January 2010 arXiv papers — page 12
Showing 1,101–1,200 of 5,448 papers
Thomas Bäckdahl, Juan A. Valiente Kroon
A geometrical invariant for regular asymptotically Euclidean data for the vacuum Einstein field equations is constructed. This invariant vanishes if and only if the data correspond to a slice of the Kerr black hole spacetime --thus, it provides a measure of the non-Kerr-like behavior of generic data. In order to proceed with the construction of the geometric
Classification of Pseudo-Riemannian submersions with totally geodesic fibres from pseudo-hyperbolic spaces
math.DGGabriel Baditoiu
We classify pseudo-Riemannian submersions with connected totally geodesic fibres from a real pseudo-hyperbolic space onto a pseudo-Riemannian manifold. Also, we obtain the classification of the pseudo-Riemannian submersions with (para-)complex connected totally geodesic fibres from a (para-)complex pseudo-hyperbolic space onto a pseudo-Riemannian manifold.
Charles F. Dunkl
Polynomials with values in an irreducible module of the symmetric group can be given the structure of a module for the rational Cherednik algebra, called a standard module. This algebra has one free parameter and is generated by differential-difference ("Dunkl") operators, multiplication by coordinate functions and the group algebra. By specializing
Victor Gerasimov
A continuous equivariant map from the Floyd boundary of a relatively hyperbolic group (RHG for short) to its Bowditch boundary is constructed. Such a map is unique unless the group is two-ended. In order to optimize the proof and the usage of the map theorem we propose two new definitions of relative hyperbolicity equivalent to the other known definitions. I
E. Martin-Martinez, J. Leon
We disclose the behaviour of quantum and classical correlations among all the different spatial-temporal regions of a space-time with an event horizon, comparing fermionic with bosonic fields. We show the emergence of conservation laws for entanglement and classical correlations, pointing out the crucial role that statistics plays in the information exchange
Search for Higgs boson production in dilepton and missing energy final states with 5.4 fb-1 of p-pbar collisions at sqrt(s) =1.96 TeV
hep-exThe D0 Collaboration
A search for the standard model Higgs boson is presented using events with two charged leptons and large missing transverse energy selected from 5.4 fb-1 of integrated luminosity in p-pbar collisions at sqrt(s)=1.96 TeV collected with the D0 detector at the Fermilab Tevatron Collider. No significant excess of events above background predictions is found, and
Bernard J. T. Jones, Rien van de Weygaert, Miguel A. Aragon-Calvo
We search for and find fossil evidence that the distribution of the spin axes of galaxies in cosmic web filaments relative to their host filaments are not randomly distributed. This would indicate that the action of large scale tidal torques effected the alignments of galaxies located in cosmic filaments. To this end, we constructed a catalogue of clean fila
M. Zuin, A. Carati, M. Marino, E. Martines
Fusion research on magnetic confinement is confronted with a severe problem concerning the electron densities ne to be used in fusion devices. Indeed, high densities are mandatory for obtaining large efficiencies, whereas it is empirically found that catastrophic disruptive events occur for densities exceeding a maximal one n^M_e. On the other hand, despite
Ferroelectric hydration shells around proteins: Electrostatics of the protein/water interface
physics.bio-phDavid N. LeBard, Dmitry V. Matyushov
Numerical simulations of hydrated proteins show that protein hydration shells are polarized into a ferroelectric cluster with a large magnitude of its average dipole moment. The emergence of this new mesophase dramatically alters the statistics of electrostatic fluctuations at the protein/water interface. The linear-response relation between the average elec
Christine Lescop
Let M be a closed oriented 3-manifold with first Betti number one. Its equivariant linking pairing may be seen as a two-dimensional cohomology class in an appropriate infinite cyclic covering of the configuration space of ordered pairs of distinct points of M. We show how to define the equivariant cube Q(M,K) of this Blanchfield pairing with respect to a fra
Frédérique Bassino, Armando Martino, Cyril Nicaud, Enric Ventura
The usual way to investigate the statistical properties of finitely generated subgroups of free groups, and of finite presentations of groups, is based on the so-called word-based distribution: subgroups are generated (finite presentations are determined) by randomly chosen k-tuples of reduced words, whose maximal length is allowed to tend to infinity. In th
Paolo Bellingeri, Sylvain Gervais
In this paper we introduce the framed pure braid group on $n$ strands of an oriented surface, a topological generalisation of the pure braid group $P_n$. We give different equivalents definitions for framed pure braid groups and we study exact sequences relating these groups with other generalisations of $P_n$, usually called surface pure braid groups. The n
Vivien Ripoll
Let A be a polynomial algebra with complex coefficients. Let B be a finite extension ring of A which is also a polynomial algebra. We describe the factorisation of the Jacobian J of the extension into irreducibles. We also introduce the notion of a well-ramified extension and define its discriminant polynomial D. In the particular case where A is the ring of
Timothy Clifton, John D. Barrow
