_0(1,n)$-Higgs bundles when $n$ is odd has two connected components.

J. Sosnowski

New results of the investigations critical current problems in the high temperature oxide superconductors are presented, basing on an analysis of the flux pinning on nano-sized centers. New model of the interaction pancake vortices with the nano-sized centers is proposed, while comparison of obtained results with others pinning forces approaches presented. T

Colin Guillarmou, Mikko Salo, Leo Tzou

On a fixed Riemann surface $(M_0,g_0)$ with $N$ Euclidean ends and genus $g$, we show that, under a topological condition, the scattering matrix $S_V(\la)$ at frequency $\la > 0$ for the operator $Δ+V$ determines the potential $V$ if $V\in C^{1,α}(M_0)\cap e^{-γd(\cdot,z_0)^j}L^\infty(M_0)$ for all $γ>0$ and for some $j\in\{1,2\}$, where $d(z,z_0)$ denotes t

Salah Eddine Elayoubi, Eitan Altman, Majed Haddad, Zwi Altman

The area of networking games has had a growing impact on wireless networks. This reflects the recognition in the important scaling advantages that the service providers can benefit from by increasing the autonomy of mobiles in decision making. This may however result in inefficiencies that are inherent to equilibria in non-cooperative games. Due to the conce

M. Robert-de-Saint-Vincent, J. -P. Brantut, B. Allard, T. Plisson

We study the horizontal expansion of vertically confined ultra-cold atoms in the presence of disorder. Vertical confinement allows us to realize a situation with a few coupled harmonic oscillator quantum states. The disordered potential is created by an optical speckle at an angle of 30° with respect to the horizontal plane, resulting in an effective anisotr

Tomohito Maeda, Kenji Yamada, Masuho Oda, Shin Ishida

In order to classify the charmed-strange mesons, including puzzling D_{s0}^{*}(2317) and D_{s1}(2460), and recently observed D_{s1}^{*}(2710) and D_{sJ}^{*}(2860), we employ the U~(12)*O(3,1) level-classification scheme of hadrons proposed and developed by us in recent years. The scheme has a new degree of freedom, SU(2)_ρ, which leads to a number of extra s

R. Lazauskas, C. Volpe

In the future several Spallation Source facilities will be available worldwide. Spallation Sources produce large amount of neutrinos from decay-at-rest muons and thus can be well adapted to accommodate state-of-the-art neutrino experiments. In this paper low energy neutrino scattering experiments that can be performed at such facilities are reviewed. Estimat

J. J. Alonso, B. Allés

By tempered Monte Carlo simulations, we study 2D site-diluted dipolar Ising systems. Dipoles are randomly placed on a fraction x of all L^2 sites in a square lattice, and point along a common crystalline axis. For x_c< x<=1, where x_c = 0.79(5), we find an antiferromagnetic phase below a temperature which vanishes as x approaches x_c from above. At lower val

H. Meheut, F. Casse, P. Varniere, M. Tagger

Context. The formation of vortices in accretion disks is of high interest in various astrophysical contexts, in particular for planet formation or in the disks of compact objects. But despite numerous attempts it has thus far not been possible to produce strong vortices in fully three-dimensional simulations of disks. Aims. The aim of this paper is to presen

Giampaolo Cicogna

We consider symmetries and perturbed symmetries of canonical Hamiltonian equations of motion. Specifically we consider the case in which the Hamiltonian equations exhibit a Lambda symmetry under some Lie point vector field. After a brief survey of the relationships between standard symmetries and the existence of first integrals, we recall the definition and

Shaohua Zhang, Ting-Gui Wang, Huiyuan Wang, Hongyan Zhou

We present a sample of 68 low-z MgII low-ionization broad absorption-line (loBAL) quasars. The sample is uniformly selected from the SDSS5 according to the following criteria: (1) 0.4<z<0.8, (2) median S/N>7, and (3) MgII absorption-line width > 1600 \kms. The last criterion is a trade-off between the completeness and consistency with respect to the canonica

K. A. Ispirian, M. K. Ispiryan

A method is suggested to produce, with the help of colliding laser photons with bunches of relativistic ions having two energy levels, both intense beams of monochromatic polarized X-ray fluorescence photons and significant number of X-ray entangled photons, via double Doppler transformation. Nonlinear susceptibility of the ions, the cross section and the ra

