April 2013 arXiv papers — page 17

N. Upadhyaya, L. R. Gomez, V. Vitelli

Disordered packings of soft grains are fragile mechanical systems that loose rigidity upon lowering the external pressure towards zero. At zero pressure, we find that any infinitesimal strain-impulse propagates initially as a non-linear solitary wave progressively attenuated by disorder. We demonstrate that the particle fluctuations generated by the solitary

A. A. Aczel, D. E. Bugaris, J. Yeon, C. de la Cruz

We present a neutron powder diffraction study of the monoclinic double perovskite systems Nd2NaB'O6 (B' = Ru, Os), with magnetic atoms occupying both the A and B' sites. Our measurements reveal coupled spin ordering between the Nd and B' atoms with magnetic transition temperatures of 14 K for Nd2NaRuO6 and 16 K for Nd2NaOsO6. There is a Type

Behrouz Taji

In this paper we prove that for a nonsingular projective variety of dimension at most 4 and with non-negative Kodaira dimension, the Kodaira dimension of coherent subsheaves of $Ω^p$ is bounded from above by the Kodaira dimension of the variety. This implies the finiteness of the fundamental group for such an $X$ provided that $X$ has vanishing Kodaira dimen

R. Cartas-Fuentevilla

We determine the more general geometrical flow in the space of metrics corresponding to the steepest descent for the three-dimensional gravitational Chern-Simons action, extending the results previously considered in Class. Quantum Grav. 25 (2008) 165019, and reveling another trouble with the four dimensional Hořava-Lifshitz gravity introduced in Phys. Rev.

Michael H. Seymour, Marilyn Marx

Monte Carlo event generators are essential components of almost all experimental analyses and are also widely used by theorists and experiments to make predictions and preparations for future experiments. They are all too often used as "black boxes", without sufficient consideration of their component models or their reliability. In this set of three

Hesham Mansour, Nady Bakhet

The aim of this work is to search for a new heavy Higgs boson in the B-L extension of the Standard Model at LHC using the data produced from simulated collisions between two protons at different center of mass energies by Monte Carlo event generator programs to find new Higgs boson signatures at the LHC. Also we study the production and decay channels for Hi

Hari P. Paudel, Chris Stockbridge, Jerome Mertz, Thomas Bifano

We demonstrate feedback-optimized focusing of spatially coherent polychromatic light after transmission through strongly scattering media, and describe the relationship between optimized focus intensity and initial far-field speckle contrast. Optimization is performed using a MEMS spatial light modulator with camera-based or spectrometer-based feedback. We o

Charles F. Dunkl

This is an expository note on useful expressions for the density function of a product of independent random variables where each variable has a Beta distribution.

Igor Medved', Anton Trnik, Robert Cerny

The competing influence of two types of interactions on surface diffusion is investigated: one of them, epsilon, acts between adsorbed particles, while the other one, eta, between activated and adsorbed particles. To this end, a specific lattice-gas model on a triangular, square, and hexagonal lattice is considered with an attractive epsilon and an attractiv

Simone Marocchi, Paolo Ferriani, Nuala Mai Caffrey, Franca Manghi

Using first-principles calculations we demonstrate sizable exchange coupling between a magnetic molecule and a magnetic substrate via a graphene layer. As a model system we consider cobaltocene (CoCp$_2$) adsorbed on graphene deposited on Ni(111). We find that the magnetic coupling between the molecule and the substrate is antiferromagnetic and varies consid

Nicola M. Pugno

A great flourish of interest in the development of new high-strength and high-toughness materials is taking place in contemporary materials science, with the aim of surpassing the mechanical properties of commercial high-performance fibres. Recently, macroscopic buckypapers, nanotube bundles and graphene sheets have been manufactured. While their macroscopic

M. G. Kim, G. S. Tucker, D. K. Pratt, S. Ran

Inelastic neutron scattering measurements on Ba(Fe$_{0.963}$Ni$_{0.037}$)$_2$As$_2$ manifest a neutron spin resonance in the superconducting state with anisotropic dispersion within the Fe layer. Whereas the resonance is sharply peaked at Q$_{AFM}$ along the orthorhombic a axis, the resonance disperses upwards away from Q$_{AFM}$ along the b axis. In contras

Mohammad Javad Abdi

Reweighted l1-algorithms have attracted a lot of attention in the field of applied mathematics. A unified framework of such algorithms has been recently proposed by Zhao and Li. In this paper we construct a few new examples of reweighted l1-methods. These functions are certain concave approximations of the l0-norm function. We focus on the numerical comparis