We consider the observational effects of a deficit angle, w, in the topology of the solar system and in the 'double pulsar' system PSR J0737-3039A/B. Using observations of the perihelion precession of Mercury, and the gravitational deflection of light due to the Sun, we constrain the magnitude of such a deficit angle in the solar system to be 2*pi*(1
Cordian Riener
In this note we aim to give a new, elementary proof of a statement that was first proved by Timofte. It says that a symmetric real polynomial $F$ of degree $d$ in $n$ variables is positive on $\R^n$ (on $\R^{n}_{\geq 0}$) if and only if it is so on the subset of points with at most $\max\{\lfloor d/2\rfloor,2\}$ distinct components. We deduce Timofte's o
Modeling Collapse and Accretion in Turbulent Gas Clouds: Implementation and Comparison of Sink Particles in AMR and SPH
astro-ph.SRChristoph Federrath, Robi Banerjee, Paul C. Clark, Ralf S. Klessen
We implemented sink particles in the adaptive mesh refinement (AMR) hydrodynamics code FLASH. Sink particles are created in regions of local gravitational collapse, and their trajectories and accretion can be followed over many dynamical times. We perform a series of tests including the time integration of circular and elliptical orbits, the collapse of a Bo
Kh. Saaidi, A. Vajdi, S. W. Rabiei, A. Aghamohammadi
We introduce a new approach for investigating the weak field limit of vacuum field equations in $f(R)$ gravity and we find the weak field limit of $f(R)=R+μ^4/R$ gravity. Furthermore, we study the strong gravity regime in $R+μ^{4}/R$ model of $f(R)$ gravity. We show the existence of strong gravitational field in vacuum for such model. We find out in the limi
Mikhail Andreev, Ilya Razenshteyn, Alexander Shen
C.Calude, A.Nies, L.Staiger, and F.Stephan posed the following question about the relation between plain and prefix Kolmogorov complexities (see their paper in DLT 2008 conference proceedings): does the domain of every optimal decompressor contain the domain of some optimal prefix-free decompressor? In this paper we provide a negative answer to this question
A. J. Foulkes, V. N. Biktashev
We describe an approach to numerical simulation of spiral waves dynamics of large spatial extent, using small computational grids.
Tim van Erven, Peter Harremoës
Rényi divergence is related to Rényi entropy much like information divergence (also called Kullback-Leibler divergence or relative entropy) is related to Shannon's entropy, and comes up in many settings. It was introduced by Rényi as a measure of information that satisfies almost the same axioms as information divergence. We review the most important pro
Novel Multifunctional Materials Based on Oxide Thin Films and Artificial Heteroepitaxial Multilayers
cond-mat.mtrl-sciMatthias Opel, Stephan Gepraegs, Edwin P. Menzel, Andrea Nielsen
Transition metal oxides show fascinating physical properties such as high temperature superconductivity, ferro- and antiferromagnetism, ferroelectricity or even multiferroicity. The enormous progress in oxide thin film technology allows us to integrate these materials with semiconducting, normal conducting, dielectric or non-linear optical oxides in complex
Mordehai Milgrom
Bimetric MOND (BIMOND) theories, propounded recently, predict peculiar gravitational interactions between matter and twin matter (TM). Twin matter is hypothetical matter that might couple directly only to the second metric of the theory. Considerations of cosmology in the BIMOND framework suggest that such TM might exist and copy matter in its attributes. He
Erik M. Gauger, Joachim Wabnig
We present a theoretical study showing that an optically driven excitonic two-level system in a solid state environment acts as a heat pump by means of repeated phonon emission or absorption events. We derive a master equation for the combined phonon bath and two-level system dynamics and analyze the direction and rate of energy transfer as a function of the
David Cruz-Uribe, Jose Maria Martell, Carlos Perez
We give a new proof of the sharp one weight $L^p$ inequality for any operator $T$ that can be approximated by Haar shift operators such as the Hilbert transform, any Riesz transform, the Beurling-Ahlfors operator. Our proof avoids the Bellman function technique and two weight norm inequalities. We use instead a recent result due to A. Lerner to estimate the
Peter Harremoës, Igor Vajda
We provide a general method for evaluation of the joint range of f-divergences for two different functions f. Via topological arguments we prove that the joint range for general distributions equals the convex hull of the joint range achieved by the distributions on a two-element set. The joint range technique provides important inequalities between differen
R. Bertoni, A. Blondel, M. Bonesini, G. Cecchet
In the MICE experiment at RAL the upstream time-of-flight detectors are used for particle identification in the incoming muon beam, for the experiment trigger and for a precise timing (sigma_t ~ 50 ps) with respect to the accelerating RF cavities working at 201 MHz. The construction of the upstream section of the MICE time-of-flight system and the tests done
MinJi Kim, Muriel Medard
The deterministic wireless relay network model, introduced by Avestimehr et al., has been proposed for approximating Gaussian relay networks. This model, known as the ADT network model, takes into account the broadcast nature of wireless medium and interference. Avestimehr et al. showed that the Min-cut Max-flow theorem holds in the ADT network. In this pape
Raphael Clifford, Markus Jalsenius, Ashley Montanaro, Benjamin Sach
