September 2009 arXiv papers — page 28

Roland Diel, Guillaume Voisin

We consider a one-dimensional diffusion in a stable Lévy environment. We show that the normalized local time process refocused at the bottom of the standard valley with height $\log t$, $(L_X(t,\mathfrak m_{\log t}+x)/t,x\in \R)$, converges in law to a functional of two independent Lévy processes conditioned to stay positive. To prove this result, we show th

Jorgen Rasmussen

The near-horizon geometry of the extremal four-dimensional Kerr black hole and certain generalizations thereof has an SL(2,R) x U(1) isometry group. Excitations around this geometry can be controlled by imposing appropriate boundary conditions. For certain boundary conditions, the U(1) isometry is enhanced to a Virasoro algebra. Here, we propose a free-field

Kunio Kaneta, Yoshiharu Kawamura

We study the origin of fermion mass hierarchy and flavor mixing in a Lifshitz type extension of the standard model including an extra scalar field. We show that the hierarchical structure can originate from renormalizable interactions. In contrast to the Froggatt-Nielsen mechanism, the higher the dimension of associated operators, the heavier the fermion mas

Dong-Ling Deng, Jing-Ling Chen, Zi-Sui Zhou

We introduce a fresh scheme based on the local hidden variable models to quantify nonlocality for arbitrarily high-dimensional quantum systems. Our scheme explores the minimal amount of white noise that must be added to the system in order to make the system local and realistic. Moreover, the scheme has a clear geometric significance and is numerically compu

Jaroslaw A. Nowak

Using high statistics samples of charged current interactions, MiniBooNE reports a model independent measurement of the single charged pion production to quasi-elastic cross section ratio on mineral oil without corrections for pion re-interactions in the target nucleus. The result is provided as a function of neutrino energy in the range 0.4 GeV < E < 2.4 Ge

M. Aftabuzzaman, A. K. M. A. Islam, S. H. Naqib

We present results of ab-initio calculations of the electronic band structure, lattice dynamical properties, and elastic constants of LaOFeAs, the parent compound of the recently discovered superconducting iron-oxypnictide (LaO1-xFxFeAs). The total and partial electronic density of states (EDOS) of the undoped LaOFeAs (in the insulating or metallic state) ar

Andrés Santos

A recent paper [I. Klebanov et al. \emph{Mod. Phys. Lett. B} \textbf{22} (2008) 3153; arXiv:0712.0433] claims that the exact solution of the Percus-Yevick (PY) integral equation for a system of hard spheres plus a step potential is obtained. The aim of this paper is to show that Klebanov et al.&#39;s result is incompatible with the PY equation since it viola

H. B. Ann, Changbom Park, Yun-Young Choi

We search for isolated galaxies using a volume-limited sample of galaxies with 0.02< z < 0.04742 from SDSS DR7 supplemented by bright galaxies. We devise a diagnostic tool to select isolated galaxies in different environments using the projected separation (r_p) normalized by the virial radius of the nearest neighbor (r_{vir,nei}) and the local background de

Jackson DeBuhr, Eliot Quataert, Chung-Pei Ma, Philip Hopkins

We perform hydrodynamical simulations of major galaxy mergers using new methods for calculating the growth of massive black holes (BH) in galactic nuclei and their impact on the surrounding galaxy. We model BH growth by including a subgrid model for accretion produced by angular momentum transport on unresolved scales. The impact of the BHs radiation on surr

Yusuke Komatsu, Shohei Shimizu, Hidetoshi Shimodaira

Structural equation models and Bayesian networks have been widely used to study causal relationships between continuous variables. Recently, a non-Gaussian method called LiNGAM was proposed to discover such causal models and has been extended in various directions. An important problem with LiNGAM is that the results are affected by the random sampling of th

Xiaosong Wu, Yike Hu, Ming Ruan, Nerasoa K Madiomanana

The quantum Hall effect, with a Berry&#39;s phase of $π$ is demonstrated here on a single graphene layer grown on the C-face of 4H silicon carbide. The mobility is $\sim$ 20,000 cm$^2$/V$\cdot$s at 4 K and ~15,000 cm$^2$/V$\cdot$s at 300 K despite contamination and substrate steps. This is comparable to the best exfoliated graphene flakes on SiO$_2$ and an o

Yang Bai, Patrick J. Fox

It is usually assumed that dark matter direct detection is sensitive to a large fraction of the dark matter (DM) velocity distribution. We propose an alternative form of dark matter-nucleus scattering which only probes a narrow range of DM velocities due to the existence of a resonance, a DM-nucleus bound state, in the scattering - resonant dark matter (rDM)