Alain Audouard, Jean-Yves Fortin, David Vignolles, Rustem B. Lyubovskii

De Haas-van Alphen oscillations are studied for Fermi surfaces illustrating the Pippard's model, commonly observed in multiband organic metals. Field- and temperature-dependent amplitude of the various Fourier components, linked to frequency combinations arising from magnetic breakdown between different bands, are considered. Emphasis is put on the Onsag

André-Pierre Abellard, Danjela Kuscer, Janez Holc, Franck Levassort

We have studied the processing of piezoelectric thick films using electrophoretic deposition (EPD) for high-frequency ultrasound applications. Lead-zirconium-titanate (PZT) particles synthetized by solid states synthesis were dispersed in ethanol using ammonium polyacrylate (PAA). The electrophoretic deposition of PZT particles was performed at a constant-cu

Amandine Aftalion, Jimena Royo-Letelier

We consider the energy modeling a two component Bose-Einstein condensate in the limit of strong coupling and strong segregation. We prove the $Γ$-convergence to a perimeter minimization problem, with a weight given by the density of the condensate. In the case of equal mass for the two components, this leads to symmetry breaking for the ground state. The pro

Serge Galam

The drastic effect of local alliances in three-party competition is investigated in democratic hierarchical bottom-up voting. The results are obtained analytically using a model which extends a sociophysics frame introduced in 1986 \cite{psy} and 1990 \cite{lebo} to study two-party systems and the spontaneous formation of democratic dictatorship. It is worth

Igor Romanovsky, Constantine Yannouleas, Uzi Landman

Armchair and zigzag edge terminations in planar hexagonal and trigonal graphene nanorings are shown to underlie one-dimensional topological states associated with distinctive energy gaps and patterns (e.g., linear dispersion of the energy of an hexagonal ring with an armchair termination versus parabolic dispersion for a zigzag terminated one) in the bands o

Mohammad-Ali Miri, Matthias Heinrich, Ramy El-Ganainy, Demetrios N. Christodoulides

We show that supersymmetry can provide a versatile platform in synthesizing a new class of optical structures with desired properties and functionalities. By exploiting the intimate relationship between superpatners, one can systematically construct index potentials capable of exhibiting the same scattering and guided wave characteristics. In particular, in

F. González Canales, A. Mondragón, M. Mondragón, U. J. Saldaña Salazar

S3 models offer a low energy approach to describe the observed pattern of masses and mixing, of both quarks and leptons. In this work, we first revisit an S3 model with only one Higgs electroweak doublet, where the flavour symmetry must be broken in order to produce an acceptable pattern of masses and mixing for fermions. Then, we analyse different S3 models

Florian Lehner

A colouring of a graph G is called distinguishing if its stabiliser in Aut G is trivial. It has been conjectured that, if every automorphism of a locally finite graph moves infinitely many vertices, then there is a distinguishing 2-colouring. We study properties of random 2-colourings of locally finite graphs and show that the stabiliser of such a colouring

M. Tsantaki, S. G. Sousa, V. Zh. Adibekyan, N. C. Santos

Temperature, surface gravity, and metallicitity are basic stellar atmospheric parameters necessary to characterize a star. We aim to improve the description of the spectroscopic temperatures especially for the cooler stars where the differences with the Infrared Flux Method are higher, as presented in previous work. Our spectroscopic analysis is based on the

P. Pinilla, T. Birnstiel, M. Benisty, L. Ricci

Planets have been detected around a variety of stars, including low-mass objects, such as brown dwarfs. However, such extreme cases are challenging for planet formation models. Recent sub-millimeter observations of disks around brown dwarf measured low spectral indices of the continuum emission that suggest that dust grains grow to mm-sizes even in these ver

Patrick Hennebelle, Gilles Chabrier

The present paper extends our previous theory of the stellar initial mass function (IMF) by including the time-dependence, and by including the impact of magnetic field. The predicted mass spectra are similar to the time independent ones with slightly shallower slopes at large masses and peak locations shifted toward smaller masses by a factor of a few. Assu

Christopher M. Shappert, J. True Merrill, K. R. Brown, Jason M. Amini

We present a microfabricated surface-electrode ion trap with a pair of integrated waveguides that generate a standing microwave field resonant with the 171Yb+ hyperfine qubit. The waveguides are engineered to position the wave antinode near the center of the trap, resulting in maximum field amplitude and uniformity along the trap axis. By calibrating the rel