We study the complexity of the popular one player combinatorial game known as Flood-It. In this game the player is given an n by n board of tiles where each tile is allocated one of c colours. The goal is to make the colours of all tiles equal via the shortest possible sequence of flooding operations. In the standard version, a flooding operation consists of
G. Ortenzi, V. Rubtsov, S. R. Tagne Pelap
We study different algebraic and geometric properties of Heisenberg invariant Poisson polynomial quadratic algebras. We show that these algebras are unimodular. The elliptic Sklyanin-Odesskii-Feigin Poisson algebras $q_{n,k}(\mathcal E)$ are the main important example. We classify all quadratic $H-$invariant Poisson tensors on ${\mathbb C}^n$ with $n\leq 6$
V. M. Red'kov, E. M. Ovsiyuk
Exact wave solutions for particles with spin 0, 1/2 and 1 in the static coordinates of the de Sitter space-time model are examined in detail. Firstly, for a scalar particle, two pairs of linearly independent solutions are specified explicitly: running and standing waves. A known algorithm for calculation of the reflection coefficient $R_{εj}$ on the backgrou
Oleg Andreev
We make an estimate of the quadratic correction in the pressure of cold quark matter using gauge/string duality.
G. Bellettini, J. Hoppe, M. Novaga, G. Orlandi
We study various properties of closed relativistic strings. In particular, we characterize their closure under uniform convergence, extending a previous result by Y. Brenier on graph-like unbounded strings, and we discuss some related examples. Then we study the collapsing profile of convex planar strings which start with zero initial velocity, and we obtain
Hasan Sahin, Can Ataca, Salim Ciraci
In this study, we investigate the electronic and magnetic properties of graphane nanoribbons. We find that zigzag and armchair graphane nanoribbons with H-passivated edges are nonmagnetic semiconductors. While bare armchair ribbons are also nonmagnetic, adjacent dangling bonds of bare zigzag ribbons have antiferromagnetic ordering at the same edge. Band gaps
The level crossing and inverse statistic analysis of German stock market index (DAX) and daily oil price time series
q-fin.STF. Shayeganfar, M. Holling, J. Peinke, M. Reza Rahimi Tabar
The level crossing and inverse statistics analysis of DAX and oil price time series are given. We determine the average frequency of positive-slope crossings, $ν_α^+$, where $T_α =1/ν_α^+ $ is the average waiting time for observing the level $α$ again. We estimate the probability $P(K, α)$, which provides us the probability of observing $K$ times of the leve
Jorge Vitoria
Following Artin and Zhang's formulation of noncommutative projective geometry, we classify up a family of skew polynomial quadratic algebras up to graded Morita equivalence and their corresponding noncommutative projective spaces up to birational equivalences. We also study their point varieties and provide examples of non-isomorphic noncommutative proje
Chao-Zhong Wu, Dingdian Xu
We employ a Lax pair representation of the two-component BKP hierarchy and construct its bihamiltonian structure with R-matrix techniques.
Avishy Carmi, Pini Gurfil
We present a computationally-efficient method for recovering sparse signals from a series of noisy observations, known as the problem of compressed sensing (CS). CS theory requires solving a convex constrained minimization problem. We propose to transform this optimization problem into a convex feasibility problem (CFP), and solve it using subgradient projec
Elchanan Zwecher, Dana Porrat
Training over sparse multipath channels is explored. The energy allocation and the optimal shape of training signals that enable error free communications over unknown channels are characterized as a function of the channels' statistics. The performance of training is evaluated by the reduction of the mean square error of the channel estimate and by the
Complex and Hypercomplex Discrete Fourier Transforms Based on Matrix Exponential Form of Euler's Formula
math.RAStephen J. Sangwine, Todd A. Ell
We show that the discrete complex, and numerous hypercomplex, Fourier transforms defined and used so far by a number of researchers can be unified into a single framework based on a matrix exponential version of Euler's formula $e^{jθ}=\cosθ+j\sinθ$, and a matrix root of -1 isomorphic to the imaginary root $j$. The transforms thus defined can be computed
Stability of thin-shell wormholes supported by ordinary matter in Einstein-Maxwell-Gauss-Bonnet gravity
gr-qcS. Habib Mazharimousavi, M. Halilsoy, Z. Amirabi
Recently in (Phys. Rev. D 76, 087502 (2007) and Phys. Rev. D 77, 089903(E) (2008)) a thin-shell wormhole has been introduced in 5-dimensional Einstein-Maxwell-Gauss-Bonnet (EMGB) gravity which was supported by normal matter. We wish to consider this solution and investigate its stability. Our analysis shows that for the Gauss-Bonnet (GB) parameter $α<0,$ sta
Dongsu Bak, Sangheon Yun
To study thermal aspects of the ABJM theory in the strongly coupled regime, we carry out the CP3 invariant dimensional reduction of the type IIA supergravity down to four dimensions. We then investigate zero and finite temperature responses of the operators which are dual to the AdS scalar and vector fields. Two scalar operators are shown to have finite-temp
Gunnar Fløystad, Henning Lohne
We investigate the analogy between squarefree Cohen-Macaulay modules supported on a graph and line bundles on a curve. We prove a Riemann-Roch theorem, we study the Jacobian and gonality of a graph, and we prove Clifford's theorem.
