October 2009 arXiv papers — page 14

A. Monin, M. B. Voloshin

The rate of $e^+e^-$ pair creation by external electric field in the presence of an incident photon beam is calculated for the photon energy far below the threshold, $ω\ll m$, and the field strength small as compared to the critical one, $e E \ll m^2$. We find the pair production rate using a recently developed method based on calculation of the process in a

Giovanni Catino, Carlo Mantegazza

We compute the evolution equation of the Weyl tensor under the Ricci flow of a Riemannian manifold and we discuss some consequences for the classification of locally conformally flat Ricci solitons.

Jonathan I. Hall, Hung Ngoc Nguyen

We study the odd-characteristic structure of permutation modules for the rank 3 natural actions of $O_{2n}^{\pm}(2)$ ($n\geq3$) and $U_{m}(2)$ ($m\geq4$) on nonsingular points of their standard modules.

Linda Gruendken, Laura Hall-Seelig, Bo-Hae Im, Ekin Ozman

Let $k$ be an algebraically closed field of characteristic $p>0$. Let $G$ be $Z/\ell Z$ semi-direct product $Z/pZ$ where $\ell$ is a prime distinct from $p$. In this paper, we study Galois covers $ψ:Z \to P^1_k$ ramified only over $\infty$ with Galois group $G$. We find the minimal genus of a curve $Z$ that admits such a cover and show that it depends only o

Sohyun Park, R. P. Woodard

We study a conjecture involving the invariant volume of the past light-cone from an arbitrary observation point back to a fixed initial value surface. The conjecture is that a 4th order differential operator which occurs in the theory of conformal anomalies gives $8π$ when acted upon the invariant volume of the past light-cone. We show that an extended versi

Vladimir Shevelev

Using the Rowland idea, we find two infinite sets of generators of primes. We also pose some conjectures concerning twin primes.

Abraham I. Harte

Deriving the motion of a compact mass or charge can be complicated by the presence of large self-fields. Simplifications are known to arise when these fields are split into two parts in the so-called Detweiler-Whiting decomposition. One component satisfies vacuum field equations, while the other does not. The force and torque exerted by the (often ignored) i

Philip Tynan

Let X be some Riemann surface, and let omega be a meromorphic quadratic differential form on X, that is, omega can be written in local coordinates as f(z) dz^2, for some meromorphic function f. We say that a curve gamma is part of a horizontal leaf of omega if for each t in I, we have that f(gamma(t)) (gamma'(t))^2 is real and positive. The differential

Belle Collaboration, K. Nishimura, T. E. Browder, I. Adachi

We report a first measurement of inclusive B -> X_s eta decays, where X_s is a charmless state with unit strangeness. The measurement is based on a pseudo-inclusive reconstruction technique and uses a sample of 657 x 10^6 BB-bar pairs accumulated with the Belle detector at the KEKB e^+e^- collider. For M_{X_s} < 2.6 GeV/c^2, we measure a branching fraction o

Gholamreza Shayeganrad, Leila Mashhadi, Davood Momeni

This study presents theoretical investigation of the effects of particle and molecular extinction in horizontal remote sensing near the ground for several visibilities at UV wavelengths by neglecting the spatial inhomogeneity of aerosol in the atmosphere and taking into account the dependence of refracting on air temperature and pressure. Due to weak attenua

Ikkei Hotta

Ruscheweyh extended the work of Becker and Ahlfors on sufficient conditions for a normalized analytic function on the unit disk to be univalent there. In this paper we refine the result to a quasiconformal extension criterion with the help of Becker&#39;s method. As an application, a positive answer is given to an open problem proposed by Ruscheweyh.

Roberto Giacobazzi, Francesco Ranzato

In abstract interpretation-based static analysis, approximation is encoded by abstract domains. They provide systematic guidelines for designing abstract semantic functions that approximate some concrete system behaviors under analysis. It may happen that an abstract domain contains redundant information for the specific purpose of approximating a given conc

G. Oelsner, S. H. W. van der Ploeg, P. Macha, U. Hübner

We study a flux qubit in a coplanar waveguide resonator by measuring transmission through the system. In our system with the flux qubit decoupled galvanically from the resonator, the intermediate coupling regime is achieved. In this regime dispersive readout is possible with weak backaction on the qubit. The detailed theoretical analysis and simulations give

Bernd A. Berg

Gauge invariance is extended to allow to allow for a U(1)-SU(2) mixing term, which can cause a SU(2) deconfining transition.

