September 2006 arXiv papers — page 29

Alexander Knebe, Volkmar Wiessner

When analysing dark matter halos forming in cosmological N-body simulations it is common practice to obtain the density profile utilizing spherical shells. However, it is also known that the systems under investigation are far from spherical symmetry and rather follow a triaxial mass distribution. In this study we present an estimator for the error introduce

Rupali Chandar, S. Michael Fall, Bradley C. Whitmore

We present the age distributions for star clusters and individual stars in the Small Magellanic Cloud (SMC) based on data from the Magellanic Clouds Photometric Survey by Zaritsky and collaborators. The age distribution of the SMC clusters shows a steep decline, dN_{cluster}/dt \propto t^{-0.85\pm0.15}, over the period 10^7 < t <10^9 yr. This decline is esse

Thorsten Tepper García, Uta Fritze-von Alvensleben

We model the attenuation due to HI along a random line of sight (LOS) using differential distribution functions constrained from observations (Kim et al. 97) in a Monte Carlo fashion (Bershady et al. 99) as described in Tepper Garcia & Fritze-v.A. (in prep.). We generate an ensemble of thousands of lines of sight out to a given redshift z, each of them conta

Christine Allen, Edmundo Moreno, Barbara Pichardo

The effect of a barred potential (such as the one of the Milky Way) on the galactic orbits of forty-eight globular clusters for which absolute proper motions are known is studied. The orbital characteristics are compared with those obtained for the case of an axisymmetric galactic potential. Tidal radii are computed and discussed for both the better known ax

Alessandra Lamastra, Giorgio Matt, G. Cesare Perola

The BH mass (and the related Eddington ratio) in broad line AGN is usually evaluated by combining estimates (often indirect) of the BLR radius and of the FWHM of the broad lines, under the assumption that the BLR clouds are in Keplerian motion around the BH. Such an evaluation depends on the geometry of the BLR. There are two major options for the BLR config

Ralf S. Koehler, Peter Schuecker, Karl Gebhardt

The phases as well as the amplitudes of baryonic acoustic oscillations can be extracted out of a galaxy power spectrum and used as a standard ruler in a cosmological test. A non-oscillating phenomenological fitting function is used to extract the oscillatory part of the galaxy power spectrum and to disentangle phase information from amplitude information. Th

Judith G. Cohen, Scott Hsieh, Stanimir Metchev, S. G. Djorgovski

We have mosaiced 2MASS images to derive surface brightness profiles in JHK for 104 Galactic globular clusters. We fit these with King profiles, and show that the core radii are identical to within the errors for each of these IR colors, and are identical to the core radii at V in essentially all cases. We derive integrated light colors V-J, V-H, V-K_s, J-H a

Marie-Noelle Celerier

The currently available cosmological data yield, as a most striking result, that the expansion rate of the universe seems to be increasing at late times, contrary to the standard (zero cosmological constant) FLRW prediction. The usual explanation for this discrepancy is that a new component of the energy density of the universe, known as dark energy, dominat

J. L. Sanz, D. Herranz, M. Lopez-Caniego, F. Argueso

A new method is presented for the construction of a natural continuous wavelet transform on the sphere. It incorporates the analysis and synthesis with the same wavelet and the definition of translations and dilations on the sphere through the spherical harmonic coefficients. We construct a couple of wavelets as an extension of the flat Mexican Hat Wavelet t

P. J. Käpylä, M. J. Korpi, M. Stix, I. Tuominen

We study convective overshooting by means of local 3D convection calculations. Using a mixing length model of the solar convection zone (CZ) as a guide, we determine the Coriolis number (Co), which is the inverse of the Rossby number, to be of the order of ten or larger at the base of the solar CZ. Therefore we perform convection calculations in the range Co

F. Argueso, J. L. Sanz, R. B. Barreiro, D. Herranz

Cosmic microwave background (CMB) temperature anisotropies follow a Gaussian statistical distribution in the standard inflationary model, but there are non-Gaussian contributions due to astrophysical foregrounds. The detection of the non-Gaussian signal due to extragalactic point sources and its distinction from the possible intrinsic non-Gaussianity is an i

Mikhail V. Medvedev

The shock model of gamma-ray bursts (GRBs) contains two equipartition parameters: the magnetic energy density and the kinetic energy density of the electrons relative to the total energy density of the shock, &#34;epsilon_B&#34; and &#34;epsilon_e&#34;, respectively. These are free parameters within the model. Whereas the Weibel shock theory and numerical si

