April 2009 arXiv papers — page 45

Reinhard Schultz

Unpublished results of S Straus and W Browder state that two notions of homotopy equivalence for manifolds with smooth group actions - isovariant and equivariant - often coincide under a condition called the Gap Hypothesis; the proofs use deep results in geometric topology. This paper analyzes the difference between the two types of maps from a homotopy theo

Jiang Wei, Zenghui Wang, Wei Chen, David H. Cobden

Many strongly correlated electronic materials, including high-temperature superconductors, colossal magnetoresistance and metal-insulator-transition (MIT) materials, are inhomogeneous on a microscopic scale as a result of domain structure or compositional variations. An important potential advantage of nanoscale samples is that they exhibit the homogeneous p

I. Shipsey, L. Buckley-Geer, P. Burchat, D. Burke

We discuss some of the key science questions that are bringing particle physicists and astrophysicists together, and comment on some of the cultural and funding issues that have arisen as these two communities become increasingly intertwined.

Eriko Hironaka, Eiko Kin

This paper describes a family of pseudo-Anosov braids with small dilatation. The smallest dilatations occurring for braids with 3, 4 and 5 strands appear in this family. A pseudo-Anosov braid with 2g+1 strands determines a hyperelliptic mapping class with the same dilatation on a genus-g surface. Penner showed that logarithms of least dilatations of pseudo-A

William M. Jackson, XueLiang Yang, Xiaoyu Shi, Anita L. Cochran

The time dependence of the changes in the emission spectra of Comet 9P/Tempel 1 after Deep Impact are derived and discussed. This was a unique event because for the first time it gave astronomers the opportunity to follow the time history of the formation and decay of O(1S), OH, CN, C2, C3, NH, and NH2. Least squares fits of a modified Haser model with const

Stefano Pigola, Giona Veronelli

We prove global comparison results for the $p$-Laplacian on a $p$-parabolic manifold. These involve both real-valued and vector-valued maps with finite $p$-energy.

M. Kachelriess, S. Ostapchenko, R. Tomas

We calculated for the nearest active galactic nucleus (AGN), Centaurus A (Cen A), the flux of high energy cosmic rays and of accompanying secondary photons and neutrinos expected from hadronic interactions in the source. We used as two basic models for the generation of ultrahigh energy cosmic rays (UHECR) shock acceleration in the radio jet and acceleration

Van Hung Le, Fei Liu, Dinh Khang Tran

The paper introduces fuzzy linguistic logic programming, which is a combination of fuzzy logic programming, introduced by P. Vojtas, and hedge algebras in order to facilitate the representation and reasoning on human knowledge expressed in natural languages. In fuzzy linguistic logic programming, truth values are linguistic ones, e.g., VeryTrue, VeryProbably

Ahmed Jellal, Abdulaziz D. Alhaidari, Hocine Bahlouli

We obtain an exact solution of the Dirac equation in (2+1)-dimensions in the presence of a constant magnetic field normal to the plane together with a two-dimensional Dirac-oscillator potential coupling. The solution space consists of a positive and negative energy solution, each of which splits into two disconnected subspaces depending on the sign of an azi

Hassane. Alla

The place invariant method is well known as an elegant way to construct a Petri net controller. It is possible to use the constraint for preventing forbidden states. But in general case, the number forbidden states can be very large giving a great number of control places. In this paper is presented a systematic method to reduce the size and the number of co

Abbas Dideban, M. Zareiee, Hassane Alla

This paper addresses the problem of forbidden states for safe Petri net modeling discrete event systems. We present an efficient method to construct a controller. A set of linear constraints allow forbidding the reachability of specific states. The number of these so-called forbidden states and consequently the number of constraints are large and lead to a l

Ryota Tomioka, Masashi Sugiyama

We propose an efficient algorithm for sparse signal reconstruction problems. The proposed algorithm is an augmented Lagrangian method based on the dual sparse reconstruction problem. It is efficient when the number of unknown variables is much larger than the number of observations because of the dual formulation. Moreover, the primal variable is explicitly

Karthekeyan Chandrasekaran, Daniel Dadush, Santosh Vempala

Star-shaped bodies are an important nonconvex generalization of convex bodies (e.g., linear programming with violations). Here we present an efficient algorithm for sampling a given star-shaped body. The complexity of the algorithm grows polynomially in the dimension and inverse polynomially in the fraction of the volume taken up by the kernel of the star-sh