An Zeng, Yanqing Hu, Zengru Di

The loop structure plays an important role in many aspects of complex networks and attracts much attention. Among the previous works, Bianconi et al find that real networks often have fewer short loops as compared to random models. In this paper, we focus on the uneven location of loops which makes some parts of the network rich while some other parts sparse

I. Schmelzer

Schulz claims to have constructed an actively local stochastic theory which violates Bell&#39;s inequality. This is false.

J. F. Geurdes

A classical probabilistic explanation for Hardy&#39;s quantum paradox is demonstrated.

C. H. Eab, S. C. Lim

Fractional generalized Langevin equation with external force is used to model single-file diffusion. It is found that for external force that varies with power law the solution for such a fractional Langevin equation gives the correct short and long time behavior for the mean square displacement of single-file diffusion when appropriate choice of parameters

V. G. Kogan, C. Martin, R. Prozorov

Response to Comment by A. Bussmann-Holder (arXiv:0909.3603)

Stan Lai

The presence of tau leptons in the final state is an important signature in searches for physics beyond the Standard Model. Hadronically decaying tau leptons can be reconstructed over a wide kinematic range at ATLAS. The reconstruction algorithm for hadronically decaying tau leptons and the performance of tau lepton identification is described. A review of p

Rashid Rezaei, Francesco G. Russo

The line of investigation of the present paper goes back to a classical work of W. H. Gustafson of the 1973, in which it is described the probability that two randomly chosen group elements commute. In the same work, he gave some bounds for this kind of probability, providing information on the group structure. We have recently obtained some generalizations

Shoham Shamir

Let R be a ring and let T be a hereditary torsion class of R-modules. The inclusion of the localizing subcategory generated by T into the derived category of R has a right adjoint, which is a colocalization. Benson has recently shown how to compute this right sdjoint when R is the group ring of a finite group over a prime field and T is the hereditary torsio

Gerrit E. W. Bauer, Stefan Bretzel, Arne Brataas, Yaroslav Tserkovnyak

We present the linear response matrix for a sliding domain wall in a rotatable magnetic nanowire, which is driven out of equilibrium by temperature and voltage bias, mechanical torque, and magnetic field. An expression for heat-current induced domain wall motion is derived. Application of Onsager&#39;s reciprocity relation leads to a unified description of t

Johannnes-Geert Hagmann, Naoko Nakagawa, Michel Peyrard

Recent studies attracted the attention on the inherent structure landscape (ISL) approach as a reduced description of proteins allowing to map their full thermodynamic properties. However, the analysis has been so far limited to a single topology of a two-state folding protein, and the simplifying assumptions of the method have not been examined. In this wor

Sang-hyun Kim, Henry Wilton

A longstanding question of Gromov asks whether every one-ended word-hyperbolic group contains a subgroup isomorphic to the fundamental group of a closed hyperbolic surface. An infinite family of word-hyperbolic groups can be obtained by taking doubles of free groups amalgamated along words that are not proper powers. We define a set of polygonal words in a f

Rong-Gen Cai, Yan Liu, Ya-Wen Sun

We calculate the shear viscosity of strongly coupled field theories dual to Gauss-Bonnet gravity at zero temperature with nonzero chemical potential. We find that the ratio of the shear viscosity over the entropy density is $1/4π$, which is in accordance with the zero temperature limit of the ratio at nonzero temperatures. We also calculate the DC conductivi

Sergei A. Zibrov, Irina Novikova, David F. Phillips, Ronald L. Walsworth

We present a joint theoretical and experimental characterization of the coherent population trapping (CPT) resonance excited on the D1 line of 87Rb atoms by bichromatic linearly polarized laser light. We observe high-contrast transmission resonances (up to 25%), which makes this excitation scheme promising for miniature all-optical atomic clock applications.

