May 2008 arXiv papers — page 23

Carmen Caprau

We generalize the Khovanov-Rozansky cohomology for n=2 by means of a homogeneous potential that depends on two parameters, to obtain the universal Khovanov-Rozansky sl(2) link cohomology. This theory is equivalent to the universal foam sl(2) link cohomology, after tensoring both theories with appropriate rings.

Gastón A. Avila, Sergio Dain

An explicit 3-dimensional Riemannian metric is constructed which can be interpreted as the (conformal) sum of two Kerr black holes with aligned angular momentum. When the separation distance between them is large we prove that this metric has positive Ricci scalar and hence positive Yamabe invariant. This metric can be used to construct axially symmetric ini

E. G. Ferreiro

Thirty years ago, Matsui and Satz proposed the $J/ψ$ destruction as a signal of a Quark Gluon Plasma (QGP) formation, due to the Debye screening between the pair c-cbar. At the light of the recent experimental data, I review the different effects on $J/ψ$ production, from SPS to LHC energies, distinguishing between Cold Nuclear Matter (CNM) and QGP effects.

Constantinos Panagiotakopoulos, Petroula Tsampouka

We identify the classical Perceptron algorithm with margin as a member of a broader family of large margin classifiers which we collectively call the Margitron. The Margitron, (despite its) sharing the same update rule with the Perceptron, is shown in an incremental setting to converge in a finite number of updates to solutions possessing any desirable fract

Victor Yodaiken

A method of using recursive functions to describe state change is applied to process switching in UNIX-like operating systems.

V. I. Tokar, H. Dreyssé

If a stochastic system during some periods of its evolution can be divided into non-interacting parts, the kinetics of each part can be simulated independently. We show that this can be used in the development of efficient Monte Carlo algorithms. As an illustrative example the simulation of irreversible growth of extended one dimensional islands is considere

Mehdi Hage-Hassan

We establish recurrences formulas of the order of the classical groups that allow us to find a generalization of Euler's angles for classical groups and the invariant measures of these groups. We find the generating function for the SU(2) subset of SU(3) basis in the Fock-Bargmann space and a new basis of SU(3). This new basis is eigenfunction of the squ

Rolf-Dieter Heuer, Annette Holtkamp, Salvatore Mele

Having always been at the forefront of information management and open access, High-Energy Physics (HEP) proves to be an ideal test-bed for innovations in scholarly communication including new information and communication technologies. Three selected topics of scholarly communication in High-Energy Physics are presented here: A new open access business mode

Antonio Ricco

We briefly report on some recent progress in the computation of B-brane superpotentials for Type II strings compactified on Calabi-Yau manifolds, obtained by using a parametrization of tubular neighborhoods of complex submanifolds, also known as local spaces. In particular, we propose a closed expression for the superpotential of a brane on a genus-g curve i

Vadim Shpitalnik, Yuval Gefen, Alessandro Romito

We propose and study a weak value (WV) protocol in the context of a solid state setup, specifically, an electronic Mach-Zehnder interferometer. This is the first specific proposal to measure both the real and imaginary part (i.e., complete tomography) of a WV. We also analyze the manifestation of many-body physics in the WV to be measured, including finite t

Wei Zhang, Ping Zhang, Suqing Duan, Xian-Geng Zhao

The low energy spectrum of a particle in planar honeycomb lattices is conical, which leads to the unusual electronic properties of graphene. In this letter we calculate the quasienergy spectra of a charged particle in honeycomb lattices driven by a strong AC field, which is of fundamental importance for its time-dependent dynamics. We find that depending on

H. Then, B. Thidé, J. T. Mendonça, T. D. Carozzi

Electromagnetic waves with an azimuthal phase shift are known to have a well defined orbital angular momentum. Different methods that allow for the detection of the angular momentum are proposed. For some, we discuss the required experimental setup and explore the range of applicability.