Pierre Le Doussal, Yoav Etzioni, Baruch Horovitz

We consider a smooth, rotationally invariant, centered gaussian process in the plane, with arbitrary correlation matrix $C_{t t'}$. We study the winding angle $ϕ_t$ around its center. We obtain a closed formula for the variance of the winding angle as a function of the matrix $C_{tt'}$. For most stationary processes $C_{tt'}=C(t-t')$ the wind

C. Lemell, B. Solleder, K. Tokesi, J. Burgdoerfer

First time-resolved photoemission experiments employing attosecond streaking of electrons emitted by an XUV pump pulse and probed by a few-cycle NIR pulse found a time delay of about 100 attoseconds between photoelectrons from the conduction band and those from the 4f core level of tungsten. We present a microscopic simulation of the emission time and energy

N. A. Laoufi, A. Alatrache, Marie-Noëlle Pons, Orfan Zahraa

The photocatalytic degradation of tylosin has been studied using immobilized titanium dioxide as catalyst. T he processes of degradation and reduction of tylosin was examined, and the activity is dominantly dependent on the surface coverage of the catalysts, The Langmuir-Hinshelwood model is satisfactorily obeyed at initial time and in the course of the reac

Marie Faure, Mark Furman, Serge Corbel, Marie-Christiane Carré

Photocatalysis is often used in air purification. Photocatalytic degradation od VOC's has been investigated in a number of devices. An optimisation of this process requires a chracterisation of the reactor : in a first step the gas flow behaviour has to be studied (plug flow, CSTR,...) by RTD analysis; then, chemical kinetics have to be determined as a f

Francesco Cianfrani, Giovanni Montani

A review of the Kaluza-Klein formulation is provided, with a particular emphasis on the geometrization issue. The failure at reproducing quantum numbers of particles and the appearance of huge mass terms are outlined. The possibility to solve these points by an extended approach based on an averaging procedure is discussed.

Francesco Cianfrani, Giovanni Montani

We present the Hamiltonian formulation of General Relativity with the Holst formulation in a generic local Lorentz frame. In particular, we outline that a Gauss constraint is inferred by a proper generalization of Ashtekar-Barbero-Immirzi connections. This feature allow to extend the Loop Quantum Gravity quantization procedure to the case in which no gauge f

J. C. Gonzalez Davila, F. Martin Cabrera

We prove that a 2n-dimensional compact homogeneous nearly Kahler manifold with strictly positive sectional curvature is isometric to CP^{n}, equipped with the symmetric Fubini-Study metric or with the standard Sp(m)-homogeneous metric, n =2m-1, or to S^{6} as Riemannian manifold with constant sectional curvature. This is a positive answer for a revised versi

A. Sollima, M. Bellazzini, R. L. Smart, M. Correnti

We present the results of a survey of radial velocities over a wide region extending from r~10 arcmin out to r~80 arcmin (~1.5 tidal radii) within the massive star cluster omega Centauri. The survey was performed with FLAMES@VLT, to study the velocity dispersion profile in the outer regions of this stellar system. We derived accurate radial velocities for a

Giovanni Montani, Nakia Carlevaro, Francesco Cianfrani, Valentino Lacquaniti

Recent developments from the activity of the CGM Group are discussed. Cosmological implications of fundamental approaches to quantization of gravity are presented in order to fix the main issues as well as perspectives for future investigations. Particular attention will be devoted to the classical and quantum features of the generic inhomogeneous Universe,

Masahiko Ito

We present an explicit expression for the $q$-difference system, which the $BC_1$-type Jackson integral ($q$-series) satisfies, as first order simultaneous $q$-difference equations with a concrete basis. As an application, we give a simple proof for the hypergeometric summation formula introduced by Gustafson and the product formula of the $q$-integral intro

H. Lietzen, P. Heinamaki, P. Nurmi, E. Tago

For the first time spectroscopic galaxy redshift surveys are reaching the scales where galaxies can be studied together with the nearest quasars. This gives an opportunity to study the dependence between the activity of a quasar and its environment in a more extensive way than before. We study the spatial distribution of galaxies and groups of galaxies in th

F. Bresme, H. Lehle, M. Oettel

We investigate the solvent mediated interactions between nanoparticles adsorbed at a liquid-vapor interface in comparison to the solvent mediated interactions in the bulk liquid and vapor phases of a Lennard-Jones solvent. Molecular dynamics simulation data for the latter are in good agreement with results from integral equations in the reference functional