Lei Sun, Jie Gao, Xiaodong Yang

The concept of the broadband epsilon-near-zero meta-atom consisting of layered stacks with specified metallic filling ratio and thickness is proposed based on the Bergman spectral representation of the effective permittivity. The step-like metal-dielectric multilayer structures are designed to achieve realistic broadband epsilon-near-zero meta-atoms in optic

Valentin Bonzom, Bianca Dittrich

Spin foams are candidate state-sum models for transition amplitudes in quantum gravity. An active research subject is to identify the possible divergences of spin foam models, or alternatively to show that models are finite. We will discuss in detail the (non--occurrence of) divergences in the Barrett-Crane model, formulated as an integral of delta function

Gene F. Mazenko

There appears to be a longtime, very slowly evolving state in dense simple fluids which, for high enough density, approaches a glassy nonergodic state. The nature of the nonergodic state can be characterized by the associated static equilibrium state. In particular, systems driven by Smoluchowski or Newtonian dynamics share the same static equilibrium and no

Giovanni Mongardi

In the present paper we prove that finite symplectic groups of automorphisms of manifolds of k3^[n] type can be obtained by deforming natural morphisms arising from K3 surfaces if and only if they satisfy a certain numerical condition.

Tusheng Zhang

In this paper, we obtained the strong convergence of Wong-Zakai approximations of reflected SDEs in a general multidimensional domain giving an affirmative answer to the question posed in [ES].

Lubica Holá, László Zsilinszky

The graph topology $τ_Γ$ is the topology on the space $C(X)$ of all continuous functions defined on a Tychonoff space $X$ inherited from the Vietoris topology on $X\times \mathbb R$ after identifying continuous functions with their graphs. It is shown that all completeness properties between complete metrizability and hereditary Baireness coincide for the gr

Sohail Bahmani, Petros T. Boufounos, Bhiksha Raj

This paper studies a formulation of 1-bit Compressed Sensing (CS) problem based on the maximum likelihood estimation framework. In order to solve the problem we apply the recently proposed Gradient Support Pursuit algorithm, with a minor modification. Assuming the proposed objective function has a Stable Restricted Hessian, the algorithm is shown to accurate

Makarius Wenzel

Isabelle/PIDE is the current Prover IDE technology for Isabelle. It has been developed in ML and Scala in the past 4-5 years for this particular proof assistant, but with an open mind towards other systems. PIDE is based on an asynchronous document model, where the prover receives edits continuously and updates its internal state accordingly. The interpretat

Sergey Sukhov, Kyle M. Douglass, Aristide Dogariu

We demonstrate that a non-vanishing interaction force exists between pairs of induced dipoles in random, statistically stationary electromagnetic field. This new type of optical binding force leads to long-range interaction between dipolar particles even when placed in spatially incoherent fields. We also discuss several unique features of dipole-dipole inte

Titus Sandu, George Boldeiu, Victor Moagar-Poladian

The capacitance of arbitrarily shaped objects is reformulated in terms of the Neumann-Poincaré operator. Capacitance is simply the dielectric permittivity of the surrounding medium multiplied by the area of the object and divided by the squared norm of the Neumann-Poincaré eigenfunction that corresponds to its largest eigenvalue. The norm of this eigenfuncti

Flora S. Bacelar, Justin M. Calabrese, Emílio Hernández-García

Savannas are characterized by a discontinuous tree layer superimposed on a continuous layer of grass. Identifying the mechanisms that facilitate this tree-grass coexistence has remained a persistent challenge in ecology and is known as the "savanna problem". In this work, we propose a model that combines a previous savanna model (Calabrese et al., 20

Harpreet Dhanoa, Jonathan M. C. Rawlings

We have carried out an investigation of the chemical evolution of gas in different carbon-rich circumstellar environments. Previous studies have tended to invoke terrestrial flame chemistries, based on acetylene (C2H2) combustion to model the formation of carbon dust, via Polycyclic Aromatic Hydrocarbons (PAHs). In this work we pay careful attention to the a

Alexander Getmanenko

In the context of complex WKB analysis, we discuss a one-dimensional Schrödinger equation $ -h^2\partial_x^2 f(x,h) + [Q(x)+hQ_1(x,h)]f(x,h) =0, \ \ \ h\to 0, $ where $Q(x)$, $Q_1(x,h)$ are analytic near the origin $x=0$, $Q(0)=0$, and $Q_1(x,h)$ is a factorially divergent power series in $h$. We show that there is a change of independent variable $y=y(x,h)$

Emmy Murphy

For a certain class of exotic contact manifolds of dimension greater than 3, we show that there is an abundance of closed exact Lagrangians in their symplectization. All of these Lagrangians are displaceable by Hamiltonian isotopy, and many of the examples are nulhomotopic.