Three-body problem in heteronuclear mixtures with resonant interspecies interaction
cond-mat.quant-gasK. Helfrich, H. -W. Hammer, D. S. Petrov
We use the zero-range approximation to study a system of two identical bosons interacting resonantly with a third particle. The method is derived from effective field theory. It reduces the three-body problem to an integral equation which we then solve numerically. We also develop an alternative approach which gives analytic solutions of the integral equatio
Ming Ding, Fan Xu
Y. Palu has generalized the cluster multiplication formulas to 2-Calabi-Yau categories with cluster tilting objects (\cite{Palu2}). The aim of this note is to construct a variant of Y. Palu's formula and deduce a new version of the cluster multiplication formula (\cite{XiaoXu}) for acyclic quivers in the context of cluster categories.
Koujin Takeda, Yoshiyuki Kabashima
We investigate a reconstruction limit of compressed sensing for a reconstruction scheme based on the L1-norm minimization utilizing a correlated compression matrix with a statistical mechanics method. We focus on the compression matrix modeled as the Kronecker-type random matrix studied in research on multi-input multi-output wireless communication systems.
Bartosz Fornal, Michael Trott
We discuss the potential of measurements of σ(p p -> b\bar{b}) to constrain new bosonic degrees of freedom at the LHC when pT > \sqrt{s}/11 TeV for a pseudorapidity cut |η| < 2.4. By suppressing the NLO QCD production of b\bar{b} pairs through simple kinematic constraints we show how to more efficiently exploit CMS's reach out to 1.5 TeV in pT for B meso
Comparing the Predictions of two Mixed Neutralino Dark Matter Models with the Recent CDMS II Candidate Events
hep-phD. P. Roy
We consider two optimally mixed neutralino dark matter models, based on nonuniversal gaugino masses, which were recently proposed by us to achieve WMAP compatible relic density over a large part of the MSSM parameter space. We compare the resulting predictions for the spin-independent DM scattering cross-section with the recent CDMS II data, assuming the pos
Fan Xu, Xueqing Chen
We define the Hall algebra associated to any triangulated category under some finiteness conditions with the $t$-periodic translation functor $T$ for odd $t>1.$ This generalizes the results in \cite{Toen2005} and \cite{XX2006}.
A. Jesche, C. Krellner, M. de Souza, M. Lang
Using an adapted Sn-flux growth technique we obtained comparatively large CeFeAsO single crystals of better quality than previously reported polycrystals or single crystals, as evidenced by much sharper anomalies at the structural and magnetic phase transitions as well as a much higher residual resistivity ratio of 12. In the magnetically ordered phase we ob
Xiaoji Zhou, Fan Yang, Xuguang Yue, T. Vogt
Superradiance scattering from a Bose-Einstein condensate is studied with a two-frequency pumping beam. We demonstrate the possibility of fully tuning the backward mode population as a function of the locked initial relative phase between the two frequency components of the pumping beam. This result comes from an imprinting of this initial relative phase on t
Rosalie C. McGurk, Amy E. Kimball, Zeljko Ivezic
We apply Principal Component Analysis (PCA) to ~100,000 stellar spectra obtained by the Sloan Digital Sky Survey (SDSS). In order to avoid strong non-linear variation of spectra with effective temperature, the sample is binned into 0.02 mag wide intervals of the g-r color (-0.20<g-r<0.90, roughly corresponding to MK spectral types A3 to K3), and PCA is appli
On the Design of an Optimal Multiprocessor Real-Time Scheduling Algorithm under Practical Considerations (Extended Version)
cs.OSShelby Funk, Vincent Nelis, Joel Goossens, Dragomir Milojevic
This research addresses the multiprocessor scheduling problem of hard real-time systems, and it especially focuses on optimal and global schedulers when practical constraints are taken into account. First, we propose an improvement of the optimal algorithm BF. We formally prove that our adaptation is (i) optimal, i.e., it always generates a feasible schedule
Peyman Niroomand
Let $G$ be a finite $p$-group of order $p^n$. It is known that $|\mathcal{M}(G)|=p^{\f{1}{2}n(n-1)-t(G)}$ and $t(G)\geq 0$. The structure of $G$ characterized when $t(G)\leq 4$ in \cite{be,el,ni,sa,zh}. The structure description of $G$ is determined in this paper for $t(G)=5$.