Jun Ma, Zhou Fan, Richard de Grijs, Zhenyu Wu

This paper supplements Jiang et al. (2003), who studied 172 M31 globular clusters (GCs) and globular cluster candidates from Battistini et al. (1987) on the basis of integrated photometric measurements in the Beijing-Arizona-Taiwan-Connecticut (BATC) photometric system. Here, we present multicolor photometric CCD data (in the BATC system) for the remaining 3

Marco Battaglia, Devis Contarato, Peter Denes, Dionisio Doering

This paper presents the results of a study of the response of a test CMOS sensor with a radiation tolerant pixel cell design to 80 keV and 100 keV electrons. The point spread function is measured to be (13.0+/- 1.7) microns at 100 keV and (12.1 +/- 1.6) microns at 80 keV, for 20 micron pixels. Results agree well with values predicted by a Geant-4 and dedicat

Yu. M. Zinoviev

In this paper we consider frame-like formulation for mixed symmetry spin-tensors corresponding to arbitrary Young tableau with two rows. First of all, we extend Skvortsov formulation for massless mixed symmetry bosonic fields in flat Minkowski space to the case of massless fermionic fields. Then, using such massless fields as building blocks, we construct ga

V. De Donno, G. Co', C. Maieron, M. Anguiano

We have studied the low lying magnetic spectra of 12C, 16O, 40Ca, 48Ca and 208Pb nuclei within the Random Phase Approximation (RPA) theory, finding that the description of low-lying magnetic states of doubly-closed-shell nuclei imposes severe constraints on the spin and tensor terms of the nucleon-nucleon effective interaction. We have first made an investig

Z. Qian, C. Xu

In this article we establish a large deviation principle for the family {ν_ε:ε\in (0,1)} of distributions of the scaled stochastic processes {P_{-\log\sqrtε}Z_t}_{t\leq 1}, where (Z_t)_{t\in \lbrack 0,1]} is a square-integrable martingale over Brownian filtration and (P_t)_{t\geq 0} is the Ornstein-Uhlenbeck semigroup. The rate function is identified as well

Petar Kormushev, Kohei Nomoto, Fangyan Dong, Kaoru Hirota

A mechanism called Eligibility Propagation is proposed to speed up the Time Hopping technique used for faster Reinforcement Learning in simulations. Eligibility Propagation provides for Time Hopping similar abilities to what eligibility traces provide for conventional Reinforcement Learning. It propagates values from one state to all of its temporal predeces

Jaeok Park, Mihaela van der Schaar

We study mission-critical networking in wireless communication networks, where network users are subject to critical events such as emergencies and crises. If a critical event occurs to a user, the user needs to send necessary information for help as early as possible. However, most existing medium access control (MAC) protocols are not adequate to meet the

Markus Reiss, Yves Rozenholc, Charles-Andre Cuenod

A nonparametric procedure for robust regression estimation and for quantile regression is proposed which is completely data-driven and adapts locally to the regularity of the regression function. This is achieved by considering in each point M-estimators over different local neighbourhoods and by a local model selection procedure based on sequential testing.

V. P. Efrosinin

The possible source of the production of neutrino with large masses is considered. For this purpose the reaction nu+n to e+p+gamma, in which the electron in neW+ vertex is produced off-mass-shell, is studied.

Eduard Ortega, Francesc Perera, Mikael Rordam

The Corona Factorization Property of a C*-algebra, originally defined to study extensions of C*-algebras, has turned out to say something important about intrinsic structural properties of the C*-algebra. We show in this paper that a σ-unital C*-algebra A of real rank zero has the Corona Factorization roperty if and only if its monoid V(A) of Murray-von Neum

L. Brey, H. A. Fertig

We investigate the effect of a periodic potential on the electronic states and conductance of graphene. It is demonstrated that for a cosine potential $V(x)=V_0\cos(G_0x)$, new zero energy states emerge whenever $J_0(\frac {2V_0}{\hbar v_F G_0})=0$. The phase of the wavefunctions of these states is shown to be related to periodic solutions of the equation of

Allan Gut, Ulrich Stadtmueller

Various methods of summation for divergent series of real numbers have been generalized to analogous results for sums of iid random variables. The natural extension of results corresponding to Cesàro summation amounts to proving almost sure convergence of the Cesàro means. In the present paper we extend such results as well as weak laws and results on comple

John H. Schwarz

Joel Scherk (1946--1980) was an important early contributor to the development of string theory. Together with various collaborators, he made numerous profound and influential contributions to the subject throughout the decade of the 1970s. On the occasion of a conference at the Ecole Normale Superieure in 2000 that was dedicated to the memory of Joel Scherk

