April 2010 arXiv papers — page 4

Sarah Filippi, Olivier Cappé, Aurélien Garivier

We consider model-based reinforcement learning in finite Markov De- cision Processes (MDPs), focussing on so-called optimistic strategies. In MDPs, optimism can be implemented by carrying out extended value it- erations under a constraint of consistency with the estimated model tran- sition probabilities. The UCRL2 algorithm by Auer, Jaksch and Ortner (2009)

Matthew G. Walker, Stacy S. McGaugh, Mario Mateo, Edward Olszewski

We consider dark masses measured from kinematic tracers at discrete radii in galaxies for which baryonic contributions to overall potentials are either subtracted or negligible. Recent work indicates that rotation curves due to dark matter (DM) halos at intermediate radii in spiral galaxies are remarkably similar, with a mean rotation curve given by $\log_{1

Mats Ehrnström, Joachim Escher, Erik Wahlén

We construct small-amplitude periodic water waves with multiple critical layers. In addition to waves with arbitrarily many critical layers and a single crest in each period, two-dimensional sets of waves with several crests and troughs in each period are found. The setting is that of steady two-dimensional finite-depth gravity water waves with vorticity.

T. Wakasa

We performed the multipole decomposition analysis (MDA) for the ${}^{208}{\rm Pb}(p,n)$ data in order to obtain the spin-dipole (SD) strengths separated into each $\Delta J^{\pi}$ contribution $dB({\rm SD}_{\Delta J^{\pi}};\omega)/d\omega$. The random phase approximation (RPA calculations reproduce the total SD strength reasonably well, whereas some discrepa

N. Cappelluti, P. Predehl, H. Boehringer, H. Brunner

eROSITA (extended ROentgen Survey with an Imaging Telescope Array) is the core instrument on the Russian Spektrum-Roentgen-Gamma (SRG) mission which is scheduled for launch in late 2012. eROSITA is fully approved and funded by the German Space Agency DLR and the Max-Planck-Society. The design driving science is the detection of 50 - 100 thousands Clusters of

Anne-Florence Bitbol, Paul G. Dommersnes, Jean-Baptiste Fournier

Although Casimir forces are inseparable from their fluctuations, little is known about these fluctuations in soft matter systems. We use the membrane stress tensor to study the fluctuations of the membrane-mediated Casimir-like force. This method enables us to recover the Casimir force between two inclusions and to calculate its variance. We show that the Ca

Matteo Gorgoglione, Valentin Savin, David Declercq

In this paper we design non-uniform bit-wise puncturing distributions for irregular non-binary LDPC (NB-LDPC) codes. The puncturing distributions are optimized by minimizing the decoding threshold of the punctured LDPC code, the threshold being computed with a Monte-Carlo implementation of Density Evolution. First, we show that Density Evolution computed wit

M. Colonna, A. Ono, J. Rizzo

We undertake a quantitative comparison of multi-fragmentation reactions, as modeled by two different approaches: the Antisymmetrized Molecular Dynamics (AMD) and the momentum-dependent stochastic mean-field (SMF) model. Fragment observables and pre-equilibrium (nucleon and light cluster) emission are analyzed, in connection to the underlying compression-expa

Christian Gérard, Fumio Hiroshima, Annalisa Panati, Akito Suzuki

We consider the Nelson model with variable coefficients and investigate the problem of existence of a ground state and the removal of the ultraviolet cutoff. Nelson models with variable coefficients arise when one replaces in the usual Nelson model the flat Minkowski metric by a static metric, allowing also the boson mass to depend on position. A physical ex

Jean-Philippe Anker, Fatma Ayadi, Mohamed Sifi

Let $G_λ^{(α,β)}$ be the eigenfunctions of the Dunkl-Cherednik operator $T^{(α,β)}$ on $\mathbb{R}$. In this paper we express the product $G_λ^{(α,β)}(x)G_λ^{(α,β)}(y)$ as an integral in terms of $G_λ^{(α,β)}(z)$ with an explicit kernel. In general this kernel is not positive. Furthermore, by taking the so-called rational limit, we recover the product formul

Mathieu Marciante, Caroline Champenois, Annette Calisti, Jofre Pedregosa-Gutierrez

We analyse the possibility of cooling ions with a single laser beam, due to the coupling between the three components of their motion induced by the Coulomb interaction. For this purpose, we numerically study the dynamics of ion clouds of up to 140 particles, trapped in a linear quadrupole potential and cooled with a laser beam propagating in the radial plan