Jean-Francois Sygnet, Hong Tu, Bernard Fort, Raphael Gavazzi
[ABRIDGED] The new generation of wide field optical imaging like the Canada France Hawaii Telescope Legacy Survey (CFHTLS) enables discoveries of all types of gravitational lenses present in the sky. The Strong Lensing Legacy Survey (SL2S) project has started an inventory, respectively for clusters or groups of galaxies lenses, and for Einstein rings around
Michio Hashimoto
We reanalyze constraints on the mass spectrum of the chiral fourth generation fermions and the Higgs bosons for the standard model (SM4) and the two Higgs doublet model (THDM). We find that the Higgs mass in the SM4 should be larger than roughly the fourth generation up-type quark mass, while the light CP even Higgs mass in the THDM can be smaller. Various m
Approximate bound state solutions of Dirac equation with Hulthén potential including Coulomb-like tensor potential
math-phSameer M. Ikhdair, Ramazan Sever
We solve the Dirac equation approximately for the attractive scalar $S(r)$ and repulsive vector $V(r)$ Hulthén potentials including a Coulomb-like tensor potential with arbitrary spin-orbit coupling quantum number $κ.$ In the framework of the spin and pseudospin symmetric concept, we obtain the analytic energy spectrum and the corresponding two-component upp
Hsien-Hao Mei, Wei-Tou Ni, Sheng-Jui Chen, Sheau-shi Pan
Dark matter is a focused issue in galactic evolution and cosmology. Axion is a viable particle candidate for dark matter. Its interaction with photon is an effective way to detect it, e.g., pseudoscalar-photon interaction will generate vacuum dichroism in a magnetic field. Motivated to measure the QED vacuum birefringence and to detect pseudoscalar-photon in
Minoru Eto
We consider an Abelian BF-Higgs theory with Nf=2 Higgs fields in 1+1 dimensions. We derive a new BPS-like bound and find topological solitons with tri-charges (topological charge, Q-charge and electric charge). We call them "trions."
Denis Auroux
The main goal of this paper is to discuss a symplectic interpretation of Lipshitz, Ozsvath and Thurston's bordered Heegaard-Floer homology in terms of Fukaya categories of symmetric products and Lagrangian correspondences. More specifically, we give a description of the algebra A(F) which appears in the work of Lipshitz, Ozsvath and Thurston in terms of
Yoshiyuki Furuhashi, Masao Hirokawa, Kazumitsu Nakahara, Yutaka Shikano
One-dimensional quantum systems can be experimentally studied in recent nano-technology like the carbon nanotube and the nanowire. We have considered the mathematical model of the one-dimensional Schrödinger particle with a junction and have analyzed the phase factor in the boundary condition of the junction. We have shown that the phase factor in the tunnel
Effect of a Zn impurity on T_c and its implication to pairing symmetry in LaFeAsO$_{1-x}$F$_x$
cond-mat.supr-conYuke Li, Jun Tong, Qian Tao, Chunmu Feng
The effect of non-magnetic Zn impurity on superconductivity in LaFe$_{1-y}$Zn$_y$AsO$_{1-x}$F$_x$ system is studied systematically. In the presence of Zn impurity, the superconducting transition temperature increases in the under-doped regime, remains unchanged in the optimally doped regime, and is severely suppressed in the over-doped regime. Our results su
Mohammad Mehrafarin
We present a gauge-field extension of the Bose condensate model that describes $T\approx0$ superfluid turbulence generated by the macroscopic motion of the superfluid. We first establish that the condensate model is dual to the short-range interacting loop gas model, wherein the loops represent quantum vortex lines. Vortex lines form, interact and proliferat
Ulrich D. Jentschura, Jean Zinn-Justin
The energy levels of quantum systems are determined by quantization conditions. For one-dimensional anharmonic oscillators, one can transform the Schrodinger equation into a Riccati form, i.e., in terms of the logarithmic derivative of the wave function. A perturbative expansion of the logarithmic derivative of the wave function can easily be obtained. The B
On characters and formal degrees of discrete series of affine Hecke algebras of classical types
math.RTDan Ciubotaru, Midori Kato, Syu Kato
We address two fundamental questions in the representation theory of affine Hecke algebras of classical types. One is an inductive algorithm to compute characters of tempered modules, and the other is the determination of the constants in the formal degrees of discrete series (in the form conjectured by Reeder \cite{Re}). The former is completely different t
Real-time digital holographic microscopy observable in multi-view and multi-resolution
physics.opticsTomoyoshi Shimobaba, Nobuyuki Masuda, Yasuyuki Ichihashi, Tomoyoshi Ito