Tatiana Latychevskaia, Hans-Werner Fink

We present a reconstruction technique for simultaneous retrieval of absorption and phase shifting properties of an object recorded by in-line holography. The routine is experimentally tested by applying it to optical holograms of a pure phase respectively amplitude object of micrometer dimensions that has been machined into a glass-plate using a focused ion

Alexey V. Bolsinov, Vladimir S. Matveev

Two metrics $g $ and $\bar g$ are geodesically equivalent, if they share the same (unparameterized) geodesics. We introduce two constructions that allow one to reduce many natural problems related to geodesically equivalent metrics, such as the classification of local normal forms and the Lie problem (the description of projective vector fields), to the case

Pabitra Pal Choudhury, Sudhakar Sahoo, Birendra Kumar Nayak, Sk. Sarif Hassan

In this paper the theory of Carry Value Transformation (CVT) is designed and developed on a pair of n-bit strings and is used to produce many interesting patterns. One of them is found to be a self-similar fractal whose dimension is same as the dimension of the Sierpinski triangle. Different construction procedures like L-system, Cellular Automata rule, Till

Paula Benaglia

Some early-type stars are detectable radio emitters; their spectra can present both thermal and non-thermal contributions. Here I review the public radio data on OB stars, focusing on the non-thermal sources. The analysis of the statistical results gives rise to many open questions that are expected to be addressed, at least in part, with the upgrades of cur

A. de Visser, N. T. Huy, A. Gasparini, D. E. de Nijs

We report zero-field muon spin rotation and relaxation measurements on the superconducting ferromagnet UCoGe. Weak itinerant ferromagnetic order is detected by a spontaneous muon spin precession frequency below the Curie temperature $T_C = 3$ K. The $μ^+$ precession frequency persists below the bulk superconducting transition temperature $T_{sc} = 0.5$ K, wh

M. Mapelli, E. Ripamonti, G. Battaglia, E. Tolstoy

The existence of blue straggler stars (BSSs) in dwarf spheroidal galaxies (dSphs) is still an open question. In fact, many BSS candidates have been observed in the Local Group dSphs, but it is unclear whether they are real BSSs or young stars. Shedding light on the nature of these BSS candidates is crucial, in order to understand the star formation history o

Tomasz Konopka

Vacuum energy in quantum field theory, being the sum of zero-point energies of all field modes, is formally infinite but yet, after regularization or renormalization, can give rise to finite observable effects. One way of understanding how these effects arise is to compute the vacuum energy in an idealized system such as a large cavity divided into disjoint

Roberto Capuzzo-Dolcetta, Alessandra Mastrobuono-Battisti

In this paper we analyze data of 8 elliptical galaxies in order to study the difference between their globular cluster systems (GCSs) radial distributions and those of the galactic stellar component. In all the galaxies studied here the globular cluster system density profile is significantly flatter toward the galactic centre than that of stars. If this dif

Zhi-Han Gao, Fang-Wei Fu

Recently, motivated by the study of vectorized stream cipher systems, the joint linear complexity and joint minimal polynomial of multisequences have been investigated. Let S be a linear recurring sequence over finite field F_{q^m} with minimal polynomial h(x) over F_{q^m}. Since F_{q^m} and F_{q}^m are isomorphic vector spaces over the finite field F_q, S i

Marc Ensenbach

Given three lists of ideals of a Dedekind domain, the question is raised, whether there exist two matrices A and B with entries in the given Dedekind domain, such that the given lists of ideals are the determinantal divisors of A, B, and AB, respectively. To answer this question, necessary and sufficient conditions are developed in this article.

S. Pfalzner

Most stars do not form in isolation but as part of a cluster comprising anywhere between a few dozen to several million stars with stellar densities ranging from 0.01 to several 10$^5$ \Msun pc$^{-3}$. The majority of these clusters dissolve within 20 Myr. The general assumption is that clusters are born more or less over this entire density range. A new ana

A. Grönlund, B. Eliasson, M. Marklund

Large amplitude water waves on deep water has long been known in the sea faring community, and the cause of great concern for, e.g., oil platform constructions. The concept of such freak waves is nowadays, thanks to satellite and radar measurements, well established within the scientific community. There are a number of important models and approaches for th

Chang-Hui Li, Fen Wang, Yi Liu, Xiang-Qun Zhang

LuFe2O4 exhibits multiferroicity due to charge order on a frustrated triangular lattice. We find that the magnetization of LuFe2O4 in the multiferroic state can be electrically controlled by applying voltage pulses. Depending on with or without magnetic fields, the magnetization can be electrically switched up or down. We have excluded thermal heating effect