Esteban Andruchow, Gabriel Larotonda

In this article we follow the main idea of A. Connes for the construction of a metric in the state space of a C*-algebra. We focus in the reduced algebra of a discrete group $Γ$, and prove some equivalences and relations between two central objects of this category: the word-length growth (connected with the degree of the extension of $Γ$ when the group is a

R. Beattie, H. -P. Butzmann

Separately continuous bihomomorphisms on a product of convergence or topological groups occur with great frequency. Of course, in general, these need not be jointly continuous. In this paper, we exhibit some results of Banach-Steinhaus type and use these to derive joint continuity from separate continuity. The setting of convergence groups offers two advanta

Alin Ştefan

The discrete polymatroids and their base rings are studied recently in many papers (see \cite{HH}, \cite{HHV}, \cite{V1}, \cite{V2}). It is important to give conditions when the base ring associated to a transversal polymatroid is Gorenstein (see \cite{HH}). In \cite{SA} we introduced a class of such base rings. In this paper we note that an intersection of

P. Fonte, P. Martinengo, E. Nappi, R. Oliveira

We have recently developed an innovative detector of photons and charged particles: a GEM-like gaseous amplification structure with resistive electrodes instead of commonly used metallic ones. This novel detector combines the best property of GEMs- the capability to operate in a cascaded mode and in poorly quenched gases - and of RPC: the protection against

Mario Stipcevic

In this paper we present a novel construction of an active quenching circuit intended for single photon detection. For purpose of evaluation, we have combined this circuit with a standard avalanche photodiode C30902S to form a single photon detector. A series of measurements, presented here, show that this single photon detector has a dead time of less than

G. J. Conduit, P. H. Conlon, B. D. Simons

We explore the zero temperature phase behavior of a two-dimensional two-component atomic Fermi gas with population and mass imbalance in the regime of the BEC-BCS crossover. Working in the mean-field approximation, we show that the normal and homogeneous balanced superfluid phases are separated by an inhomogeneous superfluid phase of Fulde-Ferrel-Larkin-Ovch

Shunsaku Okada, Ryoko Nakamura, Manabu Ishida

We present {\it Chandra} HETG observations of SS Cygni in quiescence and outburst. The spectra are characterized by He-like and H-like Ka emission lines from O to Fe, as well as L-shell emission lines from Fe. In quiescence, the spectra are dominated by the H-like Ka lines, whereas in outburst the He-like lines are as intense as the H-like lines. In outburst

K. V. P. Latha, Dilip Angom, B. P. Das

We have developed an efficient tabulation scheme to evaluate $6j$ symbol for atomic calculations. The scheme is appropriate for coupled-cluster based calculations. In particular, for perturbed coupled-clusters calculations, which has another perturbation in addition to the residual Coulomb interaction. The scheme relies on the symmetry of the $6j$ symbol and

S. V. Ludkovsky

This article is devoted to the investigation of wrap groups of connected fiber bundles. CW-groups associated with wrap groups are studied.

J. Gava, C. Volpe

Core-collapse supernovae are powerful neutrino sources. The observation of a future (extra-)galactic supernova explosion or of the relic supernova neutrinos might provide important information on the supernova dynamics, on the supernova formation rate and on neutrino properties. One might learn more about unknown neutrino properties either from indirect effe

J. Villavicencio, I. Maldonado, R. Sánchez, E. Cota

Electronic transport in a triple quantum dot shuttle device in the presence of an ac field is analyzed within a fully quantum mechanical framework. A generalized density matrix formalism is used to describe the time evolution for electronic state occupations in a dissipative phonon bath. In the presence of an ac gate voltage, the electronic states are dresse

R. Citro, F. Romeo

A mesoscopic ring subject to the Rashba spin-orbit interaction and sequentially coupled to an interacting quantum dot, in the presence of Aharonov-Bohm flux, is proposed as a flux tunable tunneling diode. The analysis of the conductance by means of the nonequilibrium Green's function technique, shows an intrinsic bistability at varying the Aharonov-Bohm

Donatello Materassi, Giacomo Innocenti

The paper tackles the problem of deriving a topological structure among stock prices from high frequency historical values. Similar studies using low frequency data have already provided valuable insights. However, in those cases data need to be collected for a longer period and then they have to be detrended. An effective technique based on averaging a metr

Kenta Kiuchi, Masaru Shibata, Shijun Yoshida

We study the stability of neutron stars with toroidal magnetic fields by magnetohydrodynamic simulation in full general relativity under assumption of axial symmetry. Nonrotating and rigidly rotating neutron stars are prepared for a variety of magnetic field configuration. For modeling the neutron stars, the polytropic equation of state with the adiabatic in