Jihoon Park, Przemysław Pawełczak, Danijela Čabrić

We present an analytical framework to assess the link layer throughput of multichannel Opportunistic Spectrum Access (OSA) ad hoc networks. Specifically, we focus on analyzing various combinations of collaborative spectrum sensing and Medium Access Control (MAC) protocol abstractions. We decompose collaborative spectrum sensing into layers, parametrize each

Re-Bing Wu, Michael A. Hsieh, Herschel Rabitz

This paper discusses the important role of controllability played on the complexity of optimizing quantum mechanical control systems. The study is based on a topology analysis of the corresponding quantum control landscape, which is referred to as the optimization objective as a functional of control fields. We find that the degree of controllability is clos

Rafael Ferraro, Franco Fiorini

In the context of Born-Infeld \emph{determinantal} gravity formulated in a n-dimensional spacetime with absolute parallelism, we found an exact 3-dimensional \emph{vacuum} circular symmetric solution without cosmological constant consisting in a rotating spacetime with non singular behavior. The space behaves at infinity as the conical geometry typical of 3-

Svjetlan Feretic

In most of today&#39;s exactly solved classes of polyominoes, either all members are convex (in some way), or all members are directed, or both. If the class is neither convex nor directed, the exact solution uses to be elusive. This paper is focused on polyominoes with hexagonal cells. Concretely, we deal with polyominoes whose columns can have either one o

M. J. Keith, S. Johnston, M. Kramer, P. Weltevrede

We present polarisation observations of five pulsars whose profiles exhibit two distinct emission regions separated by close to 180 degrees of longitude. We fitted the position angle of the linear polarisation using the rotating vector model and convincingly show that all the pulsars have the angle between their magnetic and rotation axes close to 90 degrees

Matthew B. Day

We extend each higher Johnson homomorphism to a crossed homomorphism from the automorphism group of a finite-rank free group to a finite-rank abelian group. We also extend each Morita homomorphism to a crossed homomorphism from the mapping class group of once-bounded surface to a finite-rank abelian group. This improves on the author&#39;s previous results [

R. R. Cuzinatto, P. J. Pompeia, M. de Montigny, F. C. Khanna

We examine the weak-field approximation of locally Galilean invariant gravitational theories with general covariance in a $(4+1)$-dimensional Galilean framework. The additional degrees of freedom allow us to obtain Poisson, diffusion, and Schrödinger equations for the fluctuation field. An advantage of this approach over the usual $(3+1)$-dimensional General

Cheng Zhao, Lei Jiang, Xunxu Liu, W. M. Liu

We construct a fully self-consistent Hartree-Fock-Bogoliubov theory that describes a spinless Fermi gas with long-range interaction. We apply this theory to a system of uniform dipolar fermionic polar molecules, which has attracted much attention recently, due to rapid experimental progress in achieving such systems. By calculating the anisotropic superfluid

Ruy Fabila-Monroy, David Flores-Peñaloza, Clemens Huemer, Ferran Hurtado

For a graph $G$ and integer $k\geq1$, we define the token graph $F_k(G)$ to be the graph with vertex set all $k$-subsets of $V(G)$, where two vertices are adjacent in $F_k(G)$ whenever their symmetric difference is a pair of adjacent vertices in $G$. Thus vertices of $F_k(G)$ correspond to configurations of $k$ indistinguishable tokens placed at distinct ver

J. M. Diederik Kruijssen, Steffen Mieske

The observed mass-to-light (M/L) ratios of globular clusters (GCs) are on average ~20% lower than expected from Simple Stellar Population (SSP) models, which only account for the effects of stellar evolution. We study the M/L ratio evolution of a sample of 24 Galactic GCs using parameterised cluster models. The dynamical evolution of GCs is included by accou

W. J. Munro, K. Nemoto, G. J. Milburn

We investigate a doubly resonant optical cavity containing a Kerr nonlinear medium that couples two modes by a cross phase modulation. One of these modes is driven by a single photon pulsed field, and the other mode is driven by a coherent state. We find an intrinsic phase noise mechanism for the cross phase shift on the coherent beam which can be attributed