M. Kohno, Y. Fujiwara

Localized single-particle potentials for all octet baryons, $N$, $Λ$, $Σ$, and $Ξ$, in finite nuclei, $^{12}$C, $^{16}$O, $^{28}$Si, $^{40}$Ca, $^{56}$Fe, and $^{90}$Zr, are calculated using the quark-model baryon-baryon interactions. $G$-matrices evaluated in symmetric nuclear matter in the lowest order Brueckner theory are applied to finite nuclei in local

Henryk Czyz, Johann H. Kuhn

A combined analysis of the electromagnetic pion and kaon form factors in the neighborhood of J/psi and psi(2S) and of the strong decay amplitude of these resonances into kaons is presented. In the presence of a large relative phase between strong and electromagnetic resonance amplitudes the branching ratio, as measured in electron-positron annihilation, rece

J. H. Asad, A. J. Sakaji, R. S. Hijjawi, J. M. Khalifeh

A review of the theoretical approach for calculating the resistance between two arbitrary lattice points in an infinite square lattice (perfect and perturbed cases)is carried out using the Lattice Green's Function. We show how to calculate the resistance between the origin and any other site using the Lattice Green's Function at the origin, and its d

Surya K. Ghosh, Kulveer Singh, Anirban Sain

Recently many important biopolymers have been found to possess intrinsic curvature. Tubulin protofilaments in animal cells, FtsZ filaments in bacteria and double stranded DNA are examples. We examine how intrinsic curvature influence the conformational statistics of such polymers. We give exact results for the tangent-tangent spatial correlation function C(r

J. H. Asad

A first order differential equation of Green's Function, at the origin G(0), for the one- dimensional lattice is derived by simple recurrence relation. Green's Function at site (m)is then calculated in terms of G(0). A simple recurrence relation connecting the lattice Green's Function at the site (m,n)and the first derivative of the lattice Green

Qing-hai Wang

Two-dimensional PT-symmetric quantum-mechanical systems with the complex cubic potential V_{12}=x^2+y^2+igxy^2 and the complex Henon-Heiles potential V_{HH}=x^2+y^2+ig(xy^2-x^3/3) are investigated. Using numerical and perturbative methods, energy spectra are obtained to high levels. Although both potentials respect the PT symmetry, the complex energy eigenva

Jing Chen, Ya Cheng, Zhizhan Xu

Wavelength scaling law for the yield of high-order harmonic emission is theoretically examined for excited state atoms which are optically prepared by simultaneously exposing to an extreme ultraviolet pulse at the resonant wavelength and an infrared pulse at a variable wavelength in the range of 0.8\mum-2.4\mum. Numerical simulations are performed based on t

Jiajun Zhang, Zhanjiang Yuan, Tianshou Zhou

The effect of signal integration through cis-regulatory modules (CRMs) on synchronization and clustering of populations of two-component genetic oscillators coupled by quorum sensing is in detail investigated. We find that the CRMs play an important role in achieving synchronization and clustering. For this, we investigate 6 possible cis-regulatory input fun

Wang ZhiZhang

The present paper discusses that a prescribed Gauss-Kronecker curvature problem on the product of unit spheres.

Dengkai Jiang, Zhanwen Han, Tianyu Jiang, Lifang Li

The energy transfer of W UMa contact binaries and its effects on the secondary in W UMa contact binaries are investigated. Relations are given between the mass ratio (q) and the relative energy transfer rates, i.e. U1, the ratio of the transferred luminosity to the surface luminosity of the primary and U2, the ratio of the transferred luminosity to the nucle

Atsushi Nakayashiki

The space of functions A over the phase space of KdV-hierarchy is studied as a module over the ring D generated by commuting derivations. A D-free resolution of A is constructed by Babelon, Bernard and Smirnov by taking the classical limit of the construction in quantum integrable models assuming a certain conjecture. We propose another D-free resolution of

M. Sultan Parvez, F. Bary Malik

The expression for super-allowed beta-decay transition rates have been derived within the context of Coriolis coupling model. The derived expressions, valid for the beta-decay between any two mirror nuclei, has been applied to calculate super-allowed beta-decay transition rates of 21Na, 21Mg, 21Al, and 21Si. The calculated rates agree well with the data and

Yonina C. Eldar, Holger Rauhut

In this paper, we consider recovery of jointly sparse multichannel signals from incomplete measurements. Several approaches have been developed to recover the unknown sparse vectors from the given observations, including thresholding, simultaneous orthogonal matching pursuit (SOMP), and convex relaxation based on a mixed matrix norm. Typically, worst-case an