Wentian Li, Annette Lee, Peter K Gregersen

Background: Regions with copy number variations (in germline cells) or copy number alteration (in somatic cells) are of great interest for human disease gene mapping and cancer studies. They represent a new type of mutation and are larger-scaled than the single nucleotide polymorphisms. Using genotyping microarray for copy number variation detection has beco

Yang Song, Hanan Dery

We present a technique to calculate the spin relaxation of hot electrons during their energy thermalization in the Gamma-valley of zinc-blende semiconductors. The results of this model match recent experimental data and they can be used to check the applicability of spin related boundary conditions across a semiconductor/ferromagnet junction in reverse bias

Teng Zhang, Arthur Szlam, Gilad Lerman

We describe the Median K-Flats (MKF) algorithm, a simple online method for hybrid linear modeling, i.e., for approximating data by a mixture of flats. This algorithm simultaneously partitions the data into clusters while finding their corresponding best approximating l1 d-flats, so that the cumulative l1 error is minimized. The current implementation restric

Jacob Chakareski, Pascal Frossard, Hervé Kerivin, Jimmy Leblet

We consider two capacity problems in P2P networks. In the first one, the nodes have an infinite amount of data to send and the goal is to optimally allocate their uplink bandwidths such that the demands of every peer in terms of receiving data rate are met. We solve this problem through a mapping from a node-weighted graph featuring two labels per node to a

Andreas Fuhrer

The pion and nucleon mass differences generate a very pronounced cusp in the photoproduction reaction of a single pion on the nucleon. A nonrelativistic effective field theory to describe this reaction is constructed. The approach is rigorous in the sense that it is an effective field theory with a consistent power counting scheme. Expressions for the S- and

Sriram Prasath E., Prasanta K. Panigrahi

A one way partial quantum bit commitment protocol is developed, using states with built-in classical correlation, completely independent of entanglement. It involves concealing information in a set of mutually non-orthogonal states and revealing it through measurements on a set of product states that are mutually orthogonal. Given $2^N$ choices to commit fro

Volodymyr Sushch

We study a discrete model of the SU(2) Yang-Mills equations on a combinatorial analog of $\Bbb{R}^4$. Self-dual and anti-self-dual solutions of discrete Yang-Mills equations are constructed. To obtain these solutions we use both techniques of a double complex and the quaternionic approach. Interesting analogies between instanton, anti-instanton solutions of

Hikari Kimura, R. P. Barber, S. Ono, Yoichi Ando

Direct measurements of the superconducting superfluid on the surface of vacuum-cleaved Bi2Sr2CaCu2O8(BSCCO) samples are reported. These measurements are accomplished via Josephson tunneling into the sample using a scanning tunneling microscope (STM) equipped with a superconducting tip. The spatial resolution of the STM of lateral distances less than the supe

Priyotosh Bandyopadhyay, Biplob Bhattacherjee, AseshKrishna Datta

The Higgs sector of the Universal Extra Dimensions (UED) has a rather involved setup. With one extra space dimension, the main ingredients to the construct are the higher Kaluza-Klein (KK) excitations of the Standard Model Higgs boson and the fifth components of the gauge fields which on compactification appear as scalar degrees of freedom and can mix with t

ChongGyu Lee

In 2006, Kawaguchi proved a lower bound for height of h(f(P)) when f is a regular affine automorphism of A^2, and he conjectured that a similar estimate is also true for regular affine automorphisms of A^n for n>2. In this paper we prove Kawaguchi&#39;s conjecture. This implies that Kawaguchi&#39;s theory of canonical heights for regular affine automorphisms

M. F. Michelon, A. Antonelli

We have developed a methodology to study the thermodynamics of order-disorder transformations in n-component substitutional alloys that combines nonequilibrium methods, which can efficiently compute free energies, with Monte Carlo simulations, in which configurational and vibrational degrees of freedom are simultaneously considered on an equal footing basis.