Shaowei Chen

In this paper, we study the following semilinear Schrödinger equation with periodic coefficient: $$-\triangle u +V(x)u=f(x,u), u\in H^{1}(\mathbb{R}^{N}).$$ The functional corresponding to this equation possesses strongly indefinite structure. The nonlinear term $f(x,t)$ satisfies some superlinear growth conditions and need not be odd or increasing strictly

Bela Bollobas, Gabor Kun, Imre Leader

We consider the pursuit and evasion game on finite, connected, undirected graphs known as cops and robbers. Meyniel conjectured that for every graph on n vertices a rootish number of cops can win the game. We prove that this holds up to a log(n) factor for random graphs G(n,p) if p is not very small, and this is close to be tight unless the graph is very den

Adilson J. V. Brandao, Joao L. Martins

In this article we present a new recurrence formula for a finite sum involving the Fibonacci sequence. Furthermore, we state an algorithm to compute the sum of a power series related to Fibonacci series, without the use of term-by-term differentiation theorem

Sergei Urazhdin, Scott Button

We present systematic magnetoelectronic measurements of magnetic nanopillars with different structures of polarizing magnetic layers. The magnetic reversal at small magnetic field, the onset of magnetic dynamics at larger field, and the magnetoresistance exhibit a significant dependence on the type of the polarizing layer. We performed detailed quantitative

Valerio Lucarini

We perturb the SC, BCC, and FCC crystal structures with a spatial Gaussian noise whose adimensional strength is controlled by the parameter a, and analyze the topological and metrical properties of the resulting Voronoi Tessellations (VT). The topological properties of the VT of the SC and FCC crystals are unstable with respect to the introduction of noise,

Kazuki Hasebe

Supertwistor theory is geometrically constructed based on the SUSY Hopf map. We derive a new incidence relation for the geometrical supertwistor theory. The present supertwistor exhibits remarkable properties: Minkowski space need not be complexified to introduce spin degrees of freedom, and even number SUSY is {automatically} incorporated by the geometrical

Toshihiro Kasuga, David Jewitt

Apollo asteroid 1999 YC may share a dynamical association with the Phaethon-Geminid stream complex (Ohtsuka et al. 2008). Here, we present photometric observations taken to determine the physical properties of 1999 YC. The object shows a nearly neutral reflection spectrum, similar to but slightly redder than related objects 3200 Phaethon and 2005 UD. Assumin

Sudipto Guha, Kamesh Munagala

The celebrated multi-armed bandit problem in decision theory models the basic trade-off between exploration, or learning about the state of a system, and exploitation, or utilizing the system. In this paper we study the variant of the multi-armed bandit problem where the exploration phase involves costly experiments and occurs before the exploitation phase;

Shuai Dong, Rong Yu, Seiji Yunoki, J. -M. Liu

Most previous investigations have shown that the surface of a ferromagnetic material may have antiferromagnetic tendencies. However, experimentally the opposite effect has been recently observed: ferromagnetism appears in some nano-sized manganites with a composition such that the antiferromagnetic charge-ordered CE state is observed in the bulk. A possible

E. Catsigeras, A. Rovella, R. Budelli

We prove that a topologically generic network (an open and dense set of networks) of three or more inhibitory neurons have periodic behavior with a finite number of limit cycles that persist under small perturbations of the structure of the network. The network is modeled by the Poincare transformation which is piecewise continuous and locally contractive on

Nikolai Nadirashvili, Serge Vladuts

We study Hessian fully nonlinear uniformly elliptic equations and show that the second derivatives of viscosity solutions of those equations (in 12 or more dimensions) can blow up in an interior point of the domain. We prove that the optimal interior regularity of such solutions is no more than C^{1+ε}, showing the optimality of the known interior regularity

Alexei Vazquez

Data clustering, including problems such as finding network communities, can be put into a systematic framework by means of a Bayesian approach. The application of Bayesian approaches to real problems can be, however, quite challenging. In most cases the solution is explored via Monte Carlo sampling or variational methods. Here we work further on the applica