Surajit Dasgupta, A. R. Rao

We report the discovery of hard X-ray delays in the X-ray emission of the Seyfert 1 galaxy Mrk 110, based on a long XMM-Newton observation. Cross correlation between the X-ray light curves of different energy bands reveals an energy dependent delay ranging from a few minutes to an hour. We find that the energy spectrum can be modeled by Comptonization of dis

J. Pelt, J. M. Brooke, M. J. Korpi, I. Tuominen

It has recently been claimed that analysis of Greenwich sunspot data over 120 years reveals that sunspot activity clusters around two longitudes separated by 180 degrees (``active longitudes&#39;&#39;) with clearly defined differential rotation during activity cycles.In the present work we extend this critical examination of methodology to the actual Greenwi

E. Laurikainen, H. Salo, R. Buta, J. Knapen

Structural analysis has been performed for a sample of 15 Southern early-type disk galaxies, mainly S0s, using high resolution $K_s$-band images. The galaxies are mostly barred and many of them show multiple structures including bars and ovals, typical for S0s. The new images are of sufficient quality to reveal new detail on the morphology of the galaxies. F

Amara L. Graps, Simon F. Green, Neil McBride, J. A. M. McDonnell

In September 1996, a dust/debris detector: GORID was launched into the geostationary (GEO) region as a piggyback instrument on the Russian Express-2 telecommunications spacecraft. The instrument began its normal operation in April 1997 and ended its mission in July 2002. The goal of this work was to use GORID&#39;s particle data to identify and separate the

D. Stello, T. Arentoft, T. R. Bedding, M. Y. Bouzid

We report on an ambitious multi-site campaign aimed at detecting stellar variability, particularly solar-like oscillations, in the red giant stars in the open cluster M67 (NGC 2682). During the six-week observing run, which comprised 164 telescope nights, we used nine 0.6-m to 2.1-m class telescopes located around the world to obtain uninterrupted time-serie

Jeremy L. Martin, Matthew Morin, Jennifer D. Wagner

Let $T$ be an unrooted tree. The \emph{chromatic symmetric function} $X_T$, introduced by Stanley, is a sum of monomial symmetric functions corresponding to proper colorings of $T$. The \emph{subtree polynomial} $S_T$, first considered under a different name by Chaudhary and Gordon, is the bivariate generating function for subtrees of $T$ by their numbers of

Dan Israel, Eliezer Rabinovici

We study the decay of the unstable D-particle in three-dimensional anti-de Sitter space-time using worldsheet boundary conformal field theory methods. We test the open string completeness conjecture in a background for which the phase space available is only field-theoretic. This could present a serious challenge to the claim. We compute the emission of clos

Haluk Bingol

A dynamic memory model is proposed in which an agent ``learns&#39;&#39; a new agent by means of recommendation. The agents can also ``remember&#39;&#39; and ``forget&#39;&#39;. The memory size is decreased while the population size is kept constant. ``Fame&#39;&#39; emerged as a few agents become very well known in expense of the majority being completely fo

T. Shanks

We first compare the CMB lensing model of Seljak (1996) with the empirical model of Lieu & Mittaz (2005) to determine if the latter approach implies a larger effect on the CMB power-spectrum. We find that the empirical model gives significantly higher results for the magnification dispersion, assuming standard cosmological parameters. However, when the empir

Jason G. Ulery, Fuqiang Wang

Two-particle jet-like azimuthal correlations have revealed intriguing modifications to the away-side of high pt trigger particles in relativistic heavy-ion collisions. Three-particle jet-like azimuthal correlation and three-particle azimuthal cumulant have been analyzed in experiments in attempt to distinguish conical emission of jet-correlated particles fro

Jason G. Ulery, Fuqiang Wang

Jet-like three-particle azimuthal correlations can discriminate various physical scenarios that have been proposed to explain the observed strong modification to two-particle azimuthal correlations. The three-particle correlation analysis is notoriously difficult in heavy-ion collisions due to the large combinatoric backgrounds. We describe the general idea

Min-Su Shin, Edo Berger

We determine the relative rates of short GRBs in cluster and field early-type galaxies as a function of the age probability distribution of their progenitors, P(τ) \propto τ^n. This analysis takes advantage of the difference in the growth of stellar mass in clusters and in the field, which arises from the combined effects of the galaxy stellar mass function,

Martin Hohenadler, Georg Hager, Gerhard Wellein, Holger Fehske

Many-polaron systems with finite charge-carrier density are often encountered experimentally. However, until recently, no satisfactory theoretical description of these systems was available even in the framework of simple models such as the one-dimensional spinless Holstein model considered here. In this work, previous results obtained using numerical as wel

John Bueti

We discuss a planar variant of the Kakeya maximal function in the setting of a vector space over a finite field. Using methods from incidence combinatorics, we demonstrate that the operator is bounded from $L^p$ to $L^q$ when $1 \leq p \leq \frac{kn+k+1}{k(k+1)}$ and $1 \leq q \leq (n-k)p&#39;$.