Sylvain Lavernhe, Christophe Tournier, Claire Lartigue

Apr\`es avoir d\'etaill\'e les principales difficult\'es li\'ees \`a l'usinage 5 axes UGV, nous pr\'esentons un mod\`ele de repr\'esentation des trajectoires 5 axes sous forme surfacique permettant de prendre en compte des contraintes g\'eom\'etriques et cin\'ematiques. Ce mod\`ele est int\'egr\'e dans d'optimisation des trajets 5 axes afin de maximiser la p

Nalini Anantharaman, Fabricio Macià

In this article, the structure of semiclassical measures for solutions to the linear Schrödinger equation on the torus is analysed. We show that the disintegration of such a measure on every invariant lagrangian torus is absolutely continuous with respect to the Lebesgue measure. We obtain an expression of the Radon-Nikodym derivative in terms of the sequenc

Ouerdia Arkoun

We constuct a sequential adaptive procedure for estimating the autoregressive function at a given point in nonparametric autoregression models with Gaussian noise. We make use of the sequential kernel estimators. The optimal adaptive convergence rate is given as well as the upper bound for the minimax risk.

Camille Ducoin, Jérôme Margueron, Constança Providencia

The slope of the nuclear symmetry energy at saturation density $L$ is pointed out as a crucial quantity to determine the mass and width of neutron-star crusts. This letter clarifies the relation between $L$ and the core-crust transition. We confirm that the transition density is soundly correlated with $L$ despite differences between models, and we propose a

Valentin Bonzom, Matteo Smerlak

We consider a class of lattice topological field theories, among which are the weak-coupling limit of 2d Yang-Mills theory, the Ponzano-Regge model of 3d quantum gravity and discrete BF theory, whose dynamical variables are flat discrete connections with compact structure group on a cell 2-complex. In these models, it is known that the path integral measure

Pascal Azerad, Afaf Bouharguane, Jean-François Crouzet

In this paper, a new filtering method is presented for simultaneous noise reduction and enhancement of signals using a fractal scalar conservation law which is simply the forward heat equation modified by a fractional anti-diffusive term of lower order. This kind of equation has been first introduced by physicists to describe morphodynamics of sand dunes. To

N. El Karoui, Mohamed M'Rad

The paper generalizes the construction by stochastic flows of consistent utility processes introduced by M. Mrad and N. El Karoui in (2010). The utilities random fields are defined from a general class of processes denoted by $\GX$. Making minimal assumptions and convex constraints on test-processes, we construct by composing two stochastic flows of homeomor

Nicole El Karoui, Mohamed Mrad

Motivated by the work of Musiela and Zariphopoulou \cite{zar-03}, we study the Itô random fields which are utility functions $U(t,x)$ for any $(ω,t)$. The main tool is the marginal utility $U_x(t,x)$ and its inverse expressed as the opposite of the derivative of the Fenchel conjuguate $\tU(t,y)$. Under regularity assumptions, we associate a $SDE(μ, σ)$ and i

Jian Cui, Jun-Peng Cao, Heng Fan

Kitaev honeycomb model with topological phase transition at zero temperature is studied using quantum information method. Based on the exact solution of the ground state, the mutual information between two nearest sites and between two bonds with longest distance are obtained. It is found that the mutual information show some singularities at the critical po

T. Paterek, P. Kurzynski, D. K. L. Oi, D. Kaszlikowski

Superselection rules (SSRs) constrain the allowed states and operations in quantum theory. They limit preparations and measurements hence impact upon our ability to observe non-locality, in particular the violation of Bell inequalities. We show that a reference frame compatible with a particle number SSR does not allow observers to violate a Bell inequality

Monireh Houshmand, Saied Hosseini-Khayat, Mark M. Wilde

One of the major goals in quantum information processing is to reduce the overhead associated with the practical implementation of quantum protocols, and often, routines for quantum error correction account for most of this overhead. A particular technique for quantum error correction that may be useful for protecting a stream of quantum information is quant

Jianqing Fan, Shaojun Guo, Ning Hao

Variance estimation is a fundamental problem in statistical modeling. In ultrahigh dimensional linear regressions where the dimensionality is much larger than sample size, traditional variance estimation techniques are not applicable. Recent advances on variable selection in ultrahigh dimensional linear regressions make this problem accessible. One of the ma

G. Y. Chen, H. R. Dong, J. P. Ma

The observed enhancement of $p\bar p$-production near the threshold in radiative decays of $J/ψ$ and $e^+e^-$-annihilations can be explained with final state interactions among the produced $N\bar N$ system, where the enhancement is essentially determined by $N\bar N$ elastic scattering amplitudes. We propose to use an effective theory for interactions in a