Matthew Ondrus, Emilie Wiesner

Whittaker modules have been well studied in the setting of complex semisimple Lie algebras. Their definition can easily be generalized to certain other Lie algebras with triangular decomposition, including the Virasoro algebra. We define Whittaker modules for the Virasoro algebra and obtain analogues to several results from the classical setting, including a

Spyros Sioutas, Dimitrios Sofotassios, Kostas Tsichlas, Dimitrios Sotiropoulos

The polygon retrieval problem on points is the problem of preprocessing a set of $n$ points on the plane, so that given a polygon query, the subset of points lying inside it can be reported efficiently. It is of great interest in areas such as Computer Graphics, CAD applications, Spatial Databases and GIS developing tasks. In this paper we study the problem

Jian-Wei Pan, Zeng-Bing Chen, Chao-Yang Lu, Harald Weinfurter

Multi-photon interference reveals strictly non-classical phenomena. Its applications range from fundamental tests of quantum mechanics to photonic quantum information processing, where a significant fraction of key experiments achieved so far comes from multi-photon state manipulation. We review the progress, both theoretical and experimental, of this rapidl

M. Anselmino, M. Boglione, U. D'Alesio, A. Kotzinian

We study the Sivers effect in the transverse single spin asymmetries (SSA) for pion and kaon production in semi-inclusive deep inelastic scattering (SIDIS) processes. We perform a fit of A^sin(phi_h-phi_S)_UT which, by including recent high statistics experimental data for pion and kaon production from HERMES and COMPASS Collaborations, allows a new determin

Laurent Schoeffel

Standard parton distribution functions contain neither information on the correlations between partons nor on their transverse motion, then a vital knowledge about the three dimensional structure of the nucleon is lost. Hard exclusive processes, in particular DVCS, are essential reactions to go beyond this standard picture. In the following, we examine the m

Vadim Gorin

We prove pairwise disjointness of representations T_{z,w} of the infinite-dimensional unitary group. These representations provide a natural generalization of the regular representation for the case of "big" group U(\infty). They were introduced and studied by G.Olshanski and A.Borodin. Disjointness of the representations can be reduced to disjointne

L. Canton, L. G. Levchuk

The formalism that describes radiative-capture reactions at low energies within an extended two-cluster potential model is presented. Construction of the operator of single-photon emission is based on a generalisation of the Siegert theorem with which the amplitude of the electromagnetic process is constructed in an explicitly gauge-independent way. While th

Yan Zhao, Pavel A. Belov, Yang Hao

Evanescent wave amplification is observed, for the first time to our knowledge, inside a half-wavelength-thick wire medium slab used for subwavelength imaging. The wire medium is analyzed using both a spatially dispersive finite-difference time-domain (FDTD) method and a full-wave commercial electromagnetic simulator CST Microwave Studio. In this work we dem

Marek Szydlowski, Pawel Tambor

Recent astronomical observations strongly indicate that the current Universe is undergoing an accelerated phase of expansion. The discovery of this fact was unexpected and resulted in the comeback of cosmological constant. The conception of standard cosmological model has its roots in this context. The paper relates to the methodological status of effective

Makoto Sakaguchi, Kentaroh Yoshida

We discuss (extended) super Schrodinger algebras obtained as subalgebras of the superconformal algebra psu(2,2|4). The Schrodinger algebra with two spatial dimensions can be embedded into so(4,2). In the superconformal case the embedded algebra may be enhanced to the so-called super Schrodinger algebra. In fact, we find an extended super Schrodinger subalgeb

Emil T. Akhmedov, Terry Pilling, Douglas Singleton

he quasi-classical method of deriving Hawking radiation is investigated. In order to recover the original Hawking temperature one must take into account a previously ignored contribution coming from the temporal part of the action. This contribution plus a contribution coming from the spatial part of the action gives the correct temperature.