Alberto Buzzoni, Emanuele Bertone, Miguel Chavez

We outline a new method to derive a &#34;snapshot&#34; metallicity estimate of stellar systems (providing one resolves at least the brightest part of the CMD) just on the basis of low-resolution (i.e., 6-8A FWHM) spectroscopy of a small stellar sample. Our method relies on the Fe5270 Lick index measurements and takes advantage of the special behavior of this

Nicoletta Cantarini, Victor G. Kac

The notion of an anti-commutative (resp. commutative) rigid superalgebra is a natural generalisation of the notion of a Lie (resp. Jordan) superalgebra. Intuitively rigidity means that small deformations of the product under the structural group produce an isomorphic algebra. In this paper we classify all linearly compact simple anti-commutative (resp. commu

Ofer Cohen, Gemma D. R. Attrill, Ward B. Manchester, Meredith J. Wills-Davey

On 13 February 2009, a coronal wave -- CME -- dimming event was observed in quadrature by the STEREO spacecraft. We analyze this event using a three-dimensional, global magnetohydrodynamic (MHD) model for the solar corona. The numerical simulation is driven and constrained by the observations, and indicates where magnetic reconnection occurs between the expa

O. Cohen, J. J. Drake, V. L. Kashyap, S. H. Saar

Since the first discovery of an extrasolar planetary system more than a decade ago, hundreds more have been discovered. Surprisingly, many of these systems harbor Jupiter-class gas giants located close to the central star, at distances of 0.1 AU or less. Observations of chromospheric &#39;hot spots&#39; that rotate in phase with the planetary orbit, and elev

Evan N. Kirby, Puragra Guhathakurta, Michael Bolte, Christopher Sneden

We present measurements of Fe, Mg, Si, Ca, and Ti abundances for 388 radial velocity member stars in the Sculptor dwarf spheroidal galaxy (dSph), a satellite of the Milky Way. This is the largest sample of individual alpha element (Mg, Si, Ca, Ti) abundance measurements in any single dSph. The measurements are made from Keck/DEIMOS medium-resolution spectra

Xin Liu, John Kountouriotis, Athina P. Petropulu, Kapil R. Dandekar

A cross-layer scheme, namely ALOHA With Collision Resolution (ALOHA-CR), is proposed for high throughput wireless communications in a cellular scenario. Transmissions occur in a time-slotted ALOHA-type fashion but with an important difference: simultaneous transmissions of two users can be successful. If more than two users transmit in the same slot the coll

Oleg V. Gendelman, Alexander V. Savin

The Letter addresses the relationship between hyperbolic equations of heat conduction and microscopic models of dielectrics. Effects of the non-stationary heat conduction are investigated in two one-dimensional models with conserved momentum: Fermi-Pasta-Ulam (FPU) chain and chain of rotators (CR). These models belong to different universality classes with r

C. Mancini, E. Daddi, A. Renzini, F. Salmi

We investigate the properties of 12 ultra-massive passively evolving early type galaxies (ETGs) at z_phot>1.4 in the COSMOS 2 deg^2 field. These 12 ETGs were selected as pBzKs, have accurate 1.4<= z_phot <=1.7,high Sersic index profiles typical of ellipticals, no detection at 24 micron, resulting in a complete ETG sample at M*>2.5x10^11 M_sun (Chabrier IMF).

Karl D. Gordon, Stefan Cartledge, Geoffrey C. Clayton

We present a sample of 75 extinction curves derived from FUSE far-ultraviolet spectra supplemented by existing IUE spectra. The extinction curves were created using the standard pair method based on a new set of dereddened FUSE+IUE comparison stars. Molecular hydrogen absorption features were removed using individualized H_2 models for each sightline. The ge

Yu. N. Ovchinnikov, I. M. Sigal

We derive the universal collapse law of degree 1 equivariant wave maps (solutions of the sigma-model) from the 2+1 Minkowski space-time,to the 2-sphere. To this end we introduce a nonlinear transformation from original variables to blowup ones. Our formal derivations are confirmed by numerical simulations.

Z. Thrailkill, S. Kennerly, A. Tyler, R. C. Ramos

The superconducting Josephson junction has been demonstrated to be a strong candidate for building quantum bits or &#34;qubits&#34; which are the components of a future quantum computer. In recent years, considerable theoretical and experimental effort have been focused on studying quantum properties of single qubits and two coupled solid-state qubits. We pr

Felix Braam, Juergen Reuter, Daniel Wiesler

Grand Unified Theories based on an E6 gauge group embed all Higgs- and matter fields within one 27 dimensional fundamental representation. In addition each 27 contains a right handed neutrino, an NMSSM-like standard model singlet and a pair of exotic particles, that couple quarks to leptons. The extended particle content spoils simple gauge unification as in

Jean-Philippe Cointet, Camille Roth

The blogosphere can be construed as a knowledge network made of bloggers who are interacting through a social network to share, exchange or produce information. We claim that the social and semantic dimensions are essentially co-determined and propose to investigate the co-evolutionary dynamics of the blogosphere by examining two intertwined issues: First, h

Alexander Fedotov, Frédéric Klopp

In the present paper, we derive a renormalization formula &#34;à la Hardy-Littlewood&#34; for the Gaussian exponential sums with an exact formula for the remainder term. We use this formula to describe the typical growth of the Gaussian exponential sums.