We propose a real-time digital holographic microscopy, that enables simultaneous multiple reconstructed images with arbitrary resolution, depth and positions, using Shifted-Fresnel diffraction instead of Fresnel diffraction. In this system, we used four graphics processing units (GPU) for multiple reconstructions in real-time. We show the demonstration of fo
Mark S. Rudner, Emmanuel I. Rashba
We consider relaxation of an electron spin in a nanotube quantum dot due to its coupling to flexural phonon modes, and identify a new spin-orbit mediated coupling between the nanotube deflection and the electron spin. This mechanism dominates other spin relaxation mechanisms in the limit of small energy transfers. Due to the quadratic dispersion law of long
Jonathan J. Heckman, Jing Shao, Cumrun Vafa
F-theory GUT models favor a relatively narrow range of soft supersymmetry breaking parameters in the MSSM Lagrangian. This leads to the specific predictions that a 10-100 MeV mass gravitino is the LSP, and the NLSP is quasi-stable, with a lifetime between a second to an hour. In a wide range of parameter space, the NLSP turns out to be a stau, though a bino-
Shu-Yu Hsu
Let $g=(g_{ij})$ be a complete Riemmanian metric on $\R^2$ with finite total area and $I_g=\inf_γI(γ)$ with $I(γ)=L(γ)(A_{in}(γ)^{-1}+A_{out}(γ)^{-1})$ where $γ$ is any closed simple curve in $\R^2$, $L(γ)$ is the length of $γ$, $A_{in}(γ)$ and $A_{out}(γ)$ are the area of the regions inside and outside $γ$ respectively, with respect to the metric $g$. We pr
Yoshiyuki Kabashima, Tadashi Wadayama, Toshiyuki Tanaka
We use the replica method of statistical mechanics to examine a typical performance of correctly reconstructing $N$-dimensional sparse vector $bx=(x_i)$ from its linear transformation $by=bF bx$ of $P$ dimensions on the basis of minimization of the $L_p$-norm $||bx||_p= lim_{epsilon to +0} sum_{i=1}^N |x_i|^{p+epsilon}$. We characterize the reconstruction pe
Andrew D. Straw, Kristin Branson, Titus R. Neumann, Michael H. Dickinson
Automated tracking of animal movement allows analyses that would not otherwise be possible by providing great quantities of data. The additional capability of tracking in realtime - with minimal latency - opens up the experimental possibility of manipulating sensory feedback, thus allowing detailed explorations of the neural basis for control of behavior. He
Primordial non-Gaussianity and Bispectrum Measurements in the Cosmic Microwave Background and Large-Scale Structure
astro-ph.COM. Liguori, E. Sefusatti, J. R. Fergusson, E. P. S. Shellard
The most direct probe of non-Gaussian initial conditions has come from bispectrum measurements of temperature fluctuations in the Cosmic Microwave Background and of the matter and galaxy distribution at large scales. Such bispectrum estimators are expected to continue to provide the best constraints on the non-Gaussian parameters in future observations. We r
Moira Chas, Anthony Phillips
We address the problem of computing bounds for the self-intersection number (the minimum number of self-intersection points) of members of a free homotopy class of curves in the doubly-punctured plane as a function of their combinatorial length L; this is the number of letters required for a minimal description of the class in terms of the standard generator
Dorin Ervin Dutkay, Palle E. T. Jorgensen
We consider a family of measures $μ$ supported in $\br^d$ and generated in the sense of Hutchinson by a finite family of affine transformations. It is known that interesting sub-families of these measures allow for an orthogonal basis in $L^2(μ)$ consisting of complex exponentials, i.e., a Fourier basis corresponding to a discrete subset $Γ$ in $\br^d$. Here
Relaxation in homogeneous and non-homogeneous polarized systems. A mesoscopic entropy approach
cond-mat.softJ. G. Méndez-Bermúdez, I. Santamaría-Holek
The dynamics of a degree of freedom associated to an axial vector in contact with a heat bath is decribed by means of a probability distribution function obeying a Fokker-Planck equation. The equation is derived by using mesoscopic non-equilibrium thermodynamics and permits a formulation of a dynamical theory for the axial degree of freedom (orientation, pol
Planck pre-launch status: Low Frequency Instrument calibration and expected scientific performance
astro-ph.IMA. Mennella, M. Bersanelli, R. C. Butler, F. Cuttaia
We give the calibration and scientific performance parameters of the Planck Low Frequency Instrument (LFI) measured during the ground cryogenic test campaign. These parameters characterise the instrument response and constitute our best pre-launch knowledge of the LFI scientific performance. The LFI shows excellent $1/f$ stability and rejection of instrument
High-pressure synthesis, crystal and electronic structures of a new scandium tungstate, Sc0.67WO4