Rustam Sadykov

Characteristic classes of oriented vector bundles can be identified with cohomology classes of the disjoint union of classifying spaces BSO_n of special orthogonal groups SO_n with n=0,1,... A characteristic class is stable if it extends to a cohomology class of a homotopy colimit BSO of classifying spaces BSO_n. Similarly, characteristic classes of smooth o

Azza Harbaoui, Malek Ghenima, Sahbi Sidhom

Information retrieval (IR) is a user approach to obtain relevant information which meets needs with the help of a IR system (IRS). However, the IRS shows certain differences between user relevance and system relevance. These gaps are essentially related to the imperfection of the indexing process (as approach related to the IR), to problems related to the mi

Pierre-André Zitt

We prove some results about the super Poincaré inequality (SPI) and its relation to the spectrum of an operator: we show that it can be alternatively written with Orlicz norms instead of L1 norms, and we use this to give an alternative proof that a bound on the bottom of the essential spectrum implies a SPI. Finally, we apply these ideas to give a spectral p

Sandor Varro

In the present paper an example of entanglement between two different kinds of interacting particles, photons and electrons is analysed. The initial-value problem of the Schroedinger equation is solved non-perturbatively for the system of a free electron interacting with a quantized mode of the electromagnetic radiation. Wave packets of the dressed states so

Jens Zumbrägel

A ringoid is a set with two binary operations that are linked by the distributive laws. We study special classes of ringoids that are congruence-simple or ideal-simple. In particular, we examine generalised parasemifields and non-associative semirings.

Frank Himstedt, Hung Ngoc Nguyen, Pham Huu Tiep

We prove that the restriction of any nontrivial representation of the Ree groups $^2F_{4}(q), q=2^{2n+1}\geq8$ in odd characteristic to any proper subgroup is reducible. We also determine all triples $(K, V, H)$ such that $K \in \{^2F_4(2), ^2F_4(2)&#39;\}$, $H$ is a proper subgroup of $K$, and $V$ is a representation of $K$ in odd characteristic restricting

Kelley Rivoire, Ziliang Lin, Fariba Hatami, W. Ted Masselink

We demonstrate second harmonic generation in photonic crystal nanocavities fabricated in the semiconductor gallium phosphide. We observe second harmonic radiation at 750 nm with input powers of only nanowatts coupled to the cavity and conversion efficiency $P_{\rm out}/P_{\rm in, coupled}^2 = 430%/{\rm W}$. The large electronic band gap of GaP minimizes abso

L. Kolokolova, H. Kimura

The most successful model of comet dust presents comet particles as aggregates of submicron grains. It qualitatively explains the spectral and angular change in the comet brightness and polarization and is consistent with the thermal infrared data and composition of the comet dust obtained {\it in situ} for comet 1P/Halley. However, it experiences some diffi

Albert De Roeck, Rolf Ent

For the session on future facilities at DIS09 discussions were organized on DIS related measurements that can be expected in the near and medium - or perhaps far - future, including plans from JLab, CERN and FNAL fixed target experiments, possible measurements and detector upgrades at RHIC, as well as the plans for possible future electron proton/ion collide

Vladislav V. Goldberg, Valentin V. Lychagin

The authors found necessary and sufficient conditions for Samuelson&#39;s web to be of maximum rank.

A. J. Buchmann

We show that the non-spherical charge distribution of the proton manifests itself in hydrogen hyperfine splitting as an increase (in absolute value) of the proton Zemach radius and polarization contributions.

Ingrid Beltita, Daniel Beltita

We present some recent results on smooth vectors for unitary irreducible representations of nilpotent Lie groups. Applications to the Weyl-Pedersen calculus of pseudo-differential operators with symbols on the coadjoint orbits are also discussed.

O. Scholten, S. Buitink, J. Bacelar, R. Braun

Particle cascades initiated by ultra-high energy (UHE) neutrinos in the lunar regolith will emit an electromagnetic pulse with a time duration of the order of nano seconds through a process known as the Askaryan effect. It has been shown that in an observing window around 150 MHz there is a maximum chance for detecting this radiation with radio telescopes co

Yonah Cherniavsky

We present the poset of Borel congruence classes of anti-symmetric matrices ordered by containment of closures. We show that there exists a bijection between the set of these classes and the set of involutions of the symmetric group. We give two formulas for the rank function of this poset.