Margarita Lesik, Piernicola Spinicelli, Sébastien Pezzagna, Patrick Happel

The creation of nitrogen-vacancy centres in diamond is nowadays well controlled using nitrogen implantation and annealing. Although the high-resolution placement of NV centres has been demonstrated using either collimation through pierced AFM tips or masks with apertures made by electron beam lithography, a targeted implantation into pre-defined structures i

Saeed Abdallah, Ioannis N. Psaromiligkos

We propose an expectation maximization (EM)-based algorithm for semi-blind channel estimation of reciprocal channels in amplify-and-forward (AF) two-way relay networks (TWRNs). By incorporating both data samples and pilots into the estimation, the proposed algorithm provides substantially higher accuracy than the conventional training-based approach. Further

Stefano Cavuoti

In the last decade a new generation of telescopes and sensors has allowed the production of a very large amount of data and astronomy has become, a data-rich science; this transition is often labeled as: "data revolution" and "data tsunami". The first locution puts emphasis on the expectations of the astronomers while the second stresses, ins

Yi Fang, Kai-Kit Wong, Lin Wang, Kin-Fai Tong

In this paper, we investigate the error performance of the protograph (LDPC) codes over Nakagami-$m$ fading relay channels. We first calculate the decoding thresholds of the protograph codes over such channels with different fading depths (i.e., different values of $m$) by exploiting the modified protograph extrinsic information transfer (PEXIT) algorithm. F

Filippo Bracci, Mark Elin, David Shoikhet

In this paper we introduce a class of pseudo-dissipative holomorphic maps which contains, in particular, the class of infinitesimal generators of semigroups of holomorphic maps on the unit ball of a complex Banach space. We give a growth estimate for maps of this class. In particular, it follows that pseudo-dissipative maps on the unit ball of (infinite-dime

Jolanta Sztuk-Dambietz, Steffen Hauf, Andreas Koch, Markus Kuster

The European X-ray Free Electron Laser (XFEL.EU) will provide as-yet-unrivaled peak brilliance and ultra-short pulses of spatially coherent X-rays with a pulse length of less than 100 fs in the energy range between 0.25 and 25 keV. The high radiation intensity and ultra-short pulse duration will open a window for novel scientific techniques and will allow to

A. V. Poshakinskiy, S. A. Tarasenko

We develop the microscopic theory of electron spin dephasing in (110)-grown quantum wells where the electron scattering time is comparable to or exceeds the period of spin precession in the effective magnetic field caused by spin-orbit coupling. Structures with homogeneous and fluctuating Rashba field, which triggers the dephasing of electron spins aligned a

E. Victoria Dydek, Martin Z. Bazant

The conductivity of highly charged membranes is nearly constant, due to counter-ions screening pore surfaces. Weakly charged porous media, or "leaky membranes", also contain a significant concentration of co-ions, whose depletion at high current leads to ion concentration polarization and conductivity shock waves. To describe these nonlinear phenomen

Masahiro Yukawa, Shun-ichi Amari

The least squares problem is formulated in terms of Lp quasi-norm regularization (0<p<1). Two formulations are considered: (i) an Lp-constrained optimization and (ii) an Lp-penalized (unconstrained) optimization. Due to the nonconvexity of the Lp quasi-norm, the solution paths of the regularized least squares problem are not ensured to be continuous. A criti

Peter Rickhaus, Romain Maurand, Ming-Hao Liu, Markus Weiss

Graphene is a 2-dimensional (2D) carbon allotrope with the atoms arranged in a honeycomb lattice. The low-energy electronic excitations in this 2D crystal are described by massless Dirac fermions that have a linear dispersion relation similar to photons. Taking advantage of this optics-like electron dynamics, generic optical elements like lenses, beam splitt