Nobuo Yoshida

We consider a simple discrete-time Markov chain with values in $[0,\infty)^{Z^d}$. The Markov chain describes various interesting examples such as oriented percolation, directed polymers in random environment, time discretizations of binary contact path process and the voter model. We study the phase transition for the growth rate of the "total number of

Y. Ishida, T. Shimojima, K. Ishizaka, T. Kiss

We have performed a temperature-dependent angle-integrated laser photoemission study of iron oxypnictide superconductors LaFeAsO:F and LaFePO:F exhibiting critical transition temperatures (Tc's) of 26 K and 5 K, respectively. We find that high-Tc LaFeAsO:F exhibits a temperature-dependent pseudogap-like feature extending over ~0.1 eV about the Fermi leve

F. Kleefeld

A self-consistent strategy to complete the dynamical generation of Quark-Level-Linear-Sigma-Model-like Lagrangean theories beyond one loop as proposed in more detail in our manuscript arXiv:0802.1540 [hep-ph] is shortly outlined.

Vladimir Shpilrain, Alexander Ushakov

The conjugacy search problem in a group $G$ is the problem of recovering an $x \in G$ from given $g \in G$ and $h=x^{-1}gx$. The alleged computational hardness of this problem in some groups was used in several recently suggested public key exchange protocols, including the one due to Anshel, Anshel, and Goldfeld, and the one due to Ko, Lee et al. Sibert, De

Edward B. Jenkins

A disconcerting mismatch of thermal pressures for two media in contact with each other, (1) the warm, Circum-heliospheric Interstellar Medium (CHISM) and (2) the very hot material within a much larger region called the Local Bubble (LB), has troubled astronomers for over two decades. A possible resolution of this problem, at least in part, now seems possible

M. Revnivtsev, S. Sazonov, R. Krivonos, H. Ritter

We measure the spatial distribution and hard X-ray luminosity function of cataclysmic variables (CVs) using the INTEGRAL all-sky survey in the 17-60 keV energy band. The vast majority of the INTEGRAL detected CVs are intermediate polars with luminosities in the range 10^{32}-10^{34} erg/sec. The scale height of the Galactic disk population of CVs is found to

K. J. H. Law, H. Susanto, P. G. Kevrekidis

Solitons and necklaces in the first band-gap of a two-dimensional optically induced honeycomb defocusing photonic lattice are theoretically considered. It is shown that dipoles, soliton necklaces, and vortex necklaces exist and may possess regions of stable propagation through a photorefractive crystal. Most of the configurations disappear in bifurcations cl

J. D. Pandian, E. Momjian, P. F. Goldsmith

Distances to most star forming regions are determined using kinematics, through the assumption that the observed radial velocity arises from the motion of the source with respect to the Sun resulting from the differential rotation of Galaxy. The primary challenge associated with the application of this technique in the inner Galaxy is the kinematic distance

Misha Rudnev

In a recent paper \cite{Gl} A. Glibichuk proved that if $A,B$ are subsets of an arbitrary finite filed $\F_q$, such that $|A||B|>q$, then $16AB = \F_q$. We improve this to $10AB = \F_q.$

Alexey Alexandrov, Grigori Rozenblum

The recent theorem by D.Luecking about finite rank Bergman-Toeplitz operators is extended to weights being distributions with compact support and to the spaces of harmonic functions.

I. I. Guseinov, M. Erturk, E. Sahin

By the use of integer and noninteger n-Slater Type Orbitals in combined Hartree-Fock-Roothaan method, self consistent field calculations of orbital and lowest states energies have been performed for the isoelectronic series of open shell systems K [Ar]4s^0 3d^1 2(D) (Z=19-30) and Cr+ [Ar] 4s^0 3d^5 6(S) (Z=24-30). The results of calculations for the orbital

Kohtaro Tadaki

A real number αis called recursively enumerable if there exists a computable, increasing sequence of rational numbers which converges to α. The randomness of a recursively enumerable real αcan be characterized in various ways using each of the notions; program-size complexity, Martin-Löf test, Chaitin's Ωnumber, the domination and Ω-likeness of α, the un

M. V. Konnik, E. A. Manykin, S. N. Starikov

Methods of increasing linear optical dynamic range of commercial photocamera for optical-digital imaging systems are described. Use of such methods allows to use commercial photocameras for optical measurements. Experimental results are reported.