Jacek Brodzki, Graham A. Niblo, Piotr Nowak, Nick Wright

We show that topological amenability of an action of a countable discrete group on a compact space is equivalent to the existence of an invariant mean for the action. We prove also that this is equivalent to vanishing of bounded cohomology for a class of Banach G-modules associated to the action, as well as to vanishing of a specific cohomology class. In the

Olgur Celikbas, Hailong Dao

Let $R$ be a local ring, and let $M$ and $N$ be finitely generated $R$-modules such that $M$ has finite complete intersection dimension. In this paper we define and study, under certain conditions, a pairing using the modules $\Ext_R^i(M,N)$ which generalizes Buchweitz&#39;s notion of the Herbrand diference. We exploit this pairing to examine the number of c

Sergei A. Grebenev

We review X-ray properties of the Supergiant Fast X-ray Transients following from their observations with INTEGRAL and show that a compact object in these systems is a neutron star with strong magnetic field accreting from the stellar wind of a donor star. We show that presence of a centrifugal barrier at the magnetospheric boundary of the neutron star may b

Ken&#39;ichiro Nakazato, Kohsuke Sumiyoshi, Hideyuki Suzuki, Shoichi Yamada

The detection of neutrinos from massive stellar collapses can teach us a lot not only about source objects but also about microphysics working deep inside them. In this study we discuss quantitatively the possibility to extract information on the properties of dense and hot hadronic matter from neutrino signals coming out of black-hole-forming collapses of n

S. Brendle

Let C be a cone in the space of algebraic curvature tensors. Moreover, let (M,g) be a compact Einstein manifold with the property that the curvature tensor of (M,g) lies in the cone C at each point on M. We show that (M,g) has constant sectional curvature if the cone C satisfies certain structure conditions.

Mihail Alfimov

Cherenkov radiation in uniformly moving homogenous isotropic medium without dispersion is studied. Formula for the spectrum of Cherenkov radiation of fermion was derived for the case when the speed of the medium is less than the speed of light in this medium at rest. The properties of Cherenkov spectrum are investigated.

Bernhard Kramer, Angus MacKinnon, Tomi Ohtsuki, Keith Slevin

This chapter describes the progress made during the past three decades in the finite size scaling analysis of the critical phenomena of the Anderson transition. The scaling theory of localisation and the Anderson model of localisation are briefly sketched. The finite size scaling method is described. Recent results for the critical exponents of the different

E. Arias, N. F. Svaiter, G. Menezes

For spatially bounded free fields, the Bekenstein bound states that the specific entropy satisfies the inequality $\frac{S}{E} \leq 2 πR$, where $R$ stands for the radius of the smallest sphere that circumscribes the system. The validity of the Bekenstein bound on the specific entropy in the asymptotically free side of the Euclidean $(λ\,ϕ^{\,4})_{d}$ self-i

Hyunbae Park, Juhan Kim, Changbom Park

We extend the concept of galaxy environment from the local galaxy number density to the gravitational potential and its functions like the shear tensor. For this purpose we examine whether or not one can make an accurate estimation of the gravitational potential from an observational sample which is finite in volume, biased due to galaxy biasing, and subject

J. McCarty, I. Y. Lyubimov, M. G. Guenza

Mesoscopic molecular dynamics simulations are used to determine the large scale structure of several binary polymer mixtures of various chemical architecture, concentration, and thermodynamic conditions. By implementing an analytical formalism, which is based on the solution to the Ornstein-Zernike equation, each polymer chain is mapped onto the level of a s

Wenchang Xiang

We study the effect of gluon number fluctuations (Pomeron loops) on the impact parameter behavior of the scattering amplitude in the fixed coupling case. We demonstrate that the dipole-hadron cross-section computed from gluon number fluctuations saturates the Froissart bound and the growth of the radius of the black disk with rapidity is enhanced by an addit

S. Buitink, O. Scholten, J. Bacelar, R. Braun

Ultra-high energy (UHE) neutrinos and cosmic rays initiate particle cascades underneath the Moon&#39;s surface. These cascades have a negative charge excess and radiate Cherenkov radio emission in a process known as the Askaryan effect. The optimal frequency window for observation of these pulses with radio telescopes on the Earth is around 150 MHz. By obser

Wenchang Xiang

Pomeron loop effects (gluon number fluctuations) on deep inelastic scattering (DIS) in the fixed coupling case are studied. We show that the description of the HERA data for the inclusive structure function $F_2(x,Q^2)$ for $x\leq10^{-2}$ and $0.045\leq Q^2\leq 45GeV^2$ is improved once pomeron loop effects are included.