cond-mat.mtrl-sciTamas Varga, J. F. Mitchell, Jun Wang, Lindsay G. Arnold
Negative thermal expansion (NTE) materials possess a low-density, open structure which can respond to high pressure conditions, leading to new compounds and/or different physical properties. Here we report that one such NTE material -- white, insulating, orthorhombic Sc2W3O12 -- transforms into a black compound when treated at 4 GPa and 1400 oC. The high pre
Where do Wet, Dry, and Mixed Galaxy Mergers Occur? A Study of the Environments of Close Galaxy Pairs in the DEEP2 Galaxy Redshift Survey
astro-ph.COLihwai Lin, Michael C. Cooper, Hung-Yu Jian, David C. Koo
We study the environment of wet, dry, and mixed galaxy mergers at 0.75 < z < 1.2 using close pairs in the DEEP2 Galaxy Redshift Survey. We find that the typical environment of mixed and dry merger candidates is denser than that of wet mergers, mostly due to the color-density relation. While the galaxy companion rate (Nc) is observed to increase with overdens
G. -D. Lin, L. -M. Duan
We study thermalization and non-equilibrium dynamics in a dissipative quantum many-body system -- a chain of ions with two points of the chain driven by thermal bath under different temperature. Instead of a simple linear temperature gradient as one expects from the classical heat diffusion process, the temperature distribution in the ion chain shows surpris
Evidence for effective thermal boundary resistance from magnon/phonon disequilibrium
cond-mat.mtrl-sciM. C. Langner, C. L. S. Kantner, Y. H. Chu, L. M. Martin
We use the time-resolved magneto-optical Kerr effect (TRMOKE) to measure the local temperature and heat flow dynamics in ferromagnetic SrRuO3 thin films. After heating by a pump pulse, the film temperature decays exponentially, indicating that the heat flow out of the film is limited by the film/substrate interface. We show that this behavior is consistent w
László Pyber, Endre Szabó
We prove that if L is a finite simple group of Lie type and A a symmetric set of generators of L, then A grows i.e |AAA| > |A|^(1+epsilon) where epsilon depends only on the Lie rank of L, or AAA=L. This implies that for a family of simple groups L of Lie type the diameter of any Cayley graph is polylogarithmic in |L|. Combining our result on growth with know
B. Ricceri
We prove a fixed point theorem for a particular multifunction from the unit sphere of a reflexive Banach space with the Kadec-Klee property into itself.
M. J. Martinez Gonzalez, R. Manso Sainz, A. Asensio Ramos, A. Lopez Ariste
The behavior of the observed polarization amplitudes with spatial resolution is a strong constraint on the nature and organization of solar magnetic fields below the resolution limit. We study the polarization of the very quiet Sun at different spatial resolutions using ground- and space-based observations. It is shown that 80% of the observed polarization s
A. V. Boriskin, R. Sauleau, A. I. Nosich
The role of edge illumination in the performance of compact-size dielectric lens antennas (DLAs) is studied in accurate manner using a highly efficient algorithm based on the combination of the Muller boundary integral equations and the method of analytical regularization. The analysis accounts for the finite size of the lens and directive nature of the prim
Stephane Berciaud, Christophe Voisin, Hugen Yan, Bhupesh Chandra
We examine the excitonic nature of high-lying optical transitions in single-walled carbon nanotubes by means of Rayleigh scattering spectroscopy. A careful analysis of the principal transitions of individual semiconducting and metallic nanotubes reveals that in both cases the lineshape is consistent with an excitonic model, but not one of free-carriers. For
Carlo Contaldi, Fay Dowker, Lydia Philpott
A model of Lorentz invariant random fluctuations in photon polarization is presented. The effects are frequency dependent and affect the polarization of photons as they propagate through space. We test for this effect by confronting the model with the latest measurements of polarization of Cosmic Microwave Background (CMB) photons.
S. Hekker, J. De Ridder, F. Baudin, C. Barban
Observations of red (G-K)-giant stars with the CoRoT satellite provide unprecedented information on the stochastically excited oscillations in these stars. The long time series of nearly uninterrupted high-cadence and high-precision photometry revealed the presence of non-radial modes with long lifetimes, which opens the possibility to perform asteroseismolo
Jean Bourgain, Alex Kontorovich, Peter Sarnak
We prove various orbital counting statements for Fuchsian groups of the second kind. These are of independent interest, and also are used in the companion paper [BourgainKontorovich2009] to produce primes in the Affine Linear Sieve.