Leonid Verozub

In contrast to electrodynamics, Einstein's gravitation equations are not invariant with respect to a wide class of the mapping of field variables which leave equations of motion of test particles in a given coordinate system invariant. It seems obvious enough that just these mappings should play a role of gauge transformations of the variables in differe

C. Argiroffi, G. Peres, S. Orlando, F. Reale

The solar corona is a template to understand stellar activity. The Sun is a moderately active star, and its corona differs from active stars: active stellar coronae have a double-peaked EM(T) with the hot peak at 8-20 MK, while the non flaring solar corona has one peak at 1-2 MK. We study the average contribution of flares to the solar EM(T) to investigate i

Christof Teuscher, Natali Gulbahce, Thimo Rohlf

Independent of the technology, it is generally expected that future nanoscale devices will be built from vast numbers of densely arranged devices that exhibit high failure rates. Other than that, there is little consensus on what type of technology and computing architecture holds most promises to go far beyond today's top-down engineered silicon devices

Alex Buchel

The ratio of shear viscosity to entropy density in a strongly coupled CFT plasma can be computed using the AdS/CFT correspondence either from equilibrium correlation functions or from the Janik-Peschanski dual of the boost invariant plasma expansion. We point out that the previously found disagreement for eta/s at finite t' Hooft coupling is resolved onc

Tien-Cuong Dinh

We prove some properties of analytic multiplicative and sub-multiplicative cocycles. The results allow to construct natural invariant analytic sets associated to complex dynamical systems.

Rieuwert J. Blok Corneliu Hoffman

We obtain the symplectic group $\SP(V)$ as the universal completion of an amalgam of low rank subgroups akin to Levi components. We let $\SP(V)$ act flag-transitively on the geometry of maximal rank subspaces of $V$. We show that this geometry and its rank $\ge 3$ residues are simply connected with few exceptions. The main exceptional residue is described in

Xiongping Dai

In this paper, we study the structural stability of hyperbolic differential systems on Euclidean spaces using Liao theory.

Biao Li, Wenan Guo, Henk W. J. Blöte

A critical dilute O($n$) model on the kagome lattice is investigated analytically and numerically. We employ a number of exact equivalences which, in a few steps, link the critical O($n$) spin model on the kagome lattice to the exactly solvable critical $q$-state Potts model on the honeycomb lattice with $q=(n+1)^2$. The intermediate steps involve the random

Tom Wilde

Let F(x,y) be a function of two variables, and suppose y = f(x) satisfies F(x,y)=0 in some range. Then dy/dx = -Fx/Fy, where Fx and Fy denote the partial derivatives of F with respect to x and y. It is natural to seek a general expression for the higher derivatives d^ny/dx^n, in terms of partial derivatives of F, and such an expression was given in 1974 by L

Rui A. C. Ferreira, Delfim F. M. Torres

We establish some nonlinear integral inequalities for functions defined on a time scale. The results extend some previous Gronwall and Bihari type inequalities on time scales. Some examples of time scales for which our results can be applied are provided. An application to the qualitative analysis of a nonlinear dynamic equation is discussed.

Spyros Sioutas

In the particular case we have insertions/deletions at the tail of a given set S of $n$ one-dimensional elements, we present a simpler and more concrete algorithm than that presented in [Anderson, 2007] achieving the same (but also amortized) upper bound of $O(\sqrt{logd/loglogd})$ for finger searching queries, where $d$ is the number of sorted keys between

Syksy Rasanen

Observations of the expansion rate of the universe at late times disagree by a factor of 1.5-2 with the prediction of homogeneous and isotropic models based on ordinary matter and gravity. We discuss how the departure from linearly perturbed homogeneity and isotropy due to structure formation could explain this discrepancy. We evaluate the expansion rate in

D. Lutz, E. Sturm, L. J. Tacconi, E. Valiante

We present Spitzer rest-frame mid-infrared spectroscopy of twelve z~2 mm-bright type 1 QSOs, selected from unlensed and lensed QSO samples and covering a range of AGN optical luminosities L_5100=10^45 to 10^47 erg/s. On top of the AGN continuum, we detect PAH emission from luminous star formation in nine objects individually as well as in the composite spect

Kirill Krasnov, Yuri Shtanov

We describe how a certain simple modification of general relativity, in which the local cosmological constant is allowed to depend on the space-time curvature, predicts the existence of halos of modified gravity surrounding spherically-symmetric objects. We show that the gravitational mass of an object weighed together with its halo can be much larger than i