Federico Ramponi, Debasish Chatterjee, Sean Summers, John Lygeros

Probabilistic Computation Tree Logic (PCTL) is a well-known modal logic which has become a standard for expressing temporal properties of finite-state Markov chains in the context of automated model checking. In this paper, we give a definition of PCTL for noncountable-space Markov chains, and we show that there is a substantial affinity between certain of i

Julio C. Fabris, Deborah F. Jardim

The dark energy component of the cosmic budget is represented by a self-interacting scalar field. The violation of the null energy condition is allowed. Hence, such component can also represent a phantom fluid. The model is tested using supernova type Ia and matter power spectrum data. The supernova test leads to preferred values for configurations represent

Timothy C. Beers

Although originally conceived as primarily an extragalactic survey, the Sloan Digital Sky Survey (SDSS-I), and its extensions SDSS-II and SDSS-III, continue to have a major impact on our understanding of the formation and evolution of our host galaxy, the Milky Way. The sub-survey SEGUE: Sloan Extension for Galactic Exploration and Understanding, executed as

E. Caffau, H. -G. Ludwig, M. Steffen

The solar abundances have undergone a major downward revision in the last decade, reputedly as a result of employing 3D hydrodynamical simulations to model the inhomogeneous structure of the solar photosphere. The very low oxygen abundance advocated by Asplund et al. (2004), A(O)=8.66, together with the downward revision of the carbon and nitrogen abundances

I. F. Ginzburg

Some features of old results in the total summation of all logarithmic contributions of all diagrams in Yukawa theory are presented. We discuss some lessons from this picture for the description of Pomeron, odderon, etc. in QCD.

Timothy C. Beers, Deokkeun An, Jennifer A. Johnson, Marc H. Pinsonneault

We describe the methodology required for estimation of photometric estimates of metallicity based on the SDSS gri passbands, which can be used to probe the properties of main-sequence stars beyond ~ 10 kpc, complementing studies of nearby stars from more metallicity-sensitive color indices that involve the u passband. As a first application of this approach,

P. Bonifacio, E. Caffau, H. -G. Ludwig

We make use of three dimensional hydrodynamical simulations to investigate the effects of granulation on the Cu I lines of Mult. 1 in the near UV, at 324.7 nm and 327.3 nm. These lines remain strong even at very low metallicity and provide the opportunity to study the chemical evolution of Cu in the metal-poor populations. We find very strong granulation eff

V. G. Kogan

The puzzling features of the slopes of the upper critical field at the critical temperature $T_c$, $H^\prime_{c2}(T_c)\propto T_c$, and of the specific heat jump $ΔC\propto T_c^3$ of iron-pnictides are interpreted as caused by a strong pair-breaking.

Kazunari Iwasaki, Toru Tsuribe

In this paper, the stability of a dynamically condensing radiative gas layer is investigated by linear analysis. Our own time-dependent, self-similar solutions describing a dynamical condensing radiative gas layer are used as an unperturbed state. We consider perturbations that are both perpendicular and parallel to the direction of condensation. The transve

M. C. Wyatt, M. Booth, M. J. Payne, L. J. Churcher

Models for the steady state collisional evolution of low eccentricity planetesimal belts identify debris disks with hot dust at 1AU, like eta Corvi and HD69830, as anomalous since collisional processing should have removed most of the planetesimal mass over their >1 Gyr lifetimes. This paper looks at the effect of large planetesimal eccentricities (e>>0.3) o

István Prause, Stanislav Smirnov

We give improved bounds for the distortion of the Hausdorff dimension under quasisymmetric maps in terms of the dilatation of their quasiconformal extension. The sharpness of the estimates remains an open question and is shown to be closely related to the fine structure of harmonic measure.