Enrique Pazos, Manuel Tiglio, Matthew D. Duez, Lawrence E. Kidder

We present numerical simulations of orbiting black holes for around twelve cycles, using a high-order multipatch approach. Unlike some other approaches, the computational speed scales almost perfectly for thousands of processors. Multipatch methods are an alternative to AMR (adaptive mesh refinement), with benefits of simplicity and better scaling for improv

M. Cristina Caputo, Panagiota Daskalopoulos, Natasa Sesum

We prove the existence and uniqueness of a $C^{1,1}$ solution of the $Q_k$ flow in the viscosity sense for compact convex hypersurfaces $Σ_t$ embedded in $R^{n+1}$ ($n \geq 2$) . In particular, for compact convex hypersurfaces with flat sides we show that, under a certain non-degeneracy initial condition, the interface separating the flat from the strictly c

Marcelo Alves Pereira, Alexandre Souto Martinez

The lowest temptation level (T = 1) is considered a trivial case for the Prisoner's Dilemma. Here, we show that this statement is true only for a very particular case, where the players interact with only one player. Otherwise, if the players interact with more than one player, the system presents the same possible behaviors observed for $T > 1$. In the

Burin Gumjudpai, John Ward

We investigate the phase space of a quintessence theory governed by a generalised version of the DBI action, using a combination of numeric and analytic methods. The additional degrees of freedom lead to a vastly richer phase space structure, where the field covers the full equation of state parameter space; $-1 \le ω\le 1$. We find many non-trivial solution

B. Stokic, B. Friman, K. Redlich

The critical behavior of the chiral quark-meson model is studied within the Functional Renormalization Group (FRG). We derive the flow equation for the scale dependent thermodynamic potential at finite temperature and density in the presence of a symmetry-breaking external field. Within this scheme, the critical scaling behavior of the order parameter, its t

S. Gustafson, K. Nakanishi, T. -P. Tsai

We consider the Landau-Lifshitz equations of ferromagnetism (including the harmonic map heat-flow and Schroedinger flow as special cases) for degree m equivariant maps from R^2 to S^2. If m \geq 3, we prove that near-minimal energy solutions converge to a harmonic map as t goes to infinity (asymptotic stability), extending previous work down to degree m = 3.

Philip Phillips

The arguments presented in PRL. vol. 102, 056404 (2009) are discussed in the context of the vast literature on spectral weight transfer in doped Mott insulators. We show that the conclusions regarding spectral weight transfer in PRL. vol. 102, 056404 (2009) are, where novel, internally inconsistent and where correct, have been reached at least 18 years ago.

Kevin Zumbrun

We perform error analyses explaining some previously mysterious phenomena arising in numerical computation of the Evans function, in particular (i) the advantage of centered coordinates for exterior product and related methods, and (ii) the unexpected stability of the (notoriously unstable) continuous orthogonalization method of Drury in the context of Evans

Andreas Klöckner, Tim Warburton, Jeffrey Bridge, Jan S. Hesthaven

Discontinuous Galerkin (DG) methods for the numerical solution of partial differential equations have enjoyed considerable success because they are both flexible and robust: They allow arbitrary unstructured geometries and easy control of accuracy without compromising simulation stability. Lately, another property of DG has been growing in importance: The ma

Claudia Maria Egea, Esther Galina

We give a method to produce representations of the braid group $B_n$ of $n-1$ generators ($n\leq \infty$). Moreover, we give sufficient conditions over a non unitary representation for being of this type. This method produces examples of irreducible representations of finite and infinite dimension.

Utpal Roy, Suranjana Ghosh, P. K. Panigrahi, David Vitali

We find the existence of sub-Planck scale structures in the P{ö}schl-Teller potential, which is an exactly solvable potential with both symmetric and asymmetric features. We analyze these structures in both cases by looking at the Wigner distribution of the state evolved from an initial coherent state up to various fractional revival times. We also investiga

Yi-Fang Chang

First, we point out that the present applied superposition principle is linear, it must be developed into a generality. Next, the linear operators and equations should be developed nonlinearly. They will include nonlinear Klein-Gordon equation and Dirac equations, and corresponding Heisenberg equation. The quantum commutation and anticommutation should be de