Amalia K. Hicks, Erica Ellingson, Henk Hoekstra, Howard Yee

Results are presented from a detailed analysis of optical and X-ray observations of moderate-redshift galaxy clusters from the Canadian Network for Observational Cosmology (CNOC) subsample of the EMSS. The combination of extensive optical and deep X-ray observations of these clusters make them ideal candidates for multiwavelength mass comparison studies. X-r

Sigurdur Helgason

The X-ray transform on a compact symmetric space M is here inverted by means of an explicit inversion formula. The proof uses the conjugacy of the minimal closed geodesics in M and of the maximally curved totally geodesic spheres in M, proved in Math. Ann. 165 (1966), 309--317.

Kevin Heng, Richard McCray

We present a new formalism to describe the ratios and profiles of emission lines from hydrogen in Balmer-dominated shocks. We use this model to interpret the measured widths and ratios of broad and narrow H-alpha, H-beta and Ly-alpha emission lines in supernova remnants (SNRs). Our model results agree fairly well with those obtained previously by Chevalier,

Andreas Bierwage, Sadruddin Benkadda, Satoshi Hamaguchi, Masahiro Wakatani

The nonlinear evolution of resistive double tearing modes (DTMs) with safety factor values q=1 and q=3 is studied in a reduced cylindrical model of a tokamak plasma. We focus on cases where the resonant surfaces are a small distance apart. Recent numerical studies have shown that in such configurations high-m modes are strongly unstable. In this paper, it is

M. Bernardi

Early-type galaxy velocity dispersions and luminosities are correlated. The correlation estimated in local samples (< 100 Mpc) differs from that measured more recently in the SDSS. This is true even when systematics in the SDSS photometric and spectroscopic parameters have been accounted-for. We show that this is also true for the ENEAR sample if galaxy lumi

M. Bernardi, R. K. Sheth, E. Tundo, J. B. Hyde

It is common to estimate black hole abundances by using a measured correlation between black hole mass and another more easily measured observable such as the velocity dispersion or luminosity of the surrounding bulge. The correlation is used to transform the distribution of the observable into an estimate of the distribution of black hole masses. However, d

E. Tundo, M. Bernardi, J. B. Hyde, R. K. Sheth

Black hole masses are tightly correlated with the stellar velocity dispersions of the bulges which surround them, and slightly less-well correlated with the bulge luminosity. It is common to use these correlations to estimate the expected abundance of massive black holes. This is usually done by starting from an observed distribution of velocity dispersions

Carla Figueira de Morisson Faria, Andreas Fring

We provide a reviewlike introduction into the quantum mechanical formalism related to non-Hermitian Hamiltonian systems with real eigenvalues. Starting with the time-independent framework we explain how to determine an appropriate domain of a non-Hermitian Hamiltonian and pay particular attention to the role played by PT-symmetry and pseudo-Hermiticity. We d

Ruben Flores-Mendieta, Christoph P. Hofmann

The baryon axial vector current is computed at one-loop order in heavy baryon chiral perturbation theory in the large-N_c limit, where N_c is the number of colors. Loop graphs with octet and decuplet intermediate states cancel to various orders in N_c as a consequence of the large-N_c spin-flavor symmetry of QCD baryons. These cancellations are explicitly sh

Mikhail Khovanov, Richard Thomas

We argue that various braid group actions on triangulated categories should be extended to projective actions of the category of braid cobordisms and illustrate how this works in examples. We also construct actions of both the affine braid group and the braid cobordism category on the derived category of coherent sheaves on the cotangent bundle to the full f

Pascal Grange, Sakura Schafer-Nameki

Various approaches to T-duality with NSNS three-form flux are reconciled. Non-commutative torus fibrations are shown to be the open-string version of T-folds. The non-geometric T-dual of a three-torus with uniform flux is embedded into a generalized complex six-torus, and the non-geometry is probed by D0-branes regarded as generalized complex submanifolds. T