Osamu Fujino, Karl Schwede, Shunsuke Takagi

We consider various definitions of non-lc ideal sheaves -- generalizations of the multiplier ideal sheaf which define the non-lc (non-log canonical) locus. We introduce the maximal non-lc ideal sheaf and intermediate non-lc ideal sheaves and consider the restriction theorem for these ideal sheaves. We also begin the development of the theory of a characteris

Xi Chen, James D. Lewis

We proved that the union of rational curves is dense on a very general K3 surface and the union of elliptic curves is dense in the 1st jet space of a very general K3 surface, both in the strong topology.

Eric Patterson

We show that the singular loci of graph hypersurfaces correspond set-theoretically to their rank loci. The proof holds for all configuration hypersurfaces and depends only on linear algebra. To make the conclusion for the second graph hypersurface, we prove that the second graph polynomial is a configuration polynomial. The result indicates that there may be

Urban Larsson

In this paper we study a family of 2-pile Take Away games, that we denote by Generalized Diagonal Wythoff Nim (GDWN). The story begins with 2-pile Nim whose sets of options and $P$-positions are $\{\{0,t\}\mid t\in \N\}$ and $\{(t,t)\mid t\in \M \}$ respectively. If we to 2-pile Nim adjoin the main-\emph{diagonal} $\{(t,t)\mid t\in \N\}$ as options, the new

Claudio Conti, Sebastian Stark, Philip St. J. Russell, Fabio Biancalana

We theoretically predict the occurrence of multiple hydrodynamical-like shock phenomena in the propagation of ultrashort intense pulses in a suitably engineered photonic crystal fiber. The shocks are due to the Raman effect, which acts as a nonlocal term favoring their generation in the focusing regime. It is shown that the problem is mapped to shock formati

Małgorzata Stawiska

We study asymptotics of integrals of certain rational functions that depend on parameters in a field $K$ of characteristic zero. We use formal power series to represent the integral and prove certain identities about its coefficients following from generalized Vandermonde determinant expansion. Our result can be viewed as a parametric version of a classical

I-Hsiang Wang, David N. C. Tse

Interference limits performance in wireless networks, and cooperation among receivers or transmitters can help mitigate interference by forming distributed MIMO systems. Earlier work shows how limited receiver cooperation helps mitigate interference. The scenario with transmitter cooperation, however, is more difficult to tackle. In this paper we study the t

Andrea Micheli, Zbigniew Idziaszek, Guido Pupillo, Mikhail A. Baranov

Analytic expressions describe universal elastic and reactive rates of quasi-two-dimensional and quasi-one-dimensional collisions of highly reactive ultracold molecules interacting by a van der Waals potential. Exact and approximate calculations for the example species of KRb show that stability and evaporative cooling can be realized for spin-polarized fermi

R. J. Assef, C. S. Kochanek, The AGES Collaboration

We present a set of low resolution empirical SED templates for AGNs and galaxies in the wavelength range from 0.03 to 30 microns. These templates form a non-negative basis of the color space of such objects and have been derived from a combination 14448 galaxies and 5347 likely AGNs in the NDWFS Bootes field. We briefly describe how the templates are derived

Konstantin Batygin, Michael E. Brown

In the recent years, the "Nice" model of solar system formation has attained an unprecedented level of success in reproducing much of the observed orbital architecture of the solar system by evolving the planets to their current locations from a more compact configuration. Within the context of this model, the formation of the classical Kuiper belt r

Sandip Pakvasa

It is shown how high energy neutrino beams from very distant sources can be utilised to learn about many neutrino properties such as lifetimes, mass hierarchy, mixing, minuscule pseudo-Dirac mass splittings and other exotic properties. In addition, the production mechanism of neutrinos in the astrophysical sources can also be elucidated.