Y. G. Shi, Y. F. Guo, S. Yu, M. Arai

Newly synthesized perovskite NaOsO3 shows Curie-Weiss metallic nature at high temperature and suddenly goes into an antiferromagnetically insulating state at 410 K on cooling. Electronic specific heat at the low temperature limit is absent, indicating that the band gap fully opens. In situ observation in electron microscopy undetected any lattice anomalies i

Guy Barles, Francesca Da Lio

In this article, we prove the local $C^{0,α}$ regularity and provide $C^{0,α}$ estimates for viscosity solutions of fully nonlinear, possibly degenerate, elliptic equations associated to linear or nonlinear Neumann type boundary conditions. The interest of these results comes from the fact that they are indeed regularity results (and not only a priori estima

Guy Barles, Francesca Da Lio, Pierre-Louis Lions, Panagiotis E. Souganidis

We study periodic homogenization problems for second-order pde in half-space type domains with Neumann boundary conditions. In particular, we are interested in &#34;singular problems&#34; for which it is necessary to determine both the homogenized equation and boundary conditions. We provide new results for fully nonlinear equations and boundary conditions.

Wolfgang Krieger, Kengo Matsumoto

We introduce a class of subshifts under the name of &#34;standard one-counter shifts&#34;. The standard one-counter shifts are the Markov coded systems of certain Markov codes that belong to the family of one-counter languages. We study topological conjugacy and flow equivalence of standard one-counter shifts. To subshifts there are associated C*-algebras by

Patrick M. Koch, Michael Kesteven, Yu-Yen Chang, Yau-De Huang

The Array for Microwave Background Anisotropy (AMiBA) is a radio interferometer for research in cosmology, currently operating 7 0.6m diameter antennas co-mounted on a 6m diameter platform driven by a hexapod mount. AMiBA is currently the largest hexapod telescope. We briefly summarize the hexapod operation with the current pointing error model. We then focu

Herbert Abels, Antonios Manoussos

In this note we give an example of a one-dimensional manifold with two connected components and a complete metric whose group of isometries has an orbit which is not closed. This answers a question of S. Gao and A. S. Kechris.

Radoslaw Szmytkowski

In a series of recent works, we have provided a number of explicit expressions for the derivative of the associated Legendre function of the first kind with respect to its degree, $[\partial P_ν^{m}(z)/\partialν]_{ν=n}$, with $m,n\in\mathbb{N}$. In this communication, we use some of those expressions to obtain several, we believe new, explicit formulas for t

Ofer Lahav, Angeliki Kiakotou, Filipe B. Abdalla, Chris Blake

We study the prospects for detecting neutrino masses from the galaxy angular power spectrum in photometric redshift shells of the Dark Energy Survey (DES) over a volume of 20 (Gpc/h)^3 combined with the Cosmic Microwave Background (CMB) angular fluctuations expected to be measured from the Planck satellite. We find that for a Lambda-CDM concordance model wit

Jyotishman Bhowmick, Debashish Goswami

By considering spectral triples on $S^{2}_{μ, c}$ ($c>0$) constructed by Chakraborty and Pal (\cite{chak_pal}), we show that in general the quantum group of volume and orientation preserving isometries (in the sense of \cite{goswami2}) for a spectral triple of compact type may not have a $C^*$-action, and moreover, it can fail to be a matrix quantum group. I

Qiong Ma, Zhi-Rong Lin, Tao Tu, Guang-Can Guo

We propose a new method to use gapped graphene as barrier to confine electrons in gapless graphene and form a good quantum dot, which can be realized on an oxygen-terminated $SiO_{2}$ substrate partly H-passivated. In particular, we use ferromagnetic insulators deposited on top of barrier which give rise to a spin related energy spectrum and transport proper

Lucas Guillemot

The Fermi observatory was launched on June 11, 2008. It hosts the \emph{Large Area Telescope} (LAT), sensitive to $γ$-ray photons from 20 MeV to over 300 GeV. When the LAT began its activity, nine young and energetic pulsars were known in $γ$ rays. At least several tens of pulsar detections by the LAT were predicted before launch. The LAT also allowed the st

N. N. Achasov, G. N. Shestakov

After a short review of the production mechanisms of the light scalars which reveal their nature and indicate their quark structure, we suggest to study the mixing of the isovector a^0_0(980) with the isoscalar f_0(980) in spin effects.