Marcus Mueller, Kirill Katsov, Michael Schick

We discuss the role coarse-grained models play in the investigation of the structure and thermodynamics of bilayer membranes, and we place them in the context of alternative approaches. Because they reduce the degrees of freedom and employ simple and soft effective potentials, coarse-grained models can provide rather direct insight into collective phenomena

Adam C. Lichtl

A previously-proposed method of constructing spatially-extended gauge-invariant three-quark operators for use in Monte Carlo lattice QCD calculations is tested, and a methodology for using these operators to extract the energies of a large number of baryon states is developed. This work is part of a long-term project undertaken by the Lattice Hadron Physics

Stefan Kettemann, Eduardo R. Mucciolo

Nonmagnetic disorder is shown to quench the screening of magnetic moments in metals, the Kondo effect. The probability that a magnetic moment remains free down to zero temperature is found to increase with disorder strength. Experimental consequences for disordered metals are studied. In particular, it is shown that the presence of magnetic impurities with a

Dominic Horsman, Vlatko Vedral

The formalism of Deutsch and Hayden is a useful tool for describing quantum mechanics explicitly as local and unitary, and therefore quantum information theory as concerning a "flow" of information between systems. In this paper we show that these physical descriptions of flow are unique, and develop the approach further to include the measurement interactio

T. Koide, G. S. Denicol, Ph. Mota, T. Kodama

We present a new formalism for the theory of relativistic dissipative hydrodynamics. Here, we look for the minimal structure of such a theory which satisfies the covariance and causality by introducing the memory effect in irreversible currents. Our theory has a much simpler structure and thus has several advantages for practical purposes compared to the Isr

Zaza Osmanov, Andria D. Rogava, Gianluigi Bodo

To investigate the efficiency of centrifugal acceleration of particles as a possible mechanism for the generation of ultra-high $γ$-ray nonthermal emission from TeV blazars, we study the centrifugal acceleration of electrons by rotating magnetic field lines, for an extended range of inclination angles and determine the maximum Lorentz factors $γ_{max}$ attai

Rosa Doran, Francisco S. N. Lobo, Paulo Crawford

The Schwarzschild solution has played a fundamental conceptual role in general relativity, and beyond, for instance, regarding event horizons, spacetime singularities and aspects of quantum field theory in curved spacetimes. However, one still encounters the existence of misconceptions and a certain ambiguity inherent in the Schwarzschild solution in the lit

Masudul Haque, Oleksandr Zozulya, Kareljan Schoutens

We present analytic and numerical calculations on the bipartite entanglement entropy in fractional quantum Hall states of the fermionic Laughlin sequence. The partitioning of the system is done both by dividing Landau level orbitals and by grouping the fermions themselves. For the case of orbital partitioning, our results can be related to spatial partitioni

I. L. Buchbinder, A. Fotopoulos, A. C. Petkou, M. Tsulaia

We propose a method of construction of a cubic interaction in massless Higher Spin gauge theory both in flat and in AdS space-times of arbitrary dimensions. We consider a triplet formulation of the Higher Spin gauge theory and generalize the Higher Spin symmetry algebra of the free model to the corresponding algebra for the case of cubic interaction. The gen

S. Mori, K. Kitsukawa, M. Hisakado

We show how to analyze and interpret the correlation structures, the conditional expectation values and correlation coefficients of exchangeable Bernoulli random variables. We study implied default distributions for the iTraxx-CJ tranches and some popular probabilistic models, including the Gaussian copula model, Beta binomial distribution model and long-ran

O. S. Barisic

A new numerical method is proposed for determining the low-frequency dynamics of the charge carrier coupled to the deformable quantum lattice. As an example, the polaron band structure is calculated for the one-dimensional Holstein model. The adiabatic limit on the lattice, which cannot be reached by other approaches, is investigated. In particular, an accur

Eugene V. Sukhorukov, Vadim V. Cheianov

We address the recently-observed unexpected behavior of Aharonov-Bohm oscillations in the electronic Mach-Zehnder interferometer that was realized experimentally in a quantum Hall system [1]. We argue that the measured lobe structure in the visibility of oscillations and the phase rigidity result from a strong long-range interaction between two adjacent coun