Marcus Tegel, Franziska Hummel, Sebastian Lackner, Inga Schellenberg

Polycrystalline samples of the layered iron arsenides Sr2CrO3FeAs and Ba2ScO3FeAs were synthesized by high temperature solid state reactions and their crystal structures determined by the X-ray powder diffraction. Their structures are tetragonal (P4/nmm; Sr2CrO3FeAs: a = 391.12(1) pm, c = 1579.05(3) pm; Ba2ScO3FeAs: a = 412.66(5) pm, c = 1680.0(2) pm, Z = 2)

Lenka Zdeborová, Aurélien Decelle, Michael Chertkov

We use a power grid model with $M$ generators and $N$ consumption units to optimize the grid and its control. Each consumer demand is drawn from a predefined finite-size-support distribution, thus simulating the instantaneous load fluctuations. Each generator has a maximum power capability. A generator is not overloaded if the sum of the loads of consumers c

Victor Beresnevich

This work is motivated by problems on simultaneous Diophantine approximation on manifolds, namely, establishing Khintchine and Jarnik type theorems for submanifolds of R^n. These problems have attracted a lot of interest since Kleinbock and Margulis proved a related conjecture of Alan Baker and V.G. Sprindzuk. They have been settled for planar curves but rem

Kevin Ford, Sergei V. Konyagin, Florian Luca

We study the distribution of prime chains, which are sequences p_1,...,p_k of primes for which p_{j+1}\equiv 1\pmod{p_j} for each j. We give estimates for the number of chains with p_k\le x (k variable), and the number of chains with p_1=p and p_k \le px. The majority of the paper concerns the distribution of H(p), the length of the longest chain with p_k=p,

Zoltan Muzsnay, Peter T. Nagy

The aim of this paper is to show that holonomy properties of Finsler manifolds can be very different from those of Riemannian manifolds. We prove that the holonomy group of a positive definite non-Riemannian Finsler manifold of non-zero constant curvature with dimension >2 cannot be a compact Lie group. Hence this holonomy group does not occur as the holonom

J F Laprise, A Hosseinizadeh, H Kroger, R Zomorrodi

For classical billiards we suggest that a matrix of action or length of trajectories in conjunction with statistical measures, level spacing distribution and spectral rigidity, can be used to distinguish chaotic from integrable systems. As examples of 2D chaotic billiards we considered the Bunimovich stadium billiard and the Sinai billiard. In the level spac

F. I. Cooperstock, M. J. Dupre

We introduce a naturally-defined totally invariant spacetime energy expression for general relativity incorporating the contribution from gravity. The extension links seamlessly to the action integral for the gravitational field. The demand that the general expression for arbitrary systems reduces to the Tolman integral in the case of stationary bounded dist

David J. Schlegel, Chris Bebek, Henry Heetderks, Shirley Ho

The BigBOSS experiment is a proposed DOE-NSF Stage IV ground-based dark energy experiment to study baryon acoustic oscillations (BAO) and the growth of structure with an all-sky galaxy redshift survey. The project is designed to unlock the mystery of dark energy using existing ground-based facilities operated by NOAO. A new 4000-fiber R=5000 spectrograph cov

Andrew Putman

We give a new proof of a celebrated theorem of Dennis Johnson that asserts that the kernel of the Johnson homomorphism on the Torelli subgroup of the mapping class group is generated by separating twists. In fact, we prove a more general result that also applies to "subsurface Torelli groups". Using this, we extend Johnson's calculation of the rational abeli

Willie Wai-Yeung Wong, Pin Yu

The strong unique continuation property for Einstein metrics can be concluded from the well-known fact that Einstein metrics are analytic in geodesic normal coordinates. Here we give a proof of the same result that given two Einstein metrics with the same Ricci curvature on a fixed manifold, if they agree to infinite order around a point, then they must coin

Daniel Freeman, Edward Odell, Thomas Schlumprecht

Let $X$ be a Banach space with a separable dual. We prove that $X$ embeds isomorphically into a $\cL_\infty$ space $Z$ whose dual is isomorphic to $\ell_1$. If, moreover, $U$ is a space so that $U$ and $X$ are totally incomparable, then we construct such a $Z$, so that $Z$ and $U$ are totally incomparable. If $X$ is separable and reflexive, we show that $Z$

Amit Giveon, David Kutasov, Jock McOrist, Andrew B. Royston

Metastable supersymmetry breaking configurations of D-branes and NS5-branes in string theory often owe their existence to classical gravitational interactions between the branes. We show that in the effective theory of the light fields, these interactions give rise to a non-canonical Kähler potential and other D-terms. String theory provides a UV completion