Sezen Sekmen

Unification of GUT-scale t-b-τYukawa couplings is a significant feature of simple SO(10) SUSY GUTs. Here we present the results of a search that used the Markov Chain Monte Carlo technique to investigate regions of Yukawa unification and WMAP-compatible dark matter relic density in SO(10)-like MSSM parameter spaces. We mention the possible LHC signatures of

Aurelien Galateau

We give a new lower bound for the essential minimum of subvarieties of abelian varieties with small codimension, under a conjecture about ordinary primes in abelian varieties. This lower bound is already known in the toric case since the work of Amoroso and David. It is the best expected, "up to an epsilon", in the degree of the subvariety.

Lev Sakhnovich

We consider the Knizhnik-Zamolodchikov system of linear differential equations. The coefficients of this system are rational functions. We prove that under some conditions the solution of KZ system is rational too. We give the method of constructing the corresponding rational solution. We deduce the asymptotic formulas for the solution of KZ system when $ρ$

S. L. Narasimhan, A. Baumgaertner

We have performed a detailed Monte Carlo study of a diffusionless $(1+1)$-dimensional solid-on-solid model of particle deposition and evaporation that not only tunes the roughness of an equilibrium surface but also demonstrates the need for more than two exponents to characterize it. The tunable parameter, denoted by $μ$, in this model is the dimensionless s

Arnab Sen, Fa Wang, Kedar Damle

Antiferromagnetically coupled moments on the frustrated triangular lattice typically order in a coplanar state at low temperature. Here, we demonstrate that the presence of not-very-large easy axis single ion anisotropy leads to an interesting orientationally ordered collinear state in triangular lattice antiferromagnets with moments $S \ge 3/2$. This ordere

E. Sonbas, A. S. Moskvitin, T. A. Fatkhullin, V. V. Sokolov

In BTA spectra of the supernova SN2006aj, identified with the X-ray flash (XRF) and gamma-ray burst XRF/GRB060218/SN2006aj, we detected details interpreted as hydrogen lines, which is a sign of stellar-wind envelope around a massive progenitor star of the gamma-ray burst. Results of modeling two early spectra obtained with the BTA in 2.55 and 3.55 days after

Barbu Berceanu, Zaffar Iqbal

In this paper we study the growth rates of Artin monoids and we show that 4 is a universal upper bound. We also show that the generating functions of the associated right-angled Artin monoids are given by families of Chebyshev polynomials. Applications to Artin groups and positive braids are given.

W. Gieren, G. Pietrzynski, O. Szewczyk, F. Bresolin

We have obtained deep images in the near-infrared J and K filters for several fields in the Local Group galaxy WLM. We report intensity mean magnitudes for 31 Cepheids located in these fields which we previously discovered in a wide-field optical imaging survey of WLM. The data define tight period-luminosity relations in both near-infrared bands which we use

David Gérard-Varet, Matthieu Hillairet

We investigate the evolution of rigid bodies in a viscous incompressible fluid. The flow is governed by the 2D Navier-Stokes equations, set in a bounded domain with Dirichlet boundary conditions. The boundaries of the solids and the domain have Hölder regularity $C^{1, α}$, $0 < α\le 1$. First, we show the existence and uniqueness of strong solutions up to c

B. Pradhan, Pankaj Agrawal, A. K. Pati

We consider W-states and generalized W-states for $n$-qubit systems. We obtain conditions to use these states as quantum resources to teleport unknown states. Only a limited class of multi-qubit states can be teleported. For $one$-qubit states, we use protocols which are simple extensions of the conventional teleportation protocol. We also show that these re

S. P. Baranov, A. V. Lipatov, N. P. Zotov

In the framework of the kt-factorization approach, we study the production of prompt photons associated with heavy (charm and beauty) quarks in hadron-hadron collisions at high energies. Our consideration is based on the amplitude for the production of a single photon associated with a quark pair in the fusion of two off-shell gluons. The total and different