Vania Conan, Jeremie Leguay, Timur Friedman

Prior work on routing in delay tolerant networks (DTNs) has commonly made the assumption that each pair of nodes shares the same inter-contact time distribution as every other pair. The main argument in this paper is that researchers should also be looking at heterogeneous inter-contact time distributions. We demonstrate the presence of such heterogeneity in

L. Benfatto, C. Castellani, T. Giamarchi

In layered superconductors with small interlayer Josephson coupling vortex-antivortex phase fluctuations characteristic of quasi two-dimensional (2D) Kosterlitz-Thouless (KT) behavior are expected to be observable at some energy scale $T_d$. While in the 2D case $T_d$ is uniquely identified by the KT temperature $T_{KT}$ where the universal value of the supe

K. Manouchehri, J. B. Wang

Quantum random walks are shown to have non-intuitive dynamics, which makes them an attractive area of study for devising quantum algorithms for well-known classical problems as well as those arising in the field of quantum computing. In this work we propose a novel scheme for the physical implementation of a discrete-time quantum random walk using laser exci

Benjamin Texier, Kevin Zumbrun

Motivated by physical and numerical observations of time oscillatory ``galloping&#39;&#39;, ``spinning&#39;&#39;, and ``cellular&#39;&#39; instabilities of detonation waves, we study Poincaré--Hopf bifurcation of traveling-wave solutions of viscous conservation laws. The main difficulty is the absence of a spectral gap between oscillatory modes and essential

Ignacio J. General, Stephen R. Cotanch, Felipe J. Llanes-Estrada

An effective Coulomb gauge Hamiltonian, H_eff, is used to calculate the light (u-ubar-g), strange (s-sbar-g) and charmed (c-cbar-g) hybrid meson spectra. For the same two parameter H_eff providing glueball masses consistent with lattice results and a good description of the observed u,d,s and c quark mesons, a large-scale variational treatment predicts the l

H. Hansen, W. M. Alberico, A. Beraudo, A. Molinari

We investigate the properties of scalar and pseudo-scalar mesons at finite temperature and quark chemical potential in the framework of the Nambu-Jona-Lasinio (NJL) model coupled to the Polyakov loop (PNJL model) with the aim of taking into account features of both chiral symmetry breaking and deconfinement. The mesonic correlators are obtained by solving th

Spyros D. Avramis, Konstadinos Sfetsos, Dimitrios Zoakos

We consider the interaction of a heavy quark-antiquark pair moving in N=4 SYM plasma in the presence of non-vanishing chemical potentials. Of particular importance is the maximal length beyond which the interaction is practically turned off. We propose a simple phenomenological law that takes into account the velocity dependence of this screening length beyo

Monwhea Jeng, Geoffroy Piroux, Philippe Ruelle

We compute the lattice 1-site probabilities, on the upper half-plane, of the four height variables in the two-dimensional Abelian sandpile model. We find their exact scaling form when the insertion point is far from the boundary, and when the boundary is either open or closed. Comparing with the predictions of a logarithmic conformal theory with central char

Marcos Curty, Lucy Liuxuan Zhang, Hoi-Kwong Lo, Norbert Lütkenhaus

We investigate limitations imposed by sequential attacks on the performance of differential-phase-shift quantum key distribution protocols that use pulsed coherent light. In particular, we analyze two sequential attacks based on unambiguous state discrimination and minimum error discrimination, respectively, of the signal states emitted by the source. Sequen

Rohini M. Godbole, Sabine Kraml, Saurabh D. Rindani, Ritesh K. Singh

We discuss the use of fermion polarization for studying neutral Higgs bosons at a photon collider. To this aim we construct polarization asymmetries which can isolate the contribution of a Higgs boson $ϕ$ in $γγ\to f \bar f$, $f=τ/t$, from that of the QED continuum. This can help in getting information on the $γγϕ$ coupling in case $ϕ$ is a CP eigenstate. We

Winston Fairbairn

We study the coupling of massive fermions to the quantum mechanical dynamics of spacetime emerging from the spinfoam approach in three dimensions. We first recall the classical theory before constructing a spinfoam model of quantum gravity coupled to spinors. The technique used is based on a finite expansion in inverse fermion masses leading to the computati

Julien Larena, Thomas Buchert, Jean-Michel Alimi

Regionally averaged relativistic cosmologies have recently been considered as a possible explanation for the apparent late time acceleration of the Universe. This contribution reports on a mean field description of the backreaction in terms of a minimally coupled regionally homogeneous scalar field evolving in a potential, then giving a physical origin to th