Adom Giffin, Mikhail Shneider, Chiranjeev S. Kalra, T. L. Ames

We examine several conducting spheres moving through a magnetic field gradient. An analytical approximation is derived and an experiment is conducted to verify the analytical solution. The experiment is simulated as well to produce a numerical result. Both the low and high magnetic Reynolds number regimes are studied. Deformation of the sphere is noted in th

Zhenwei Cao, Alexander Elgart

Enthusiast's perspective: We analyze the effectiveness of AQC for a small rank problem Hamiltonian $H_F$ with the arbitrary initial Hamiltonian $H_I$. We prove that for the generic $H_I$ the running time cannot be smaller than $O(\sqrt N)$, where $N$ is a dimension of the Hilbert space. We also construct an explicit $H_I$ for which the running time is in

Adom Giffin

It has been previously shown that one can use the ME methodology (Caticha Giffin 2006) to reproduce a mean field solution for a simple fluid (Tseng 2004). One could easily use the case of a simple ferromagnetic material as well. The drawback to the mean field approach is that one must assume that all atoms must all act the same. The problem becomes more trac

Robert M. Strain

We study the Cauchy Problem for the relativistic Boltzmann equation with near Vacuum initial data. Unique global in time "mild" solutions are obtained uniformly in the speed of light parameter $c \ge 1$. We furthermore prove that solutions to the relativistic Boltzmann equation converge to solutions of the Newtonian Boltzmann equation in the limit as

Zhijun Xu, Jinsheng Wen, Guangyong Xu, C. Stock

We report measurements of the neutron diffuse scattering in a single crystal of the relaxor ferroelectric material 95.5%Pb(Zn$_{1/3}$Nb$_{2/3}$)O$_3$-4.5%PbTiO$_3$ (PZN-4.5%PT). Our results suggest that the nanometer scale structure in this compound exhibits both $<100>$ and $<110>$ polarizations, which contribute to different portions of the total diffuse s

C. J. Evans, N. R. Walborn, P. A. Crowther, V. Henault-Brunet

We present the first ultraviolet (UV) and multi-epoch optical spectroscopy of 30 Dor 016, a massive O2-type star on the periphery of 30 Doradus in the Large Magellanic Cloud. The UV data were obtained with the Cosmic Origins Spectrograph on the Hubble Space Telescope as part of the Servicing Mission Observatory Verification program after Servicing Mission 4,

John Ellis, Azar Mustafayev, Keith A. Olive

In the context of phenomenological models in which the soft supersymmetry-breaking parameters of the MSSM become universal at some unification scale, M_{in}, above the GUT scale, \mgut, it is possible that all the scalar mass parameters m_0, the trilinear couplings A_0 and the bilinear Higgs coupling B_0 vanish simultaneously, as in no-scale supergravity. Us

A. M. Fedotov, N. B. Narozhny, G. Mourou, G. Korn

It is shown that even a single $e^-e^+$ pair created by a super strong laser field in vacuum would cause development of an avalanche-like QED cascade which rapidly depletes the incoming laser pulse. This confirms the old N. Bohr conjecture that the electric field of the critical QED strength $E_S=m^2c^3/e\hbar$ could never be created.

Yonathan Schwarzkopf, Robert L. Axtell, J. Doyne Farmer

Phenomena as diverse as breeding bird populations, the size of U.S. firms, money invested in mutual funds, the GDP of individual countries and the scientific output of universities all show unusual but remarkably similar growth fluctuations. The fluctuations display characteristic features, including double exponential scaling in the body of the distribution

Raj Gandhi

We discuss the physics capabilities of basic types of future atmospheric detectors being considered at present, with their strengths and limitations, and compare them with those of long baseline (LBL) experiments. We also argue that recent studies signal the importance of synergistically combining complementary features of both these classes of experiments i

G. Dupont, S. Guenneau, S. Enoch

We design three dimensional electromagnetic cloaks, starting from a small region of complex shape instead of a point. We derive the expression of a transformation matrix describing an objet with a surface of revolution and its associated non-singular cloak. We note that while none of the eigenvalues vanish inside the cloak, they suffer a discontinuity on its

David B. Fisher, Niv Drory

We investigate scaling relations of bulges using bulge-disk decompositions at 3.6 micron and present bulge classifications for 173 E-Sd galaxies within 20 Mpc. Pseudobulges and classical bulges are identified using Sersic index, HST morphology, and star formation activity (traced by 8 micron emission). In the near-IR pseudobulges have n_b<2 and classical bul

Liying Jiao, Li Zhang, Lei Ding, Jie Liu

Aligned graphene nanoribbon (GNR) arrays were made by unzipping of aligned single-walled and few-walled carbon nanotube (CNT) arrays. Nanotube unzipping was achieved by a polymer-protected Ar plasma etching method, and the resulting nanoribbon array was transferred onto any substrates. Atomic force microscope (AFM) imaging and Raman mapping on the same CNTs

Pye-Ton How, André LeClair

A new analytic treatment of three-dimensional homogeneous Bose and Fermi gases in the unitary limit of negative infinite scattering length is presented, based on the S-matrix approach to statistical mechanics we recently developed. The unitary limit occurs at a fixed point of the renormalization group with dynamical exponent z=2 where the S-matrix equals -1.