Kresimir Kumericki, Dieter Mueller

We give a partonic interpretation for the deeply virtual Compton scattering (DVCS) measurements of the H1 and ZEUS collaborations in the small-x_B region in terms of generalized parton distributions. Thereby we have a closer look at the skewness effect, parameterization of the t-dependence, revealing the chromomagnetic pomeron, and at a model dependent acces

R. Demkowicz-Dobrzanski, U. Dorner, B. J. Smith, J. S. Lundeen

We give a detailed discussion of optimal quantum states for optical two-mode interferometry in the presence of photon losses. We derive analytical formulae for the precision of phase estimation obtainable using quantum states of light with a definite photon number and prove that maximization of the precision is a convex optimization problem. The correspondin

M. A. Tschopp, B. B. Bartha, W. J. Porter, P. T. Murray

Digital image correlation of laser-ablated platinum nanoparticles on the surface of a polycrystalline metal (nickel-based superalloy Rene 88DT) was used to obtain the local strain behavior from an in situ scanning electron microscope tensile experiment at room temperature. By fusing this information with crystallographic orientations from EBSD, a subsequent

Edith Adan-Bante, John M. Harris

Let SL(2,q) be the group of 2X2 matrices with determinant one over a finite field F of size q. We prove that if q is even, then the product of any two noncentral conjugacy classes of SL(2,q) is the union of at least q-1 distinct conjugacy classes of SL(2,q). On the other hand, if q>3 is odd, then the product of any two noncentral conjugacy classes of SL(2,q)

Diego Trancanelli

We investigate a strong coupling expansion of N=6 superconformal Chern-Simons theory obtained from the semiclassical analysis of low energy, effective degrees of freedom given by the eigenvalues of a certain matrix model. We show how the orbifolded sphere S^7/Z_k of the dual geometry emerges dynamically from the distribution of the eigenvalues. As a test of

S. Giodini, D. Pierini, A. Finoguenov, G. W. Pratt

We investigate if the discrepancy between estimates of the total baryon mass fraction obtained from observations of the cosmic microwave background (CMB) and of galaxy groups/clusters persists when a large sample of groups is considered. To this purpose, 91 candidate X-ray groups/poor clusters at redshift 0.1 < z < 1 are selected from the COSMOS 2 deg^2 surv

Ming Zhang, Zhi-Gang Xiao, Bao-An Li, Lie-Wen Chen

A systematic study of the $π^-/π^+$ ratio in heavy-ion collisions with the same neutron/proton ratio but different masses can help single out effects of the nuclear mean field on pion production. Based on simulations using the IBUU04 transport model, it is found that the $π^-$ / $π^+$ ratio in head-on collisions of $^{48}$Ca+$^{48}$Ca, $^{124}$Sn +$^{124}$Sn

Bernhard Wunsch

We study the few-electron eigenspectrum of a nanotube quantum dot with spin-orbit coupling. The two-electron phase diagram as a function of the length of the dot and the applied parallel magnetic field shows clear signatures of both spin-orbit coupling and electron-electron interaction. Below a certain critical length, ground state transitions are correctly

David Berenstein, Diego Trancanelli

We use S-duality and planarity to propose an argument for the non-renormalization of the dispersion relation of giant magnon solutions in type IIB string theory on AdS_5 x S^5. We compute the spectrum of giant magnons for (p,q)-strings from field theory at strong coupling by using the central charge properties of electrically and magnetically charged supersy

Claudio Ciofi degli Atti, Chiara Benedetta Mezzetti

In view of recent data from the Thomas Jefferson National Accelerator Facility (JLab) on inclusive electron scattering off nuclei at high momentum transfer (Q^2 > 1 GeV^2) and their current analysis, it is shown that, if the scaling variable is properly chosen, the analysis in terms of scaling functions can provide useful information on Short Range Correlati

Paulo F. Bedaque, Michael I. Buchoff, Aleksey Cherman, Roxanne P. Springer

This paper explores whether Eguchi-Kawai reduction for gauge theories with adjoint fermions is valid. The Eguchi-Kawai reduction relates gauge theories in different numbers of dimensions in the large $N$ limit provided that certain conditions are met. In principle, this relation opens up the possibility of learning about the dynamics of 4D gauge theories thr

Chelsea L. MacLeod, Christopher S. Kochanek, Eric Agol

We present the first resolved mid-IR (11 micron) observations of the four-image quasar lens H1413+117 using the Michelle camera on Gemini North. All previous observations (optical, near-IR, and radio) of this lens show a &#34;flux anomaly,&#34; where the image flux ratios cannot be explained by a simple, central lens galaxy. We attempt to reproduce the mid-I