Sanghamitra Neogi, Gerald D. Mahan

The properties of the ground state of liquid $^4$He are studied using a correlated basis function of the form $\prod_{i<j} ψ(r_{ij})$. Here, $ψ(r)$ is chosen as the exact solution of the Schrödinger equation for two $^4$He atoms. A hard-sphere plus an attractive square well is used as the interaction potential between $^4$He atoms. The pair distribution func

Bernd A. Berg, Alexei Bazavov, Hao Wu

Deconfined regions in relativistic heavy ion collisions are limited to small volumes surrounded by a confined exterior. Here the geometry of a double layered torus is discussed, which allows for different temperatures in its two layers. This geometry enables one to approach the QCD continuum limit for small deconfined volumes with confined exteriors in a mor

Sergey K. Tolpygo, Denis Amparo

Currently, superconductor digital integrated circuits fabricated at HYPRES, Inc. can operate at clock frequencies of ~ 40 GHz. The circuits present multilayered structures containing tens of thousands of Nb/Al/AlOx/Nb Josephson junctions (JJs) of various sizes interconnected by four Nb wiring layers, resistors, and other circuit elements. In order to be oper

Constança Providência, João da Providência, Flávio Cordeiro, Masatoshi Yamamura

We present the exact solutions to the equations of the lowest energy states of the colored and color-symmetric sectors of the Bonn quark model, which is SU(3) symmetric and is defined in terms of an effective pairing force with $su(4)$ algebraic structure. We show that the groundstate of the model is not color symmetrical except for a narrow interval in the

N. Paar, G. Colo, E. Khan, D. Vretenar

A fully self-consistent microscopic framework for evaluation of nuclear weak-interaction rates at finite temperature is introduced, based on Skyrme functionals. The single-nucleon basis and the corresponding thermal occupation factors of the initial nuclear state are determined in the finite-temperature Skyrme Hartree-Fock model, and charge-exchange transiti

Diego A. R. Dalvit, Roberto Onofrio

We discuss the role of the proximity force approximation in deriving limits to the existence of Yukawian forces - predicted in the submillimeter range by many unification models - from Casimir force experiments using the sphere-plane geometry. Two forms of this approximation are discussed, the first used in most analyses of the residuals from the Casimir for

Manjari Bagchi, Alak Ray

The observed distribution of globular cluster binary radio pulsars in the eccentricity versus orbital period plane can be explained as a result of binary-single star interactions. Our numerical and analytical study hints that the highest eccentricity binaries in clusters are likely to be from exchange and/or merger of a single star with a binary component, w

Zhao Wang, Mariusz Zdrojek, Thierry Melin, Michel Devel

We present a detailed study of the static enhancement effects of electric charges in micron-length single-walled carbon nanotubes, using theoretically an atomic charge-dipole model and experimentally electrostatic force microscopy. We demonstrate that nanotubes exhibit at their ends surprisingly weak charge enhancements which decrease with the nanotube lengt

Juergen Reuter, Felix Braam

The Next-To-Minimal-Supersymmetric extension of the Standard Model (NMSSM) has been in the focus of extensive studies in the past two decades. In anticipation of the LHC era, the interest in automatized tools that can calculate collider signatures has grown. We present the implementation of the NMSSM into the event generator WHIZARD. In addition to a brief r

J. Gonzalez, J. Herrero

We study the properties of graphene wormholes in which a short nanotube acts as a bridge between two graphene sheets, where the honeycomb carbon lattice is curved from the presence of 12 heptagonal defects. By taking the nanotube bridge with very small length compared to the radius, we develop an effective theory of Dirac fermions to account for the low-ener

R. Caimmi

Different sequences of ellipsoids are represented on the ellipticity-rotation plane. The rotation parameter is defined as the ratio of kinetic energy related to the mean tangential equatorial velocity component to kinetic energy related to tangential equatorial component velocity dispersion and residual motions. Systems with isotropic stress tensor are consi

Syed T. Qaseem, Tareq Y. Al-Naffouri

A key feature in the design of any MAC protocol is the throughput it can provide. In wireless networks, the channel of a user is not fixed but varies randomly. Thus, in order to maximize the throughput of the MAC protocol at any given time, only users with large channel gains should be allowed to transmit. In this paper, compressive sensing based opportunist