P. Cossins, G. Lodato, L. Testi

In this paper we present simulated observations of massive self-gravitating circumstellar discs using the Atacama Large Millimetre/sub-millimetre Array (ALMA). Using a smoothed particle hydrodynamics model of a $0.2M_{\odot}$ disc orbiting a $1M_{\odot}$ protostar, with a cooling model appropriate for discs at temperatures below $\sim 160$K and representativ

E. Sharpe

In this short note we give an overview of recent work on string propagation on stacks and applications to gauged linear sigma models. We begin by outlining noneffective orbifolds (orbifolds in which a subgroup acts trivially) and related phenomena in two-dimensional gauge theories, which realize string propagation on gerbes. We then discuss the `decompositio

Joshua L. Davis, Thomas S. Levi, Mark Van Raamsdonk, Kevin R. L. Whyte

We present a new mechanism for slow-roll inflation based on higher dimensional supersymmetric gauge theory compactified to four dimensions with twisted (supersymmetry breaking) boundary conditions. These boundary conditions lead to a potential for directions in field space that would have been flat were supersymmetry preserved. For field values in these dire

Vitor M. Pereira, A. H. Castro Neto, H. Y. Liang, L. Mahadevan

As the thinnest atomic membrane, graphene presents an opportunity to combine geometry, elasticity and electronics at the limits of their validity. The availability of reliable atomistic potentials for graphene allows unprecedented precise simulations of the mechanical response of atomic membranes. Here we describe the transport and electronic structure in th

Nissim Kanekar, Jayaram N. Chengalur, Tapasi Ghosh

We report Westerbork Synthesis Radio Telescope and Arecibo Telescope observations of the redshifted satellite OH-18cm lines at $z \sim 0.247$ towards PKS1413+135. The &#34;conjugate&#34; nature of these lines, with one line in emission and the other in absorption, but with the same shape, implies that the lines arise in the same gas. The satellite OH-18cm li

Pritam Roy

Verification of software systems is a very hard problem due to the large size of program state-space. The traditional techniques (like model checking) do not scale; since they include the whole state-space by inlining the library function codes. Current research avoids these problem by creating a lightweight representation of the library in form of an &#34;i

A. Brandenburg, P. Chatterjee, F. Del Sordo, A. Hubbard

The predictive power of mean-field theory is emphasized by comparing theory with simulations under controlled conditions. The recently developed test-field method is used to extract turbulent transport coefficients both in kinematic as well as nonlinear and quasi-kinematic cases. A striking example of the quasi-kinematic method is provided by magnetic buoyan

P. G. Jonker, M. A. P. Torres, A. C. Fabian, M. Heida

In this Paper we report the discovery of CXO J122518.6+144545; a peculiar X-ray source with a position 3.6+-0.2&#34;,off-nuclear from an SDSS DR7 z=0.0447 galaxy. The 3.6&#34; offset corresponds to 3.2 kpc at the distance of the galaxy. The 0.3-8 keV X-ray flux of this source is 5x10^-14 erg cm^-2 s^-1 and its 0.3-8 keV luminosity is 2.2x10^41 erg/s (2.7x10^

Jean-Rene Gauthier, Hsiao-Wen Chen, Jeremy Tinker

We present the first results of an ongoing spectroscopic follow-up of close luminous red galaxy (LRGs) and MgII λλ 2796,2803 absorber pairs for an initial sample of 15 photometrically selected LRGs at physical projected separations ρ \le 350 kpc/h from a QSO sightline. Our moderate-resolution spectra confirm a physical association between the cool gas (T ~ 1

John S. Mulchaey, Tesla E. Jeltema

We use Chandra and XMM-Newton to study the hot gas content in a sample of field early-type galaxies. We find that the L_X-L_K relationship is steeper for field galaxies than for comparable galaxies in groups and clusters. The low hot gas content of field galaxies with L_K < L_star suggests that internal processes such as supernovae driven winds or AGN feedba

Yu. P. Goncharov, N. E. Firsova

The confinement mechanism proposed earlier and then applied successfully to meson spectroscopy by one of the authors is interpreted in classical terms. For this aim the unique solution of the Maxwell equations, an analog of the corresponding unique solution of the SU(3)-Yang-Mills equations describing linear confinement in quantum chromodynamics, is used. Mo

Dell Zhang, Jun Wang, Deng Cai, Jinsong Lu

The ability of fast similarity search at large scale is of great importance to many Information Retrieval (IR) applications. A promising way to accelerate similarity search is semantic hashing which designs compact binary codes for a large number of documents so that semantically similar documents are mapped to similar codes (within a short Hamming distance)