Ian G. McCarthy, Richard G. Bower, Michael L. Balogh

The universal baryonic mass fraction (Omega_b/Omega_m) can be sensitively constrained using X-ray observations of galaxy clusters. In this paper, we compare the baryonic mass fraction inferred from measurements of the cosmic microwave background with the gas mass fractions (f_gas) of a large sample of clusters taken from the recent literature. In systems coo

J. Kokalj, P. Prelovsek

The validity of the Luttinger sum rule is considered for finite systems of interacting electrons, where the Fermi volume is determined by location of zeroes of Green&#39;s function. It is shown that the sum rule in the paramagnetic state is evidently violated within the planar t-J model at low doping while for the related Hubbard model, even in the presence

A. Yu. Nikitin, F. Lopez-Tejeira, L. Martin-Moreno

The scattering of surface plasmons polaritons by a one-dimensional defect of the surface is theoretically studied, by means of both Rayleigh and modal expansions. The considered defects are either relief perturbations or variations in the permittivity of the metal. The dependence of transmission, reflection and out-of-plane scattering on parameters defining

Yi-Fu Cai, Hong Li, Yun-Song Piao, Xinmin Zhang

In this paper we study the duality in two-field Quintom models of Dark Energy. We find that an expanding universe dominated by Quintom-A field is dual to a contracting universe with Quintom-B field.

by C. -M. Jen, P. Chang, K. Abe, K. Abe

We report improved measurements of $B$ to pseudoscalar-vector decays containing an $\omega$ meson in the final states. Our results are obtained from a data sample that contains $388\times 10^{6}$ $B\bar{B}$ pairs accumulated at the $\Upsilon(4S)$ resonance, with the Belle detector at the KEKB asymmetric-energy $e^+ e^-$ collider. We measure the following bra

Jean-Marie Lescure

In a earlier work of Claire Debord and the author, a notion of noncommutative tangent space isdefined for a conical pseudomanifold and the Poincaré duality in $K$-theory is proved between this space and the pseudomanifold. The present paper continues this work. We show that an appropriate and natural presentation of the notion of symbols on a manifold genera

Xiao-Song Wang

We suppose that vacuum is filled with a kind of continuously distributed matter which may be called the $\Omega(1)$ substratum, or the electromagnetic aether. Suppose that the time scale of a macroscopic observer is very large compares to the the Maxwelllian relaxation time of the $\Omega(1)$ substratum. Thus, the macroscopic observer concludes that the $\Om

James Cheney, Christian Urban

Nominal logic is an extension of first-order logic which provides a simple foundation for formalizing and reasoning about abstract syntax modulo consistent renaming of bound names (that is, alpha-equivalence). This article investigates logic programming based on nominal logic. We describe some typical nominal logic programs, and develop the model-theoretic,

R. Sánchez, G. Platero, R. Aguado, E. Cota

Pauli exclusion principle can lead to a supression of transport through double quantum dots, even if both quantum dots are connected by a resonant driving ac field. In this work, we study how this effect, known as spin blockade, can be removed by means of the influence of the driving field on the contacts to the leads.

Zhongzhi Zhang, Shuigeng Zhou

In this paper, by both simulations and theoretical predictions we study two and three node (or degree) correlations in random Apollonian network (RAN), which have small-world and scale-free topologies. Using the rate equation approach under the assumption of continuous degree, we first give the analytical solution for two node correlations, expressed by aver

Shu Chen, Li Wang, Yupeng Wang

We study the ground-state properties of frustrated Heisenberg ferrimagnetic ladders with antiferromagnetic exchange interactions and two types of alternating sublattice spins. In the limit of strong rung couplings, we show that the mixed spin-1/2 and spin-1 ladders can be systematically mapped onto a spin-1/2 Heisenberg model with additional next-nearest-nei

Dmitry A. Berdinsky, Iskander A. Taimanov

We study the generalization of the Willmore functional for surfaces in the three-Heisenberg group. Its construction is based on the spectral theory of the Dirac operator coming to the Weierstrass representation of surfaces (see math.DG/0503707). By using surfaces of revolution we demonstrate that it resembles the Willmore functional for surfaces in the Eucli

E. Z. Meilikhov, R. M. Farzetdinova

Nanosized spherical system of magnetic moments interacting indirectly via the RKKY mechanism is studied. The interaction energy that determines the temperature of the ferromagnetic ordering, depends strongly on the system size. Obtained in the mean-field approximation, dimensional and concentration dependencies of the Curie temperature testify to the necessi