Claire Mathieu, Hang Zhou

We study the problem of reconstructing a hidden graph given access to a distance oracle. We design randomized algorithms for the following problems: reconstruction of a degree bounded graph with query complexity $\tilde{O}(n^{3/2})$; reconstruction of a degree bounded outerplanar graph with query complexity $\tilde{O}(n)$; and near-optimal approximate recons

Matias Urdampilleta, Svetlana Klyatskaya, Mario Ruben, Wolfgang Wernsdorfer

A multi-terminal device based on a carbon nanotube quantum dot was used at very low tem- perature to probe a single electronic and nuclear spin embedded in a bis-phthalocyanine Terbium (III) complex (TbPc2). A spin-valve signature with large conductance jumps was found when two molecules were strongly coupled to the nanotube. The application of a transverse

Claude Castelluccia, Abdelberi Chaabane, Markus Dürmuth, Daniele Perito

Passwords are widely used for user authentication and, despite their weaknesses, will likely remain in use in the foreseeable future. Human-generated passwords typically have a rich structure, which makes them susceptible to guessing attacks. In this paper, we study the effectiveness of guessing attacks based on Markov models. Our contributions are two-fold.

M. Grünewald, R. Göckeritz, N. Homonnay, F. Würthner

We report the results of magnetoresistance measurements in vertical organic spin valves with the magnetic field oriented perpendicular to the layer stack. The magnetoresistance measurements were performed after carefully preparing either parallel or antiparallel in-plane magnetization states of the magnetic electrodes in order to observe traces of Hanle prec

Guillaume Bossard, Stefanos Katmadas

We present a manifestly duality covariant formulation of the composite non-BPS and almost-BPS systems of multi-centre black hole solutions in four dimensions. The method of nilpotent orbits is used to define the two systems in terms of first order flow equations that transform covariantly under the duality group. Subsequently, we rewrite both systems of equa

Stefan Buhrandt, Lars Fritz

Chiral magnets, such as MnSi, display a rich finite temperature phase diagram in an applied magnetic field. The most unusual of the phases encountered is the so called A-phase characterized by a triangular lattice of skyrmion tubes. Its existence cannot be captured within a mean-field treatment of a Landau-Ginzburg functional but thermal fluctuations to Gaus

Fabio Deon, Sandra Šopić, Alberto F. Morpurgo

We have investigated transport through graphene Andreev interferometers exhibiting reentrance of the superconducting proximity effect. We observed a crossover in the Andreev conductance oscillations as a function of gate voltage ($V_{BG}$). At high $V_{BG}$ the energy-dependent oscillation amplitude exhibits a scaling predicted for non-interacting electrons,

K. K. Kampoukos, S. K. Mercourakis

Using a strengthening of the concept of $\K$ set, introduced in this paper, we study a certain subclass of the class of $\K$ Banach spaces; the so called strongly $\K$ Banach spaces. This class of spaces includes subspaces of strongly weakly compactly generated (SWCG) as well as Polish Banach spaces and it is related to strongly weakly $\mathcal{K}$--analyti

B. Hanmanthu, B. Raghu Ram, P. Niranjan

Privacy is become major issue in distributed data mining. In the literature we can found many proposals of privacy preserving which can be divided into two major categories that is trusted third party and multiparty based privacy protocols. In case of trusted third party models the conventional asymmetric cryptographic based techniques will be used and in ca

Maggie Habeeb, Delaram Kahrobaei, Charalambos Koupparis, Vladimir Shpilrain

In this paper, we describe a brand new key exchange protocol based on a semidirect product of (semi)groups (more specifically, on extension of a (semi)group by automorphisms), and then focus on practical instances of this general idea. Our protocol can be based on any group, in particular on any non-commutative group. One of its special cases is the standard

Hodjat Pendar, Thierry Platini, Rahul V. Kulkarni

Stochasticity in gene expression gives rise to fluctuations in protein levels across a population of genetically identical cells. Such fluctuations can lead to phenotypic variation in clonal populations, hence there is considerable interest in quantifying noise in gene expression using stochastic models. However, obtaining exact analytical results for protei

Ferenc Glück, Guido Drexlin, Benjamin Leiber, Susanne Mertens

The KATRIN experiment is designed to determine the absolute neutrino mass scale with a sensitivity of 200 meV (90 % CL) by measuring the electron energy spectrum close to the endpoint of molecular tritium beta decay. Electrons from a high-intensity gaseous tritium source are guided by a strong magnetic field of a few T to the analyzing plane of the main spec