A. Nakanishi, T. Ishikawa, H. Nagara, K. Kusakabe

By means of first-principles calculations, we studied stable lattice structures and estimated superconducting transition temperature of CaSi$_2$ at high pressure. Our simulation showed stability of the AlB$_2$ structure in a pressure range above 17 GPa. In this structure, doubly degenerated optical phonon modes, in which the neighboring silicon atoms oscilla

Pierre Gosselin, Alain Berard, Herve Mohrbach

It has been recently found that the equations of motion of several semiclassical systems must take into account anomalous velocity terms arising from Berry phase contributions. Those terms are for instance responsible for the spin Hall effect in semiconductors or the gravitational birefringence of photons propagating in a static gravitational field. Intensiv

Ilias Diakonikolas, Mihalis Yannakakis

We investigate the problem of computing a minimum set of solutions that approximates within a specified accuracy $ε$ the Pareto curve of a multiobjective optimization problem. We show that for a broad class of bi-objective problems (containing many important widely studied problems such as shortest paths, spanning tree, and many others), we can compute in po

Diana Vaman, York-Peng Yao

Recursion relations are succinctly obtained for $(++... +)$ and $(-++... +)$ amplitudes in the context of the space-cone gauge in QCD. We rely on the helicity symmetry of the problems to dictate our choices of reference twistors and the momentum shifts to complexify the amplitudes. Of great importance is the power of gauge Lorentz invariance, which is enough

R. L. Oldershaw

For more than a half century cosmologists have been guided by the assumption that matter is distributed homogeneously on sufficiently large scales. On the other hand, observations have consistently yielded evidence for inhomogeneity in the distribution of matter right up to the limits of most surveys. The apparent paradox can be understood in terms of the ro

Cheongho Han

We investigate the characteristic of microlensing signals of Earth-like moons orbiting ice-giant planets. From this, we find that non-negligible satellite signals occur when the planet-moon separation is similar to or greater than the Einstein radius of the planet. We find that the satellite signal does not diminish with the increase of the planet-moon separ

Hossein Bagheri, Abolfazl S. Motahari, Amir K. Khandani

We consider a diamond-shaped dual-hop communication system consisting a source, two parallel half-duplex relays and a destination. In a single antenna configuration, it has been previously shown that a two-phase node-scheduling algorithm, along with the decode and forward strategy can achieve the capacity of the diamond channel for a certain symmetric channe

Jinyuan Du, Zhihua Du

In this paper, we study the theory of orthogonal trigonometric polynomials (OTP). We obtain asymptotics of OTP with positive and analytic weight functions by Riemann-Hilbert approach and find they have relations with orthogonal polynomials on the unit circle (OPUC). By the relations and the theory of OPUC, we also get four-terms recurrent formulae, Christoff

Jun Furuya, Wenguang Zhai

Let $Δ^{(k)}(x)$ denote the error term of the $k$-free divisor problem for $k\geq 2$. In this paper we establish an asymptotic formula of the integral $\int_1^T|Δ^{(k)}(x)|^2dx$ for each $k\geq 4.$

H. Susanto, K. Law, P. G. Kevrekidis, L. Tang

Dipole and quadrupole solitons in a two-dimensional optically induced defocus- ing photonic lattice are theoretically predicted and experimentally observed. It is shown that in-phase nearest-neighbor dipole and out-of-phase next-nearest-neighbor dipoles exist and can be stable in the intermediate intensity regime. The other types of dipoles are always unstab

Georg H. Hoffstaetter, Yang Hao Lau

Energy Recovery Linacs provide high-energy beams, but decelerate those beams before dumping them, so that their energy is available for the acceleration of new particles. During this deceleration, any relative energy spread that is created at high energy is amplified by the ratio between high energy and dump energy. Therefore, Energy Recovery Linacs are sens

F. T. Farrell, P. Ontaneda

We study the moduli space of negatively curved metrics of a hyperbolic manifold.

V. V. Nesvizhevsky, E. V. Lychagin, A. Yu. Muzychka, A. V. Strelkov

We study possibility of efficient reflection of very cold neutrons (VCN) from powders of nanoparticles. In particular, we measured the scattering of VCN at a powder of diamond nanoparticles as a function of powder sample thickness, neutron velocity and scattering angle. We observed extremely intense scattering of VCN even off thin powder samples. This agrees