Muhammad Adnan Shahzad

The problem of diffraction of an electromagnetic plane wave by a perfectly conducting circular disk and its complementary problem, diffraction by a circular hole in an infinite conducting plate, are rigorously solved using the method of the Kobayashi potential. The mathematical formulation involved dual integral equation derived from the potential integral a

Christian Bartsch, Robin Steinigeweg, Jochen Gemmer

We aim at deriving an equation of motion for specific sums of momentum mode occupation numbers from models for electrons in periodic lattices experiencing elastic scattering, electron-phonon scattering or electron-electron scattering. These sums correspond to &#34;grains&#34; in momentum space. This equation of motion is supposed to involve only a moderate n

Cesar A. Valenzuela-Toledo

We study the statistical descriptors for some cosmological inflationary models that allow us to get large levels of non-gaussianity and violations of statistical isotropy. Basically, we study two different class of models: a model that include only scalar field perturbations, specifically a subclass of small-field slow-roll models of inflation with canonical

L. Zappacosta, F. Nicastro, R. Maiolino, G. Tagliaferri

We make use of a 500ks Chandra HRC-S/LETG spectrum of the blazar H2356-309, combined with a lower S/N spectrum of the same target, to search for the presence of warm-hot absorbing gas associated with two Large-Scale Structures (LSSs) crossed by this sightline at z=0.062 (the Pisces-Cetus Supercluster, PCS) and at z=0.128 (&#34;Farther Sculptor Wall&#34;, FSW

Juthika Khargharia, Cynthia S. Froning, Edward L. Robinson

We present near-infrared (NIR) broadband (0.80--2.42 $μ$m) spectroscopy of two low mass X-ray binaries: V404 Cyg and Cen X-4. One important parameter required in the determination of the mass of the compact objects in these systems is the binary inclination. We can determine the inclination by modeling the ellipsoidal modulations of the Roche-lobe filling do

Leonid Bedratyuk

A method based on the symbolic methods of the classical invariant theory is developed for a representation of elements of kernel of Weitzenbök derivations.

A. P. Veselov

It is shown that the four-parameter family of elliptic functions $$u_D(z)=m_0(m_0+1)\wp(z)+\sum_{i=1}^3 m_i(m_i+1)\wp(z-ω_i)$$ introduced by Darboux and rediscovered a hundred years later by Treibich and Verdier, is the most general meromorphic family containing infinitely many finite-gap potentials.

Kristina Lerman, Tad Hogg

Popularity of content in social media is unequally distributed, with some items receiving a disproportionate share of attention from users. Predicting which newly-submitted items will become popular is critically important for both companies that host social media sites and their users. Accurate and timely prediction would enable the companies to maximize re

Markus A. Mangold, Christoph Weiss, Beate Dirks, Alexander W. Holleitner

We study the impact of optical field-enhancement effects on the optoelectronic properties of metal nanoparticle arrays. Applying a focused ion beam lithography in combination with an electron beam deposition technique we can pattern electrical contacts in a way to give rise to an electromagnetic field-enhancement. A further field-enhancement is achieved by t

Manuel Greschek, Martin Schoen

We present Monte Carlo simulations of liquid-crystalline material confined to a nanoscopic slit-pore. The simulations are carried out under isothermal conditions in a specialized isostress ensemble in which N fluid molecules are exposed to a compressional stress acting on the fluid in directions parallel with the substrate planes. Fluid-fluid and fluid-subst

Alexander V. Mikhailov, Jing Ping Wang, Pavlos Xenitidis

In this paper we make an attempt to give a consistent background and definitions suitable for the theory of integrable difference equations. We adapt a concept of recursion operator to difference equations and show that it generates an infinite sequence of symmetries and canonical conservation laws for a difference equation. Similar to the case of partial di

Amie Wilkinson

We discuss recent progress in understanding the dynamical properties of partially hyperbolic diffeomorphisms that preserve volume. The main topics addressed are density of stable ergodicity and stable accessibility, center Lyapunov exponents, pathological foliations, rigidity, and the surprising interrelationships between these notions.

Erwan Lanneau, Jean-Luc Thiffeault

We find the minimum dilatation of pseudo-Anosov braids on n-punctured discs for 3 <= n <= 8. This covers the results of Song-Ko-Los (n=4) and Ham-Song (n=5). The proof is elementary, and uses the Lefschetz formula.