Patrick O. Perry

Cross-validation (CV) is a popular method for model-selection. Unfortunately, it is not immediately obvious how to apply CV to unsupervised or exploratory contexts. This thesis discusses some extensions of cross-validation to unsupervised learning, specifically focusing on the problem of choosing how many principal components to keep. We introduce the latent

R. Angelini, G. Salvi, G. Ruocco

We studied the rheological behavior of a molecular solution composed of $α$-cyclodextrin, water and 4-methylpyridine, a liquid known to undergo inverse melting, at different temperatures and concentrations. The system shows a marked non-Newtonian behavior, exhibiting the typical signature of shear thickening. Specifically, a transition is observed from a New

Daniel Niewieczerzal, Czeslaw Oleksy, Andrzej Szczepkowicz

We perform detailed numerical simulations of field ion microscopy images of faceted crystals and compare them with experimental observations. In contrast to the case of crystals with a smooth surface, for a faceted topography we find extreme deformations of the ion image. Local magnification is highly inhomogeneous and may vary by an order of magnitude: from

Jan Germer, Wolfgang Hollik, Edoardo Mirabella, Maike K. Trenkel

We present the tree-level and next-to-leading order (NLO) electroweak (EW) contributions to squark-squark production at the Large Hadron Collider (LHC) within the framework of the Minimal Supersymmetric Standard Model (MSSM).

Stephanie M. LaMassa, Timothy M. Heckman, Andrew A. Ptak, Ann Hornschemeier

(abridged)The majority of Active Galactic Nuclei (AGN) suffer from significant obscuration by surrounding dust and gas. X-ray surveys in the 2-10 keV band will miss the most heavily-obscured AGN in which the absorbing column density exceeds $\sim10^{24}$cm$^{-2}$ (the Compton-thick AGN). It is therefore vital to know the fraction of AGN that are missed in su

Christian Hainzl, Enno Lenzmann, Mathieu Lewin, Benjamin Schlein

We prove finite-time blowup for spherically symmetric and negative energy solutions of Hartree-Fock and Hartree-Fock-Bogoliubov type equations, which describe the evolution of attractive fermionic systems (e. g. white dwarfs). Our main results are twofold: First, we extend the recent blowup result of [Hainzl and Schlein, Comm. Math. Phys. \textbf{287} (2009)

P Chang, E Quataert

In low-collisionality plasmas, anisotropic heat conduction due to a magnetic field leads to buoyancy instabilities for any nonzero temperature gradient. We study analogous instabilities in degenerate {\it collisional} plasmas, i.e., when the electron collision frequency is large compared to the electron cyclotron frequency. Although heat conduction is nearly

Mikael Kuusela, Jerry W. Lamsa, Eric Malmi, Petteri Mehtala

Close to one half of the LHC events are expected to be due to elastic or inelastic diffractive scattering. Still, predictions based on extrapolations of experimental data at lower energies differ by large factors in estimating the relative rate of diffractive event categories at the LHC energies. By identifying diffractive events, detailed studies on proton

H. Rampadarath, M. A. Garrett, T. Muxlow, G. I. G. Józsa

We present the results of VLBI and MERLIN observations of the massive disk galaxy IC 2497. Optical observations of IC 2497 revealed the existence of a giant emission nebula &#34;Hanny&#39;s Voorwerp&#34; in the proximity of the galaxy. Earlier short-track 18 cm observations with e-VLBI at 18 cm, detected a compact radio component (C1) at the centre of IC 249

S. Valencia, A. Gaupp, W. Gudat, Ll. Abad

A Mn valence instability on La2/3Ca1/3MnO3 thin films, grown on LaAlO3 (001)substrates is observed by x-ray absorption spectroscopy at the Mn L-edge and O K-edge. As-grown samples, in situ annealed at 800 C in oxygen, exhibit a Curie temperature well below that of the bulk material. Upon air exposure a reduction of the saturation magnetization, MS, of the fi

A. Zazunov, R. Egger, T. Jonckheere, T. Martin

For a general model of a mesoscopic multi-level quantum dot, we determine the necessary conditions for the existence of an anomalous Josephson current with spontaneously broken time-reversal symmetry. They correspond to a finite spin-orbit coupling, a suitably oriented Zeeman field, and the dot being a chiral conductor. We provide analytical expressions for

Elvan Ceyhan

We use the domination number of a parametrized random digraph family called proportional-edge proximity catch digraphs (PCDs) for testing multivariate spatial point patterns. This digraph family is based on relative positions of data points from various classes. We extend the results on the distribution of the domination number of proportional-edge PCDs, and