Ashwin J., Oleg Gendelman, Itamar Procaccia, Carmel Shor

It is well known experimentally that well-quenched amorphous solids exhibit a plastic instability in the form of a catastrophic shear localization at a well defined value of the external strain. The instability may develop to a shear-band that in some cases is followed by a fracture. It is also known that the values of the yield-strain (and yield-stress), as

S. Plumari, V. Greco, L. P. Csernai

We employ a relativistic transport theory to describe the fireball expansion of the matter created in ultra-relativistic heavy-ion collisions (uRHICs). Developing an approach to fix locally the shear viscosity to entropy density $η/s$, we study the impact of a temperature dependent $η/s(T)$ on the build-up of the elliptic flow, $v_2$, a measure of the angula

Peter Borg

If $a_1, a_2, ..., a_k$ and $n$ are positive integers such that $n = a_1 + a_2 + ... + a_k$, then the sum $a_1 + a_2 + ... + a_k$ is said to be a \emph{partition of $n$} of \emph{length $k$}, and $a_1, a_2, ..., a_k$ are said to be the \emph{parts} of the partition. Two partitions that differ only in the order of their parts are considered to be the same. We

Janusz Mierczyński

We present a simple proof of monotonicity for cooperative systems of linear ordinary differential equations, without having recourse to approximation by strongly cooperative systems.

Haizhong Li, Yong Wei, Changwei Xiong

In this paper, we prove a positive mass theorem and Penrose-type inequality of the Gauss-Bonnet-Chern mass $m_2$ for the graphic manifold with flat normal bundle.

E. J. Salumbides, J. C. J. Koelemeij, J. Komasa, K. Pachucki

Highly accurate results from frequency measurements on neutral hydrogen molecules H_2, HD and D_2 as well as the HD^+ ion can be interpreted in terms of constraints on possible fifth-force interactions. Where the hydrogen atom is a probe for yet unknown lepton-hadron interactions, and the helium atom is sensitive for lepton-lepton interactions, molecules ope

Edgar M. Blokhuis, Alan E. van Giessen

It is argued that to arrive at a quantitative description of the surface tension of a liquid drop as a function of its inverse radius, it is necessary to include the bending rigidity k and Gaussian rigidity k_bar in its description. New formulas for k and k_bar in the context of density functional theory with a non-local, integral expression for the interact

Alex Taekyung Lee, Myung Joon Han

Using first-principles density functional theory calculations, we investigated the electronic structure and magnetic properties of (LaMnO$_3$)$_m$/(LaNiO$_3$)$_n$ superlattices stacked along (001)-direction. The electrons are transferred from Mn to Ni, and the magnetic moments are induced at Ni sites that are paramagnetic in bulk and other types of superlatt

Bowen Yan, Steve Gregory

Sampling techniques such as Respondent-Driven Sampling (RDS) are widely used in epidemiology to sample &#34;hidden&#34; populations, such that properties of the network can be deduced from the sample. We consider how similar techniques can be designed that allow the discovery of the structure, especially the community structure, of networks. Our method invol

Manuel Delgado, Pedro A. Garcia-Sanchez, José C. Rosales

We propose a list of open problems in numerical semigroups.

V. Gasparian, Zh. S. Gevorkian

The Faraday rotation angle is calculated in a diffusive regime in a three dimensional disordered slab. It is shown that it is an oscillating function of the magnetic field or the mediums internal properties, and is proportional to the ratio of the inelastic mean free path to the mean free path, that is to the average number of photon scatterings. The maximum

Si-xue Qin, Dirk H. Rischke

The maximum entropy method is used to compute the quark spectral function at nonzero temperature. We solve the gap equation of quantum chromodynamics (QCD) self-consistently, employing a rainbow kernel which phenomenologically models results from Dyson-Schwinger equations (DSE) and lattice QCD. We use the criterion of positivity restoration of the spectral f

C. J. Cotter, D. D. Holm

We derive a family of ideal (nondissipative) 3D sound-proof fluid models that includes both the Lipps-Hemler anelastic approximation (AA) and the Durran pseudo-incompressible approximation (PIA). This family of models arises in the Euler-Poincaré framework involving a constrained Hamilton&#39;s principle expressed in the Eulerian fluid description. The deriv

Matias Urdampilleta, Svetlana Klyatskaya, Jean-Pierre Cleuziou, Mario Ruben

Magnetic molecules possess a high potential as building blocks for the design of spintronic devices. Moreover, the use of molecular materials opens the way for the controlled use of bottom-up, e.g. supramolecular, processing techniques combining massively parallel self-fabrication with conventional top-down nanostructuring techniques. The development of soli

Natsuki Watanabe

The gravitational impact inside and outside of a domain wall is studied in the context of $f(R)$ gravity theory. The function $f(R)$ is found which satisfies the stability conditions. Our results imply that the domain wall may cause topological inflation.