Isaac DeFrain, Mitch Phillipson, Simei Tong

Understanding the complemented subspaces of $L_p$ has been an interesting topic of research in Banach space theory since 1960. 1999, Alspach proposed a systematic approach to classifying the subspaces of $L_p$ by introducing a norm given by partitions and weights. This paper shows that with Alspach Norm we are able to classify some complemented subspaces of

John Voight

We extend methods of Greenberg and the author to compute in the cohomology of a Shimura curve defined over a totally real field with arbitrary class number. Via the Jacquet-Langlands correspondence, we thereby compute systems of Hecke eigenvalues associated to Hilbert modular forms of arbitrary level over a totally real field of odd degree. We conclude with

Mark S. Veillette, Murad S. Taqqu

We want to compute the cumulative distribution function of a one-dimensional Poisson stochastic integral $I(\krnl) = \displaystyle \int_0^T \krnl(s) N(ds)$, where $N$ is a Poisson random measure with control measure $n$ and $\krnl$ is a suitable kernel function. We do so by combining a Kolmogorov-Feller equation with a finite-difference scheme. We provide th

Nobuhiko Watari, Ronald G. Larson

We propose minimal models of one-, two- and three-dimensional micro-swimmers at low Reynolds number with a periodic non-reciprocal motion. These swimmers are either &#34;pushers&#34; or &#34;pullers&#34; of fluid along the swimming axis, or combination of the two, depending on the history of the swimming motion. We show this with a linear three-bead swimmer

D. J. Mowbray, J. M. Garcia-Lastra, K. S. Thygesen, A. Rubio

We demonstrate a &#34;bottom up&#34; approach to the computational design of a multifunctional chemical sensor. General techniques are employed for describing the adsorption coverage and resistance properties of the sensor based on density functional theory (DFT) and non-equilibrium Green&#39;s function methodologies (NEGF), respectively. Specifically, we sh

Leo van Iersel, Steven Kelk

Rooted phylogenetic networks are often constructed by combining trees, clusters, triplets or characters into a single network that in some well-defined sense simultaneously represents them all. We review these four models and investigate how they are related. In general, the model chosen influences the minimum number of reticulation events required. However,

Siti S. Jamaian, Tom G. Mackay

The Bruggeman formalism provides an estimate $\eps^{Br}_{hcm}$ of the relative permittivity of a homogenized composite material (HCM), arising from two component materials with relative permittivities $\eps_a$ and $\eps_b$. It can be inverted to provide an estimate of $\eps_a$, from a knowledge of $\eps^{Br}_{hcm}$ and $\eps_b$. Numerical studies show that t

Michael J. Barber, John W. Clark

We introduce a class of neural networks derived from probabilistic models in the form of Bayesian networks. By imposing additional assumptions about the nature of the probabilistic models represented in the networks, we derive neural networks with standard dynamics that require no training to determine the synaptic weights, that perform accurate calculation

David Campo

I critically examine various ad hoc models describing a fundamental minimal length at the level of the propagator. They violate causality and/or unitarity.

K. A. Weaver, M. Meléndez, R. F. Mushotzky, S. Kraemer

We compare mid-infrared emission-line properties, from high-resolution Spitzer spectra of a hard X-ray (14 -- 195 keV) selected sample of nearby (z < 0.05) AGN detected by the Burst Alert Telescope (BAT) aboard Swift. The luminosity distribution for the mid-infrared emission-lines, [O IV] 25.89 micron, [Ne II] 12.81 micron, [Ne III] 15.56 micron and [Ne V] 1

Alexander N. McClymont, George H. Fisher

Where does solar flare energy come from? More specifically, assuming that the ultimate source of flare energy is mechanical energy in the convection zone, how is this translated into energy dissipated or stored in the corona? This question appears to have been given relatively little thought, as attention has been focussed predominantly on mechanisms for the

Xin Wu, Yi Xie

This paper is mainly devoted to applying the invariant, fast, Lyapunov indicator to clarify some doubt regarding the apparently conflicting results of chaos in spinning compact binaries at the second-order post-Newtonian approximation of general relativity from previous literatures. It is shown with a number of examples that no single physical parameter or i

Shun-Tsung Lo, Kuang Yao Chen, T. L. Lin, Li-Hung Lin

We have performed low-temperature transport measurements on a disordered two-dimensional electron system (2DES). Features of the strong localization leading to the quantum Hall effect are observed after the 2DES undergoes a direct insulator-quantum Hall transition with increasing the perpendicular magnetic field. However, such a transition does not correspon

Wanzhou Zhang, Wenan Guo, Kaj H Hoglund, Ling Wang

We study the distribution of local magnetic susceptibilities in the two-dimensional antiferromagnetic S=1/2 Heisenberg model on various random clusters, in order to determine whether effects of edge disorder could be detected in NMR experiments (through the line shape, as given by the distribution of local Knight shifts). Although the effects depend strongly

Nigel Hitchin

We introduce an algebra of Schouten-commuting holomorphic polyvector fields on the moduli space of stable G-bundles over a curve by using invariant forms on the Lie algebra. The generators begin in degree three -- we prove a vanishing theorem for degree two in the case of G=GL(n).