Jin-Hua Liu, Qian-Qian Shi, Hong-Lei Wang, Jon Links

For any translation-invariant quantum lattice system with a symmetry group G, we propose a practical and universal construction of order parameters which identify quantum phase transitions with symmetry-breaking order. They are defined in terms of the fidelity between a ground state and its symmetry-transformed counterpart, and are computed through tensor ne

Christophe Martayan

NGC6611, Trumpler 14, Trumpler 15, Trumpler 16, Collinder 232 are very young open clusters located in star-formation regions of the Eagle Nebula or the Carina in the MW, and NGC346 in the SMC. With different instrumentations and techniques, it was possible to detect and classify new Herbig Ae/Be stars, classical Be stars and to provide new tests / comparison

Emmanuel Prochasson, Emmanuel Morin, Christian Viard-Gaudin

Handwriting is an alternative method for entering texts which composed Short Message Services. However, a whole new language features the texts which are produced. They include for instance abbreviations and other consonantal writing which sprung up for time saving and fashion. We have collected and processed a significant number of such handwritten SMS, and

Emmanuel Ep Prochasson, Christian Viard-Gaudin, Emmanuel Morin

Handwriting is an alternative method for entering texts composing Short Message Services. However, a whole new language features the texts which are produced. They include for instance abbreviations and other consonantal writing which sprung up for time saving and fashion. We have collected and processed a significant number of such handwriting SMS, and used

Daniel R. Weisz, Evan D. Skillman, John M. Cannon, Andrew E. Dolphin

We use deep HST/ACS F555W and F814W photometry of resolved stars in the M81 Group dwarf irregular galaxy Ho II to study the hypothesis that the holes identified in the neutral ISM (HI) are created by stellar feedback. From the deep photometry, we construct color-magnitude diagrams (CMDs) and measure the star formation histories (SFHs) for stars contained in

Paolo Walter Cattaneo

The knowledge of capacitance in semiconductor micro-strip detectors is important for a correct design, simulation and understanding of the detectors. Analytical approaches can efficiently complement numerical methods providing quick results in the design phase. The conformal mapping method has proved to be the most effective analytical approach providing man

Michael Farber, Viktor Fromm

We study topology of configuration spaces of planar linkages having one leg of variable length. Such telescopic legs are common in modern robotics where they are used for shock absorbtion and serve a variety of other purposes. Using a Morse theoretic technique, we compute explicitly, in terms of the metric data, the Betti numbers of configuration spaces of t

Bodo L. Ziegler, Elif Kutdemir, Cristiano Da Rocha, Asmus Böhm

To understand the processes that build up galaxies we investigate the stellar structure and gas kinematics of spiral and irregular galaxies out to redshift 1. We target 92 galaxies in four cluster (z = 0.3 & 0.5) fields to study the environmental influence. Their stellar masses derived from multiband VLT/FORS photometry are distributed around but mostly belo

Benoit Fresse

The category of differential graded operads is a cofibrantly generated model category and as such inherits simplicial mapping spaces. The vertices of an operad mapping space are just operad morphisms. The 1-simplices represent homotopies between morphisms in the category of operads. The goal of this paper is to determine the homotopy of the operadic mapping

Jacopo Bechi

In this paper the quark zero modes creation effect is studied in the context of the AdS/QCD approach. This effect is generated, in presence of instantons, by a new that can be added in the bulk.

Galin N. Gyulchev, Stoytcho S. Yazadjiev

We investigate analytically gravitational lensing by charged, stationary, axially symmetric Kerr-Sen dilaton-axion black hole in the weak deflection limit. Approximate solutions to the lightlike equations of motion are present up to and including third-order terms in $M/b$, $a/b$ and $r_α/b$, where $M$ is the black hole mass, $a$ is the angular momentum, $r_

Hongsheng Zhang

The cosmic acceleration is one of the most significant cosmological discoveries over the last century. Following the more accurate data a more dramatic result appears: the recent analysis of the observation data (especially from SNe Ia) indicate that the time varying dark energy gives a better fit than a cosmological constant, and in particular, the equation

Ivana Ebrova, Bruno Jungwiert, Gabriela Canalizo, Nicola Bennert

Using N-body simulations of shell galaxies created in nearly radial minor mergers, we investigate the error of collision dating, resulting from the neglect of dynamical friction and of gradual disruption of the cannibalized dwarf.