Yi Wang

In this paper, we obtain the isoperimetric inequality on conformally flat manifold with finite total $Q$-curvature. This is a higher dimensional analogue of Li and Tam&#39;s result \cite{L-T} on surfaces with finite total Gaussian curvature. The main step in the proof is based on the construction of a quasiconformal map whose Jacobian is suitably bounded.

Jeffrey N. Cuzzi, Robert C. Hogan, William F. Bottke

Our goal is to understand primary accretion of the first planetesimals. The primitive meteorite record suggests that sizeable planetesimals formed in the asteroid belt over a period longer than a million years, each composed entirely of an unusual, but homogeneous, mixture of mm-size particles. We sketch a scenario in which primary accretion of 10-100km size

Amine Laourine, Aaron B. Wagner

Providing security guarantees for wireless communication is critically important for today&#39;s applications. While previous work in this area has concentrated on radio frequency (RF) channels, providing security guarantees for RF channels is inherently difficult because they are prone to rapid variations due small scale fading. Wireless optical communicati

Jonas de Woul, Jens Hoppe, Douglas Lundholm, Martin Sundin

A dynamical symmetry for supersymmetric extended objects is given.

J. Benlliure, H. Alvarez-Pol, T. Kurtukian-Nieto, K. -H. Schmidt

The existence of nuclei with exotic combinations of protons and neutrons provides fundamental information on the forces acting between nucleons. The maximum number of neutrons a given number of protons can bind, neutron drip line1, is only known for the lightest chemical elements, up to oxygen. For heavier elements, the larger its atomic number, the farther

Vincenzo Pellegrini, Luca Rose, Mario Di Dio

Since J. Mitola&#39;s work in 1992, Software Defined Radios (SDRs) have been quite a hot topic in wireless systems research. Though many notable achievements were reported in the field, the scarcity of computational power on general purpose CPUs has always constrained their wide adoption in production environments. If conveniently applied within an SDR conte

Alin Ciuperca, George A. Elliott, Luis Santiago

The class of separable C*-algebras which can be written as inductive limits of continuous-trace C*-algebras with spectrum homeomorphic to a disjoint union of trees and trees with a point removed is classified by the Cuntz semigroup.

Jeremy L. Marzuola, Gideon Simpson

In this work, we study the spectral properties of matrix Hamiltonians generated by linearizing the nonlinear Schrödinger equation about soliton solutions. By a numerically assisted proof, we show that there are no embedded eigenvalues for the three dimensional cubic equation. Though we focus on a proof of the 3d cubic problem, this work presents a new algori

B. J. Ramshaw, Baptiste Vignolle, James Day, Ruixing Liang

Measurements of quantum oscillations in the cuprate superconductors afford a new opportunity to assess the extent to which the electronic properties of these materials yield to a description rooted in Fermi liquid theory. However, such an analysis is hampered by the small number of oscillatory periods observed. Here we employ a genetic algorithm to globally

Ishwaree P Neupane

Generic cosmological models derived from higher dimensional theories with warped extra dimensions have a nonzero cosmological constant-like term induced on the 3+1 space-time, or a physical 3-brane. In the scenario where this 3+1 space-time is an inflating de Sitter &#34;brane&#34; embedded in a higher-dimensional space-time, described by warped geometry, th

Gergely Harcos, Gyula Károlyi, Géza Kós

Based on the recent work of Arsovski, we confirm a conjecture of Feng, Sun, and Xiang, and we give a shortened proof of Snevily&#39;s conjecture.