U. Gran, J. Gutowski, G. Papadopoulos

We solve the Killing spinor equations for all near-horizon IIB geometries which preserve at least one supersymmetry. We show that generic horizon sections are 8-dimensional almost Hermitian spin${}_c$ manifolds. Special cases include horizon sections with a $Spin(7)$ structure and those for which the Killing spinor is pure. We also explain how the common sec

Jean-Christophe Novelli, Lenny Tevlin, Jean-Yves Thibon

We investigate the connections between various noncommutative analogues of Hall-Littlewood and Macdonald polynomials, and define some new families of noncommutative symmetric functions depending on two sequences of parameters.

Shota Gugushvili, Peter Spreij

We establish posterior consistency for non-parametric Bayesian estimation of the dispersion coefficient of a time-inhomogeneous Brownian motion.

Jan L. Cieśliński

Locally exact integrators preserve linearization of the original system at every point. We construct energy-preserving locally exact discrete gradient schemes for arbitrary multidimensional canonical Hamiltonian systems by modifying classical discrete gradient schemes. Modifications of this kind are found for any discrete gradient.

Lieven Le Bruyn

Lecture notes of a course on A. Smirnov&#39;s approach to the ABC-conjecture via F1-geometry and an attempt to relate this to Jim Borger&#39;s F1-geometry based on lambda-rings.

Goce Chadzitaskos

We present a proposal of a new type of telescopes using a rotating parabolic strip as the primary mirror. It is the most principal modification of the design of telescopes from the times of Galileo and Newton. In order to demonstrate the basic idea, the image of an artificial constellation observed by this kind of telescope was reconstructed using the techni

Maxime Hauray, Claude Le Bris

We provide in this article a new proof of the uniqueness of the flow solution to ordinary differential equations with $BV$ vector-fields that have divergence in $L^\infty$ (or in $L^1$) and that are nearly incompressible (see the text for the definition of this term). The novelty of the proof lies in the fact it does not use the associated transport equation

D. Kamenskyi, H. Engelkamp, T. Fischer, M. Uhlarz

We report on an investigation of optical properties of multiferroic CoCr$_{2}$O$_{4}$ at terahertz frequencies in magnetic fields up to 30 T. Below the ferrimagnetic transition (94 K), the terahertz response of CoCr$_{2}$O$_{4}$ is dominated by a magnon mode, which shows a steep magnetic-field dependence. We ascribe this mode to an exchange resonance between

H Ahmed, ME Dieckmann, L Romagnani, D Doria

We report on the temporally and spatially resolved detection of the precursory stages that lead to the formation of an unmagnetized, supercritical collision-less shock in a laser-driven laboratory experiment. The measured evolution of the electrostatic potential associated with the shock unveils the transition from a current free double layer into a symmetri

ME Dieckmann, H Ahmed, G Sarri, D Doria

Nonrelativistic electrostatic unmagnetized shocks are frequently observed in laboratory plasmas and they are likely to exist in astrophysical plasmas. Their maximum speed, expressed in units of the ion acoustic speed far upstream of the shock, depends only on the electron-to-ion temperature ratio if binary collisions are absent. The formation and evolution o

Charles L. Majer, Sven Meyer, Sara Konrad, Eleonora Sarli

This paper continues a series in which we intend to show how all observables of galaxy clusters can be combined to recover the two-dimensional, projected gravitational potential of individual clusters. Our goal is to develop a non-parametric algorithm for joint cluster reconstruction taking all cluster observables into account. In this paper, we begin with t

Raphael Hauser, Heinrich Matzinger

Considering two optimally aligned random sequences, we investigate the effect on the alignment score caused by changing a random letter in one of the two sequences. Using this idea in conjunction with large deviations theory, we show that in alignments with a low proportion of gaps the optimal alignment is locally unique in most places with high probability.