Hylke B. J. Koers, Peter Tinyakov

We consider the dependence of ultra-high energy cosmic ray (UHECR) flux predictions on the choice of galaxy catalogue. We demonstrate that model predictions by Koers & Tinyakov (2009b), based on the so-called KKKST catalogue, are in good agreement with predictions based on the XSCz catalogue, a recently compiled catalogue that contains spectroscopic redshift

Sergey G Artyshev

A new way for finding analytical solutions of the three-dimensional sine-Gordon equation is presented. The method is based on the established relation between the solutions of the three-dimensional wave equation and solutions of the three-dimensional sine-Gordon equation. Some examples of the solutions thus obtained are show.

R. Hänninen, W. Schoepe

The critical velocity v_c for the onset of quantum turbulence in oscillatory flows of superfluid helium is universal and scales as v_c \sim \sqrt{\kappa\omega}, where \kappa is the circulation quantum and \omega is the oscillation frequency. This result can be derived from a general argument based on the "superfluid Reynolds number". Only the numerical prefa

Terry Rudolph

A simple construction is presented which allows computing the transition amplitude of a quantum circuit to be encoded as computing the permanent of a matrix which is of size proportional to the number of quantum gates in the circuit. This opens up some interesting classical monte-carlo algorithms for approximating quantum circuits.

S. Sanna, R. De Renzi, G. Lamura, C. Ferdeghini

We report about muSR measurements on SmFeAsO1-xFx which helped us to identify the signature of diluted ferromagnetic inclusions, ubiquitous in the iron pnictides. These impurities are characterized by a Curie temperature close to room temperature and they seem responsible for a non negligible magnetic relaxation of the implanted muons, that should not be con

Noriyuki Otsubo

We calculate the Beilinson regulators of motives associated to Fermat curves and express them by special values of generalized hypergeometric functions. As a result, we obtain surjectivity results of the regulator, which support the Beilinson conjecture on special values of L-functions.

Tigran G. Arshakian, Rainer Beck, Marita Krause, Dmitry Sokolff

Results from simulations of hierarchical structure formation cosmology provide a tool to develop an evolutionary model of regular magnetic fields coupled to galaxy formation and evolution. We use the dynamo theory to derive the timescales of amplification and ordering of magnetic fields in disk and puffy galaxies. Galaxies similar to the Milky Way formed the

Ewald Puchwein, Debora Sijacki, Volker Springel

There is compelling evidence that black holes (BHs) in cluster centers vigorously interact with their surroundings, indicating that any realistic model of cluster formation needs to account for these processes. Here we use high-resolution cosmological simulations of a large cluster and group sample to study how BHs affect their host systems. We focus on two

Wee Teck Gan, Benedict H. Gross, Dipendra Prasad

We consider several questions about restriction of representations of classical and metaplectic groups over local and global fields to subgroups, extending considerably the scope of the earlier work on $SO(n),SO(n-1)$. This includes Bessel and Fourier-Jacobi models too. We formulate several conjectures about these restriction problems involving root numbers

T. G. Philbin, C. Xiong, U. Leonhardt

The Casimir effect in an inhomogeneous dielectric is investigated using Lifshitz&#39;s theory of electromagnetic vacuum energy. A permittivity function that depends continuously on one Cartesian coordinate is chosen, bounded on each side by homogeneous dielectrics. The result for the Casimir stress is infinite everywhere inside the inhomogeneous region, a di

V. Suleimanov, A. Y. Potekhin, K. Werner

We present a new computer code for modeling magnetized neutron star atmospheres in a wide range of magnetic fields (10^{12} - 10^{15} G) and effective temperatures (3 \times 10^5 - 10^7 K). The atmosphere is assumed to consist either of fully ionized electron-ion plasmas or of partially ionized hydrogen. Vacuum resonance and partial mode conversion are taken

M. Revnivtsev, E. Churazov, K. Postnov, S. Tsygankov

We study power density spectra (PDS) of X-ray flux variability in binary systems where the accretion flow is truncated by the magnetosphere. PDS of accreting X-ray pulsars where the neutron star is close to the corotation with the accretion disk at the magnetospheric boundary, have a distinct break/cutoff at the neutron star spin frequency. This break can na

Eric Poisson

I present an overview of the methods involved in the computation of the scalar, electromagnetic, and gravitational self-forces acting on a point particle moving in a curved spacetime. For simplicity, the focus here will be on the scalar self-force. The lecture follows closely my review article on this subject published in Living Reviews in Relativity. I begi