Jong-Hak Woo, Tommaso Treu, Aaron J. Barth, Shelley A. Wright

(Abridged) To investigate the black hole mass (MBH) vs. stellar velocity dispersion relation of active galaxies, we measured the velocity dispersions of a sample of local Seyfert 1 galaxies, for which we have recently determined MBH using reverberation mapping. For most objects, velocity dispersions were measured from high S/N ratio optical spectra centered

Tarcísio N. Teles, Yan Levin, Renato Pakter, Felipe B. Rizzato

We study, using both theory and molecular dynamics simulations, the relaxation dynamics of a microcanonical two dimensional self-gravitating system. After a sufficiently large time, a gravitational cluster of N particles relaxes to the Maxwell-Boltzmann distribution. The time to reach the thermodynamic equilibrium, however, scales with the number of particle

Oscar García-Prada, André Oliveira

Using Morse-theoretic techniques, we show that the moduli space of U*(2n)-Higgs bundles over a compact Riemann surface is connected.

J. E. Strapasson, S. I. R. Costa, M. M. S. Alves

The genus graphs have been studied by many authors, but just a few results concerning in special cases: Planar, Toroidal, Complete, Bipartite and Cartesian Product of Bipartite. We present here a derive general lower bound for the genus of a abelian Cayley graph and construct a family of circulant graphs which reach this bound.

Clément de Seguins Pazzis

Let K denote a field. Given an arbitrary linear subspace V of M_n(K) of codimension lesser than n-1, a classical result states that V generates the K-algebra M_n(K). Here, we strengthen this in three ways: we show that M_n(K) is spanned by the products of the form AB with A and B in V; we prove that every matrix in M_n(K) can be decomposed into a product of

The BaBar Collaboration, P. del Amo Sanchez

We present measurements of B-meson decays to the final states eta&#39;rho, eta&#39;f0, and eta&#39;K*, where K* stands for a vector, scalar, or tensor strange meson. We observe a significant signal or evidence for eta&#39;rho+ and all the eta&#39;K* channels. We also measure, where applicable, the charge asymmetries, finding results consistent with no direct

Giorgio Torrieri, Jorge Noronha

We demonstrate that a Quark-Gluon Plasma (QGP) with a dilute admixture of heavy quarks has, in general, a lower speed of sound than a &#34;pure&#34; QGP without effects from heavy flavors. The change in the speed of sound is sensitive to the details of the theory, making the hydrodynamic response to &#34;flavoring&#34; a sensitive probe of the underlying mic

Yuzo Maruyama, William E. Strawderman

We consider the problem of estimating the error variance in a general linear model when the error distribution is assumed to be spherically symmetric, but not necessary Gaussian. In particular we study the case of a scale mixture of Gaussians including the particularly important case of the multivariate-t distribution. Under Stein&#39;s loss, we construct a

Juan Rivera-Letelier, Weixiao Shen

For a real or complex one-dimensional map satisfying a weak hyperbolicity assumption, we study the existence and statistical properties of physical measures, with respect to geometric reference measures. We also study geometric properties of these measures.

G. Shen, C. J. Horowitz, S. Teige

We calculate the equation of state (EoS) of dense matter, using a relativistic mean field (RMF) model with a density dependent coupling that is a slightly modified form of the original NL3 interaction. For nonuniform nuclear matter we approximate the unit lattice as a spherical Wigner-Seitz cell, wherein the meson mean fields and nucleon Dirac wave functions

Bruce N. Miller, Jean-Louis Rouet

Concentrations of matter, such as galaxies and galactic clusters, originated as very small density fluctuations in the early universe. The existence of galaxy clusters and super-clusters suggests that a natural scale for the matter distribution may not exist. A point of controversy is whether the distribution is fractal and, if so, over what range of scales.

Johannes M. Henn, Jan Plefka, Konstantin Wiegandt

We study light-like polygonal Wilson loops in three-dimensional Chern-Simons and ABJM theory to two-loop order. For both theories we demonstrate that the one-loop contribution to these correlators cancels. For pure Chern-Simons, we find that specific UV divergences arise from diagrams involving two cusps, implying the loss of finiteness and topological invar

Khalid Bou-Rabee, Brandon Seward

A residually nilpotent group is \emph{$k$-parafree} if all of its lower central series quotients match those of a free group of rank $k$. Magnus proved that $k$-parafree groups of rank $k$ are themselves free. In this note we mimic this theory with finite extensions of free groups, with an emphasis on free products of the cyclic group $C_p$, for $p$ an odd p