D. Levi, P. Winternitz, R. Yamilov

We present an algorithm for determining the Lie point symmetries of differential equations on fixed non transforming lattices, i.e. equations involving both continuous and discrete independent variables. The symmetries of a specific integrable discretization of the Krichever-Novikov equation, the Toda lattice and Toda field theory are presented as examples o

Anna Elisabeth Böhmer, Marcin Konczykowski, Cornelis Jacominus Van Der Beek

Magneto-optical imaging and Hall-probe array magnetometry are used to measure the field of first flux entry, H_p, into the same Bi_2Sr_2CaCu_2O_8+delta single crystal cut to different crystal thickness-to-width ratios (d/w), and for two angles alpha between the edges and the principal in-plane crystalline (a,b) axes. At all temperatures, the variation with a

Chinh T. Hoàng, Frédéric Maffray, Meriem Mechebbek

A b-coloring is a coloring of the vertices of a graph such that each color class contains a vertex that has a neighbor in all other color classes, and the b-chromatic number of a graph $G$ is the largest integer $k$ such that $G$ admits a b-coloring with $k$ colors. A graph is b-perfect if the b-chromatic number is equal to the chromatic number for every ind

Marcio Marim, Michael Atlan, Elsa Angelini, Jean-Christophe Olivo-Marin

This work reveals an experimental microscopy acquisition scheme successfully combining Compressed Sensing (CS) and digital holography in off-axis and frequency-shifting conditions. CS is a recent data acquisition theory involving signal reconstruction from randomly undersampled measurements, exploiting the fact that most images present some compact structure

Yuan Zhou

The author establishes some geometric criteria for a domain of ${\mathbb R}^n$ with $n\ge2$ to support a $(pn/(n-ps),\,p)_s$-Hajłasz-Sobolev-Poincaré imbedding with $s\in(0,\,1]$ and $p\in(n/(n+s),\,n/s)$ or an $s$-Hajłasz-Trudinger imbedding with $s\in(0,\,1]$.

Konrad H Marti, Bela Bauer, Markus Reiher, Matthias Troyer

We present a new class of tensor network states that are specifically designed to capture the electron correlation of a molecule of arbitrary structure. In this ansatz, the electronic wave function is represented by a Complete-Graph Tensor Network (CGTN) ansatz which implements an efficient reduction of the number of variational parameters by breaking down t

Moussa Balde, Philippe Jouan

The paper is concerned with asymptotic stability properties of linear switched systems. Under the hypothesis that all the subsystems share a non strict quadratic Lyapunov function, we provide a large class of switching signals for which a large class of switched systems are asymptotically stable. For this purpose we define what we call non chaotic inputs, wh

M. Blank, A. Krassnigg

We analyze the chiral phase transition with the help of the QCD gap equation. Various models for the effective interaction in rainbow truncation are contrasted with regard to the resulting chiral transition temperatures. In particular, we investigate possible systematic relations of the details of the effective interaction and the value of T_c. In addition,

Chihiro Sasaki

We discuss phases in dense hadronic and quark matter from chiral model approaches. Within PNJL models the phase diagram for various number of colors $N_c$ is studied. How phases are constrained in quantum field theories are also discussed along with the anomaly matching. An exotic phase with unbroken center symmetry of chiral group has a characteristic featu

Christopher Birchall, Henning Schomerus

We consider the transport of electrons passing through a mesoscopic device possessing internal dynamical quantum degrees of freedom. The mutual interaction between the system and the conduction electrons contributes to the current fluctuations, which we describe in terms of full counting statistics. We identify conditions where this discriminates coherent fr

Armel Andami Ovono

In this paper we study the asymptotic behaviour of a nonlocal nonlinear parabolic equation governed by a parameter. After giving the existence of unique branch of solutions composed by stable solutions in stationary case, we gives for the parabolic problem $L^\infty $ estimates of solution based on using the Moser iterations and existence of global attractor