Wee Teck Gan, Benedict H. Gross, Dipendra Prasad

In an earlier paper, we considered several restriction problems in the representation theory of classical groups over local and global fields. Assuming the Langlands-Vogan parameterization of irreducible representations, we formulated precise conjectures for the solutions of these restriction problems. In the local case, our conjectural answer is given in te

Martin Boutelier, Didier Barret, Yongfeng Lin, Gabriel Torok

The width (W), root mean squared amplitude (Rs) of lower and upper kHz quasi-periodic oscillations (QPOs) from accreting neutron stars vary with frequency. Similarly, the QPO frequency varies with the source count rate (S). Hence, the significance of a QPO, scaling as S x Rs^2/W^(1/2) will also depend on frequency. In addition, the significance also scales u

Johann Rafelski, Lance Labun, Yaron Hadad, Pisin Chen

Short review of riddles that lie at the intersection of quantum theory, particle physics and cosmology; dark energy as false vacuum; discussion of a possible detection experiment.

Vadim V. Cheianov, Olav Syljuasen, Boris L. Altshuler, Vladimir Fal&#39;ko

We show that a dilute ensemble of epoxy-bonded adatoms on graphene has a tendency to form a spatially correlated state accompanied by a gap in graphene&#39;s electron spectrum. This effect emerges from the electron-mediated interaction between adatoms with a peculiar $1/r^3$ distance dependence. The partial ordering transition is described by a random bond t

K. L. Lee, K. Bouadim, G. G. Batrouni, F. Hebert

We study the attractive fermionic Hubbard model on a honeycomb lattice using determinantal quantum Monte Carlo simulations. By increasing the interaction strength U (relative to the hopping parameter t) at half-filling and zero temperature, the system undergoes a quantum phase transition at 5.0 < U_c/t < 5.1 from a semi-metal to a phase displaying simultaneo

Ramaz Khomeriki, Jerome Leon

A long wavelength optical lattice is generated in a two-level medium by low-frequency contrapropagating beams. Then a short wave length gap soliton generated by evanescent boundary instability (supratransmission) undergoes a dynamics shown to obey the Newton equation of the parametrically driven pendulum, hence presenting extremely rich, possibly chaotic, dy

Ningning Hao, Wei Zhang, Zhigang Wang, Yupeng Wang

We study a bilayer two-dimension-electron-gas (2DEG) adjacent to a type-II superconductor thin film with a pinned vortex lattice. We find that with increasing interlayer tunneling, the system of half filling presents three phases: gapped phase-I (topological insulator), gapless critical phase-II (metal), and gapped phase-III (band insulator). The Hall conduc

Michel Jaffré

At hadron colliders, new massive particles can be searched for by the observation of high tranverse momentum objects forming high-mass resonances. Searches for additional massive vector bosons (W&#39;,Z&#39;), Randall-Sundrum gravitons and sneutrinos in R-parity violating scenarios are performed in dilepton, dijets and diboson final states. The most recent r

Otar Bakradze*, Zurab Alimbarashvili, Rusiko Janelidze

The paper investigates the ellipsometric method of measuring the magneto-optical parameter and optical constants in one experiment at affixed angle of the light incidence in ferromagnetics. The influence of the magnetization modulation on the change of ellipsometrical angles is shown. The method is considered for the geometries of polar, meridional and equat

T. Wenzler, S. K. Solanki, N. A. Krivova

Total solar irradiance reconstructed between 1978 and 2003 using solar surface magnetic field distributions is compared with three composites of total solar irradiance measurements. A good correspondence is found with the total solar irradiance composite from PMOD/WRC, with no bias between the three cycles. The agreement with the other composites (the ACRIM

Abdul Malik, Martin Bohm

This research work is based on the study of the longitudinal distribution of the most active sunspot zones on the photosphere. Sunspot data has been analyzed for 12 solar cycles (cycles 12-23) separately for northern and southern hemisphere, and the entire solar sphere. The timelongitude diagrams and their corresponding histograms have been plotted to probe

Stephen F King

We survey some of the recent promising developments in the search for the theory behind neutrino mass and tri-bimaximal mixing, and indeed all fermion masses and mixing. We focus in particular on models with discrete family symmetry and unification, and show how such models can also solve the SUSY flavour and CP problems. We also discuss the theoretical impl

Petra N. Schwer

We prove equivalence of certain axiom sets for affine buildings. Along the lines a purely combinatorial proof of the existence of a spherical building at infinity is given. As a corollary we obtain that ``being an affine building&#39;&#39; is independent of the metric structure of the space.