Paulsamy Muruganandam, Gerson Francisco, Marcio de Menezes, Fernando F. Ferreira

The analysis of one-, two-, and three-dimensional coupled map lattices is here developed under a statistical and dynamical perspective. We show that the three-dimensional CML exhibits low dimensional behavior with long range correlation and the power spectrum follows $1/f$ noise. This approach leads to an integrated understanding of the most important proper

K. L. McDonald, B. H. J. McKellar

We investigate the quark-lepton symmetric gauge group in five dimensions, with the gauge symmetry broken by a combination of orbifold compactification of the extra dimension and the Higgs mechanism. The gauge sector of the model is investigated and contrasted with the four dimensional case. We obtain lower bounds on the mass of the exotic gauge bosons, the i

Y. M. Chiang, S. J. Feng

We investigate the growth of the Nevanlinna Characteristic of f(z+η) for a fixed ηin this paper. In particular, we obtain a precise asymptotic relation between T(r,f(z+η) and T(r,f), which is only true for finite order meromorphic functions. We have also obtained the proximity function and pointwise estimates of f(z+η)/f(z) which is a version of discrete ana

Bin Jiang

This paper aims to measure the efficiency of urban street networks (a kind of complex networks) from the perspective of the multidimensional chain of connectivity (or flow). More specifically, we define two quantities: flow dimension and flow capacity, to characterize structures of urban street networks. To our surprise for the topologies of urban street net

Tsz Ho Chan

We generalize Dirichlet&#39;s diophantine approximation theorem to approximating any real number $α$ by a sum of two rational numbers $\frac{a_1}{q_1} + \frac{a_2}{q_2}$ with denominators $1 \leq q_1, q_2 \leq N$. This turns out to be related to the congruence equation problem $x y \equiv c \pmod q$ with $1 \leq x, y \leq q^{1/2 + ε}$.

Satoshi Sunada, Takahisa Harayama

We study theoretically and numerically the effect of rotation on resonant frequencies of microcavities in a rotating frame of reference. Cavity rotation causes the shifts of the resonant frequencies proportional to the rotation rate if it is larger than a certain value. Below the value, a region of rotation rate exists where there is no resulting the frequen

A. E. Koshelev, Yu. I. Latyshev, M. Konczykowski

We study theoretically and experimentally influence of pancake vortices on motion of the Josephson vortex lattice in layered high-temperature superconductors. Mobility of the Josephson vortices in layered superconductors is strongly suppressed by small amount of pancake-vortex stacks. Moving Josephson vortex lattice forces oscillating zigzag deformation of t

Alexander Pechen, Herschel Rabitz

A non-equilibrium, generally time-dependent, environment whose form is deduced by optimal learning control is shown to provide a means for incoherent manipulation of quantum systems. Incoherent control by the environment (ICE) can serve to steer a system from an initial state to a target state, either mixed or in some cases pure, by exploiting dissipative dy

Timothy C. Jarrett, Alexandra Olaya-Castro, Neil F. Johnson

Information about quantum phase transitions in conventional condensed matter systems, must be sought by probing the matter system itself. By contrast, we show that mixed matter-light systems offer a distinct advantage in that the photon field carries clear signatures of the associated quantum critical phenomena. Having derived an accurate, size-consistent Ha

Wen-ge Wang

We study a quantum theory based on two assumptions: In the intrinsic frame of reference of an isolated, macroscopic system, (i) the system has no global motion and is not entangled with any other system, (ii) time evolution of statevectors of systems outside the system satisfy Schrödinger equation. A process of collision-type interaction between a microscopi

Zeqian Chen

It is shown that `bipartite&#39; wave functions can present a mathematical formalism of quantum theory for a single particle, in which the associated Schrödinger&#39;s wave functions correspond to those `bipartite&#39; wave functions of product forms. This extension of Schrödinger&#39;s form establishes a mathematical expression of wave-particle duality and

Y. -J. Han, X. J. Ren, Y. C. Wu, G. -C. Guo

Many of the properties of the partial transposition are not clear so far. Here the number of the negative eigenvalues of K(T)(the partial transposition of K) is considered carefully when K is a two-partite state. There are strong evidences to show that the number of negative eigenvalues of K(T) is N(N-1)/2 at most when K is a state in Hilbert space N*N. For