Judith Ngoumou, Thomas Preibisch, Thorsten Ratzka, Andreas Burkert

Optical and near-infrared images of the Carina Nebula show a peculiar arc-shaped feature, which we call the &#34;Sickle&#34;, next to the B-type star Trumpler 14 MJ 218. We use multi-wavelength observations to explore and constrain the nature and origin of the nebulosity. Using sub-mm data from APEX/LABOCA as well as Herschel far-infrared maps, we discovered

Sergei V. Bulanov, Timur Zh. Esirkepov, Masaki Kando, James K. Koga

We discuss the key important regimes of electromagnetic field interaction with charged particles. Main attention is paid to the nonlinear Thomson/Compton scattering regime with the radiation friction and quantum electrodynamics effects taken into account. This process opens a channel of high efficiency electromagnetic energy conversion into hard electromagne

M. Boulagouaz, A. Leroy

In this paper we introduce the notion of cyclic ($f(t),σ,δ$)-codes for $f(t)\in \Ore$. These codes generalize the $θ$-codes as introduced by D. Boucher, F. Ulmer, W. Geiselmann \cite{BGU}. We construct generic and control matrices for these codes. As a particular case the ($\si,\de$)-$W$-code associated to a Wedderburn polynomial are defined and we show that

Andrew T. Barker

We explore an approach due to Nievergelt of decomposing a time-evolution equation along the time dimension and solving it in parallel with as little communication as possible between the processors. This method computes a map from initial conditions to final conditions locally on slices of the time domain, and then patches these operators together into a glo

Christian Klein, Kristelle Roidot

The formation of singularities in solutions to the dispersionless Kadomtsev-Petviashvili (dKP) equation is studied numerically for different classes of initial data. The asymptotic behavior of the Fourier coefficients is used to quantitatively identify the critical time and location and the type of the singularity. The approach is first tested in detail in 1

R. N. Bhowmik, N. Naresh, B. Ghosh, S. Banerjee

The compound alpha-Fe1.4Ga0.6O3 has been prepared by mechanical alloying of alpha-Fe2O3 and Ga2O3 and subsequent heating of the mechanical alloyed samples in vacuum condition. Magnetic ordering of alpha-Fe2O3 has been modified by substitution of non-magnetic Ga atoms. The ferromagnetism in alpha-Fe1.4Ga0.6O3 is more soft and enhanced in comparison to alpha-F

David R. Wood

Hadwiger&#39;s Conjecture states that every $K_{t+1}$-minor-free graph is $t$-colourable. It is widely considered to be one of the most important conjectures in graph theory. If every $K_{t+1}$-minor-free graph has minimum degree at most $δ$, then every $K_{t+1}$-minor-free graph is $(δ+1)$-colourable by a minimum-degree-greedy algorithm. The purpose of this

Michel Destrade

The propagation of surface (Rayleigh) waves over a rotating orthorhombic crystal is studied. The crystal possesses three crystallographic axes, normal to the symmetry planes: the half-space is cut along a plane normal to one of these axes, the wave travels in the direction of another, and the rotation occurs at a uniform rate about any of the three axes. The

Oualid El Halimi, Peyman Derafshkavian, Abdulrhman Albeladi, Faisal Alrashdi

This document gathers high-level users requirements and describes the system features. It provides a detailed explanation of the main functionalities of the system with a more emphasis on the stakeholders needs and wants. Indeed, the document goes through design constraints that may restrict various aspects of the design and implementation.

Felix Schmitt, Ralf Heidger, Stephen Straub, Benjamin Weiß

SESAR is supposed to boost the development of new operational procedures together with the supporting systems in order to modernize the pan-European air traffic management (ATM). One consequence of this development is that more and more information is presented to - and has to be processed by - air traffic control officers (ATCOs). Thus, there is a strong ne

Evmorfia N. Argyriou, Aikaterini A. Sotiraki, Antonios Symvonis

Occupational fraud affects many companies worldwide causing them economic loss and liability issues towards their customers and other involved entities. Detecting internal fraud in a company requires significant effort and, unfortunately cannot be entirely prevented. The internal auditors have to process a huge amount of data produced by diverse systems, whi

M. Ndong, M. Lapert, C. Koch, D. Sugny

We apply two different monotonically convergent optimization algorithms to the control of molecular rotational dynamics by laser pulses. This example represents a quantum control problem where the interaction of the system with the external field is non-linear. We test the validity and accuracy of the two methods on the key control targets of producing molec