Hakima Bessaih, Franco Flandoli, Edriss S. Titi

Recently, it has been proposed that the Navier-Stokes equations and a relevant linear advection model have the same long-time statistical properties, in particular, they have the same scaling exponents of their structure functions. This assertion has been investigate rigorously in the context of certain nonlinear deterministic phenomenological shell model, t

M. Petrovic, M. Belic, C. Denz, Yu. Kivshar

Physics of counterpropagating optical beams and spatial optical solitons is reviewed, including the formation of stationary states and spatiotemporal instabilities. First, several models describing the evolution and interactions between optical beams and spatial solitons are discussed, that propagate in opposite directions in nonlinear media. It is shown tha

Noga Alon, Felix Fischer, Ariel D. Procaccia, Moshe Tennenholtz

We consider directed graphs over a set of n agents, where an edge (i,j) is taken to mean that agent i supports or trusts agent j. Given such a graph and an integer k\leq n, we wish to select a subset of k agents that maximizes the sum of indegrees, i.e., a subset of k most popular or most trusted agents. At the same time we assume that each individual agent

Scott Aaronson

The relationship between BQP and PH has been an open problem since the earliest days of quantum computing. We present evidence that quantum computers can solve problems outside the entire polynomial hierarchy, by relating this question to topics in circuit complexity, pseudorandomness, and Fourier analysis. First, we show that there exists an oracle relation

Liang Cao, Li-Zhi Fang

We develop an algorithm of separating the $E$ and $B$ modes of the CMB polarization from the noisy and discretized maps of Stokes parameter $Q$ and $U$ in a finite area. A key step of the algorithm is to take a wavelet-Galerkin discretization of the differential relation between the $E$, $B$ and $Q$, $U$ fields. This discretization allows derivative operator

Andrew Douglas, K. A. Muttalib

We obtain an analytic expression for the full distribution of conductance for a strongly disordered three dimensional conductor within a perturbative approach based on the transfer-matrix formulation. Our results confirm numerical evidence that the log-normal limit of the distribution is not reached even in the deeply insulating regime. We show that the vari

Khireddine Nouicer, Youssef Sabri

In this paper we study the effect of spacetime noncommutativity in the 5-dimensional Randall-Sundrum brane worlds on the Casimir force acting on a pair of parallel plates. We show that the presence of a noncommutative scale length affects the nature of the Casimir force for small plate separation. Using accurate experimental bounds for the Casimir force in p

Yifei Wu

We study the Cauchy problem of the Schrödinger-Korteweg-de Vries system. First, we establish the local well-posedness results, which improve the results of Corcho, Linares (2007). Moreover, we obtain some ill-posedness results, which show that they are sharp in some well-posedness thresholds. Particularly, we obtain the local well-posedness for the initial d

Meinolf Geck

We consider the set $\Irr(W)$ of (complex) irreducible characters of a finite Coxeter group $W$. The Kazhdan--Lusztig theory of cells gives rise to a partition of $\Irr(W)$ into &#34;families&#34; and to a natural partial order $\leq_{\cLR}$ on these families. Following an idea of Spaltenstein, we show that $\leq_{\cLR}$ can be characterised (and effectively

Soummya Kar, Jose Moura

We characterize the invariant filtering measures resulting from Kalman filtering with intermittent observations (\cite{Bruno}), where the observation arrival is modeled as a Bernoulli process. In \cite{Riccati-weakconv}, it was shown that there exists a $\overlineγ^{\{\scriptsize{sb}}}>0$ such that for every observation packet arrival probability $\overlineγ

G. V. Lopez, E. M. Juarez

We study two-bodies gravitational problem where the mass of one of the bodies varies and suffers a damping-antidamping effect due to star wind during its motion. A constant of motion, a Lagrangian and a Hamiltonian are given for the radial motion of the system, and the period of the body is studied using the constant of motion of the system. An application t

Fedor Zhdanov, Vladimir Vovk

We study the problem of online regression. We prove a theoretical bound on the square loss of Ridge Regression. We do not make any assumptions about input vectors or outcomes. We also show that Bayesian Ridge Regression can be thought of as an online algorithm competing with all the Gaussian linear experts.