Cyril Branciard, Nicolas Gisin, Norbert Lutkenhaus, Valerio Scarani

This is a study of the security of the Coherent One-Way (COW) protocol for quantum cryptography, proposed recently as a simple and fast experimental scheme. In the zero-error regime, the eavesdropper Eve can only take advantage of the losses in the transmission. We consider new attacks, based on unambiguous state discrimination, which perform better than the

Ozlem Yesiltas, Ramazan Sever

Exact solutions of Schrodinger equation for PT-/non-PT-symmetric and non-Hermitian Morse and Poschl-Teller potentials are obtained with the position-dependent effective mass by applying a point canonical transformation method. Three kinds of mass distributions are used in order to construct exactly solvable target potentials and obtain energy spectrum and co

Xiao-Qiang Xi, W. M. Liu

Basing on the calculation of all the pairwise entanglement in the $n$ ($n \leq 6$)-qubit Heisenberg XX open chain with system impurity, we find an important result: pairwise entanglement can only be transferred through entangled pair. The non-nearest pairwise entanglement will has the possibility to exist as long as there has even number qubit in their middl

J. L. Herraiz, S. Espana, J. J. Vaquero, M. Desco

Small animal PET scanners require high spatial resolution and good sensitivity. To reconstruct high-resolution images in 3D-PET, iterative methods, such as OSEM, are superior to analytical reconstruction algorithms, although their high computational cost is still a serious drawback. The higher performance of modern computers could make iterative image recons

S. Vaitheeswaran, D. Thirumalai

We investigate the solvation of methane and methane decorated with charges in spherically confined water droplets. Free energy profiles for a single methane molecule in droplets, ranging in diameter D, from 1 to 4 nm, show that the droplet surfaces are strongly favorable as compared to the interior. From the temperature dependence of the free energy in D=3 n

A. W. Beckwith

We examine how ICE CUBE is impacted via definite observational limits, a potentially serious flaw in estimated collection ability as predicted by a short fall in Monte Carlo simulations, and a datum that the CP violations connected with Baryogenesis are not predicted by SUSY accurately. All these considerations, plus the known datum that water is a superior

Elena Ramirez Barrios, Juan G. Diaz Ochoa

The definition of preferences assigned to individuals is a concept that concerns many disciplines, from economics, with the search of an acceptable outcome for an ensemble of individuals, to decision making an analysis of vote systems. We are concerned in the phenomena of good selection and economic fairness. In Arrow&#39;s theorem this situation is expresse

Nicolas Vuillerme, Olivier Chenu, Jacques Demongeot, Yohan Payan

Proprioception is comprised of sensory input from several sources including muscle spindles, joint capsule, ligaments and skin. The purpose of the present experiment was to investigate whether the central nervous system was able to integrate an artificial biofeedback delivered through electrotactile stimulation of the tongue to improve proprioceptive acuity

Tobias Kretz, Michael Schreckenberg

In this paper a model of pedestrian motion is presented. As application its parameters are fitted to one run in a primary school evacuation exercise. Simulations with these parameters are compared to further runs during the same exercise.

Maria K. Koleva

Major revision of the thermodynamics is made in order to provide rigorous fundament for functional diversity of holistic type. It turns out that the new approach ensures reproducibility of the information as well.

A. Sulaksono, T. Mart

The effects of the symmetry energy softening of the relativistic mean field (RMF) models on the properties of matter with neutrino trapping are investigated. It is found that the effects are less significant than those in the case without neutrino trapping. The weak dependence of the equation of state on the symmetry energy is shown as the main reason of thi

K. Morawetz

It is shown that the collision integral describing the nonlocal character of collisions leads to the same mean-field fluctuations as proposed by Boltzmann-Langevin pictures. It is argued that this appropriate collision integral contains the fluctuation-dissipation theorems in equilibrium itself and therefore there is no need to assume additionally stochastic

W. Z. Jiang

The role of the isoscalar hyperon Lambda in probing the density dependence of the nuclear symmetry energy is studied in multi-Lambda hypernuclei, hyperon-rich matter and neutron stars in relativistic models. Relationships between the properties of three types of objects and the neutron thickness in 208Pb are established with respect to the isoscalar-isovecto

Rodrigo A. Vicencio, Joachim Brand, Sergej Flach

We study the transport of atoms across a localized Bose-Einstein condensate in a one-dimensional optical lattice. For atoms scattering off the condensate we predict total reflection as well as full transmission for certain parameter values on the basis of an exactly solvable model. The findings of analytical and numerical calculations are interpreted by a tu