M. Cappetta, V. D&#39;Odorico, S. Cristiani, F. Saitta

We study the three-dimensional distribution of matter at z~2 using high resolution spectra of QSO pairs and simulated spectra drawn from cosmological hydro-dynamical simulations. We present a sample of 15 QSOs, corresponding to 21 baselines of angular separations evenly distributed between ~1 and 14 arcmin, observed with the Ultraviolet and Visual Echelle Sp

Waldo Arriagada-Silva

In this paper we give a geometric description of the foliation of a generic real analytic family unfolding a real analytic vector field with a weak focus at the origin, and show that two such families are orbitally analytically equivalent if and only if the families of diffeomorphisms unfolding the complexified Poincaré map of the singularities are conjugate

Matthew Daws

A result of Gilbert shows that every completely bounded multiplier $f$ of the Fourier algebra $A(G)$ arises from a pair of bounded continuous maps $α,β:G \rightarrow K$, where $K$ is a Hilbert space, and $f(s^{-1}t) = (β(t)|α(s))$ for all $s,t\in G$. We recast this in terms of adjointable operators acting between certain Hilbert C$^*$-modules, and show that

Alexander M. Blokh, Robbert J. Fokkink, John C. Mayer, Lex G. Oversteegen

We present proofs of basic results, including those developed by Harold Bell, for the plane fixed point problem: does every map of a non-separating plane continuum have a fixed point? Some of these results had been announced much earlier by Bell but without accessible proofs. We define the concept of the variation of a map on a simple closed curve and relate

Antti J. Niemi, Sergey Slizovskiy

We inquire whether a resolution to the electroweak hierarchy problem could reside in symmetries that relate the bosonic Weinberg-Salam Lagrangian with a higher dimensional generally covariant theory. For this we consider a three-brane that moves under the influence of a seven dimensional pure Hilbert Einstein-like generally covariant theory. We introduce a c

Boaz Tsaban, Lyubomyr Zdomskyy

A classical theorem of Hurewicz characterizes spaces with the Hurewicz covering property as those having bounded continuous images in the Baire space. We give a similar characterization for spaces X which have the Hurewicz property hereditarily. We proceed to consider the class of Arhangel&#39;skii alpha_1 spaces, for which every sheaf at a point can be amal

Oliver Johnson, Matthew Aldridge, Robert Piechocki

Ergodic interference alignment, as introduced by Nazer et al (NGJV), is a technique that allows high-rate communication in n-user interference networks with fast fading. It works by splitting communication across a pair of fading matrices. However, it comes with the overhead of a long time delay until matchable matrices occur: the delay is q^n^2 for field si

Nicolas Monod

We point out a simple characterisation of topological amenability in terms of bounded cohomology, following Johnson&#39;s reformulation of amenability.

Dara P. S. McCutcheon, Ahsan Nazir, Sougato Bose, Andrew J. Fisher

Using a variational approach we investigate the delocalized to localized crossover in the ground state of an Ohmic two-impurity spin-boson model, describing two otherwise non-interacting spins coupled to a common bosonic environment. We show that a competition between an environment-induced Ising spin interaction and externally applied fields leads to variat

A. S. Holevo

We give a mathematical formulation for the Choi-Jamiolkowski (CJ) correspondence in the infinite-dimensional case in the form close to one used in quantum information theory. We show that there is no need to use a limiting procedure to define &#34;unnormalized maximally entangled state&#34; and the corresponding analog of the Choi matrix since they can be de

Maxim Kharitonov

We develop a theory of the correlated magnetically ordered insulating state at the edge of a two-dimensional topological insulator. We demonstrate that the gapped spin-polarized state, induced by the application of the magnetic field $B$, is naturally facilitated by electron interactions, which drive the critical easy-plane ferromagnetic correlations in the

Borivoje Dakic, Vlatko Vedral, Caslav Brukner

Quantum discord characterizes &#34;non-classicality&#34; of correlations in quantum mechanics. It has been proposed as the key resource present in certain quantum communication tasks and quantum computational models without containing much entanglement. We obtain a necessary and sufficient condition for the existence of non-zero quantum discord for any dimen