The Contribution of Fermi Gamma-Ray Pulsars to the local Flux of Cosmic-Ray Electrons and Positrons
astro-ph.HELeo Gendelev, Stefano Profumo, Michael Dormody
We analyze the contribution of gamma-ray pulsars from the first Fermi-Large Area Telescope (LAT) catalogue to the local flux of cosmic-ray electrons and positrons (e+e-). We present new distance estimates for all Fermi gamma-ray pulsars, based on the measured gamma-ray flux and pulse shape. We then estimate the contribution of gamma-ray pulsars to the local
Jean Bourgain, Alex Kontorovich
Let Gamma < SL(2,Z) be a free, finitely generated Fuchsian group of the second kind with no parabolics, and fix two primitive non-zero vectors v0, w0 in Z^2. We consider the set S of all integers occurring in <v0 gamma,w0>, for gamma in Gamma. Assume that the limit set of Gamma has Hausdorff dimension delta>0.99995, that is, Gamma is thin but not too thin. U
Jeremy Figgins, Dirk K. Morr
We present a large-N theory for the differential conductance, dI/dV, in Kondo systems measured via scanning tunneling spectroscopy. We demonstrate that quantum interference between tunneling processes into the conduction band and into the magnetic f-electron states is crucial in determining the experimental Fano lineshape of dI/dV. This allows one to uniquel
Oscar J. C. Dias, Pau Figueras, Ricardo Monteiro, Harvey S. Reall
We present the first example of a linearized gravitational instability of an asymptotically flat vacuum black hole. We study perturbations of a Myers-Perry black hole with equal angular momenta in an odd number of dimensions. We find no evidence of any instability in five or seven dimensions, but in nine dimensions, for sufficiently rapid rotation, we find p
Henry Eyring: Statistical Mechanics, Significant Structure Theory, and the Inductive-Deductive Method
physics.hist-phDouglas Henderson
Henry Eyring was, and still is, a towering figure in science. Some aspects of his life and science, beginning in Mexico and continuing in Arizona, California, Wisconsin, Germany, Princeton, and finally Utah, are reviewed here. Eyring moved gradually from quantum theory toward statistical mechanics and the theory of liquids, motivated in part by his desire to
Topological Properties of Tensor Network States From Their Local Gauge and Local Symmetry Structures
cond-mat.str-elBrian Swingle, Xiao-Gang Wen
Tensor network states are capable of describing many-body systems with complex quantum entanglement, including systems with non-trivial topological order. In this paper, we study methods to calculate the topological properties of a tensor network state from the tensors that form the state. Motivated by the concepts of gauge group and projective symmetry grou
Loet Leydesdorff, Martin Meyer
University patenting has been heralded as a symbol of changing relations between universities and their social environments. The Bayh-Dole Act of 1980 in the USA was eagerly promoted by the OECD as a recipe for the commercialization of university research, and the law was imitated by a number of national governments. However, since the 2000s university paten
R. E. Felix-Medina, M. A. Leyva-Lucero, R. A. Guirado-Lopez, S. Meza-Aguilar
We present extensive first principles density functional theory (DFT) calculations dedicated to analyze the magnetic and electronic properties of small V$_{n}$ clusters (n=1,2,3,4,5,6) embedded in a Cu fcc matrix. We consider different cluster structures such as: i) a single V impurity, ii) several V$_{2}$ dimers having different interatomic distance and var
Melanie A. Gendre, P. N. Best, J. V. Wall
This paper focuses on a comparison of the space densities of FRI and FRII sources at different epochs, with a particular focus on FRI sources. First, we present the concluding steps in constructing the Combined NVSS-FIRST Galaxy catalogue (CoNFIG), including new VLA observations, optical identifications and redshift estimates. The final catalogue consists of
William J. Henney, Grazyna Stasinska
In planetary nebulae, abundances of oxygen and other heavy elements derived from optical recombination lines are systematically higher than those derived from collisionally excited lines. We investigate the hypothesis that the destruction of solid bodies may produce pockets of cool, high-metallicity gas that could explain these abundance discrepancies. Under
The Importance of XUV Radiation as a Solution to the P V Mass Loss Rate Discrepancy in O-Stars
astro-ph.SRWayne L. Waldron, Joseph P. Cassinelli
A controversy has developed regarding the stellar wind mass loss rates in O-stars. The current consensus is that these winds may be clumped which implies that all previously derived mass loss rates using density-squared diagnostics are overestimated by a factor of ~ 2. However, arguments based on FUSE observations of the P V resonance line doublet suggest th
Walter Bergweiler
Let F be a family of holomorphic functions and let K be a constant less than 4. Suppose that for all f in F the second iterate of f does not have fixed points for which the modulus of the multiplier is greater than K. We show that then F is normal. This is deduced from a result about the multipliers of iterated polynomials.
Vern I. Paulsen
We prove that if a Bessel sequence in a Hilbert space, that is indexed by a countably infinite group in an invariant manner, can be partitioned into finitely many Riesz basic sequences, then each of the sets in the partition can be chosen to be syndetic. We then apply this result to prove that if a Fourier frame for a measurable subset of a higher dimensiona