P. V. Buividovich, M. N. Chernodub, E. V. Luschevskaya, M. I. Polikarpov

A possible experimental observation of the chiral magnetic effect in heavy ion collisions at RHIC was recently reported by the STAR Collaboration. We study signatures of this effect in SU(2) lattice gluodynamics with the chirally invariant Dirac operator. We find that at zero temperature the local fluctuations of an electric current of quarks and chirality f

Alexander Kelmans

An L-factor of a graph G is a spanning subgraph of G whose every component is a 3-vertex path. Let v(G) be the number of vertices of G and d(G) the domination number of G. A claw is a graph with four vertices and three edges incident to the same vertex. A graph is claw-free if it has no induced subgraph isomorphic to a claw. Our results include the following

Lasse Rempe

We show that for many complex parameters a, the set of points that converge to infinity under iteration of the exponential map f(z)=e^z+a is connected. This includes all parameters for which the singular value escapes to infinity under iteration.

Feng Xiong, Albert Liao, Eric Pop

Carbon nanotube (CNT) heaters with sub-5 nm diameter induce highly localized phase change in Ge2Sb2Te5 (GST) chalcogenide. A significant reduction in resistance of test structures is measured as the GST near the CNT heater crystallizes. Effective GST heating occurs at currents as low as 25 uA, significantly lower than in conventional phase change memory with

H. Sims, S. J. Oset, W. H. Butler, James M. MacLaren

We report a study of the anisotropic exchange interactions in bulk CrO_2 calculated from first principles within density functional theory. We determine the exchange coupling energies, using both the experimental lattice parameters and those obtained within DFT, within a modified Heisenberg model Hamiltonian in two ways. We employ a supercell method in which

Z. Hradil, J. Rehacek, A. B. Klimov, I. Rigas

The uncertainty principle places a fundamental limit on the accuracy with which we can measure conjugate physical quantities. However, the fluctuations of these variables can be assessed in terms of different estimators. We propose a new angular performance that allows for tighter uncertainty relations for angle and angular momentum. The differences with pre

Christian Borghesi

We study spatiotemporal regularities of electoral results and turnout rates for each municipality (or polling station) concerning French elections between 1992 and 2007. We try to account for the data using models based on a simple imitation of agents in the vicinity. We also propose a model of an experiment that shows how choices are modified by knowing the

Luisa Consiglieri

This paper addresses a nonstationary flow of heat-conductive incompressible Newtonian fluid with temperature-dependent viscosity coupled with linear heat transfer with advection and a viscous heat source term, under Navier/Dirichlet boundary conditions. The partial regularity for the velocity of the fluid is proved to each proper weak solution, that is, for

Noah Graham, Alexander Shpunt, Thorsten Emig, Sahand Jamal Rahi

The Casimir force has been computed exactly for only a few simple geometries, such as infinite plates, cylinders, and spheres. We show that a parabolic cylinder, for which analytic solutions to the Helmholtz equation are available, is another case where such a calculation is possible. We compute the interaction energy of a parabolic cylinder and an infinite

V. I. Kuksa, R. S. Pasechnik

Near-threshold production of boson pairs is considered within the framework of the model of unstable particles with smeared mass. We describe the principal aspects of the model and consider the strategy of calculations including the radiative corrections. The results of calculations are in good agreement with LEP II data and Monte-Carlo simulations. Suggeste

Andrea Lubberdink

If, in a system of identical particles, the one particle state is defined by the partial trace to one of the component spaces of the total Hilbert space, then all one particle states are identical. The particles are indistinguishable. This is often thought to be a typical quantum mechanical phenomenon. I will show however that an analogous procedure to defin

J. Lember

We consider the smoothing probabilities of hidden Markov model (HMM). We show that under fairly general conditions for HMM, the exponential forgetting still holds, and the smoothing probabilities can be well approximated with the ones of double sided HMM. This makes it possible to use ergodic theorems. As an applications we consider the pointwise maximum a p

Tamifusa Matsuura, Hidenori Suzuki, Ken&#39;ichi Takano, Fumihiro Honda

We propose a general formula for the melting temperature of metals in terms of electronic mass, electronic number, and nearest-neighbor lattice distance. We derive it from the instability of the transverse phonon in the solid phase, using the nearly free electron model. Including higher order terms of vibrations enhanced near the melting temperature, the ele