May 2010 arXiv papers — page 56

C. Favard, J. Ehrig, J. Wenger, P. -F. Lenne

For more than ten years now, many efforts have been done to identify and characterize nature of obstructed diffusion in model and cellular lipid membranes. Amongst all the techniques developed for this purpose, FCS, by means of determination of FCS diffusion laws, has been shown to be a very efficient approach. In this paper, FCS diffusion laws are used to p

A. Tillich, N. Przybilla, R. -D. Scholz, U. Heber

Blue straggler, which are stars that appear to be younger than they should be, are an important population of unusual stars in both stellar clusters and the halo field of the Galaxy. Most formation scenarios evoke either stellar collisions or binary stars that transfer mass or merge. We investigate high-velocity stars in the Galactic halo and perform a spect

P. M. Krstajic, E. Rezasoltani, P. Vasilopoulos

We study electron transport through waveguides (WGs) in which the strengths of the Rashba ($α$) and Dresselhaus ($β$) terms of the spin-orbit interaction (SOI) vary in space. Subband mixing, due to lateral confinement, is taken into account only between the two first subbands. For sufficiently narrow WGs the transmission $T$ exhibits a square-like shape as a

Sergei Matveev, Vladimir Turaev

We establish an existence and uniqueness theorem for prime decompositions of theta-curves in $3$-manifolds.

Paolo Lipparini

The statement in the title solves a problem raised by T. Retta. We also present a variation of the result in terms of $[ μ,κ]$-compactness.

Malgorzata Worek

A report on the recent next-to-leading order QCD calculations to t anti-t b anti-b and t anti-t + 2j processes at the CERN Large Hardon Collider is presented. Results for integrated and differential cross sections are given. A significant reduction of the scale dependence is observed in both cases, which indicates that the perturbative expansion is well unde

Martin Hoffmann, Miriam Siebenbuerger, Ludger Harnau, Markus Hund

We fabricated thermoresponsive colloidal molecules of ca. 250 nm size. Electron- and scanning force microscopy reveal the dumbbell-shaped morphology. The temperature dependence of the size and aspect ratio (ca. 1.4 to 1.6) is analyzed by depolarized dynamic light scattering and found to be in good agreement with microscopic evidence.

Denis Lacroix, Guillaume Hupin

In this work, a new functional is introduced to treat pairing correlations in finite many-body systems. Guided by the projected BCS framework, the energy is written as a functional of occupation numbers. It is shown to generalize the BCS approach and to provide an alternative to Variation After Projection framework. Illustrations of the new approach are give

Qin Liu, Tianxing Ma

Following the recent theoretical proposal and experiment on quantum spin Hall effect in HgTe/CdTe quantum wells, we consider a single magnetic impurity localized in the bulk of the system, which we treat as a classical spin. It is shown that there are always localized excited states in the bulk energy gap for arbitrarily strong impurity strength in inverted

Marianne Chapouly, Mazyar Mirrahimi

In this paper, we consider a wave equation on a bounded interval where the initial conditions are known (are zero) and we are rather interested in identifying an unknown source term $q(x)$ thanks to the measurement output $y$ which is the Neumann derivative on one of the boundaries. We use a back-and-forth iterative procedure and construct well-chosen observ

J. -M. Grießmeier, M. Khodachenko, H. Lammer, J. L. Grenfell

Stellar activity has a particularly strong influence on planets at small orbital distances, such as close-in exoplanets. For such planets, we present two extreme cases of stellar variability, namely stellar coronal mass ejections and stellar wind, which both result in the planetary environment being variable on a timescale of billions of years. For both case

P. Chaudhary, M. Brusa, G. Hasinger, A. Merloni

Our analysis is aimed at characterizing the properties of the integrated spectrum of active galactic nuclei (AGNs) such as the ubiquity of the Fe Kα emission in AGNs and the dependence of the spectral parameters on the X-ray luminosity and redshift. We selected 2646 point sources from the 2XMM catalogue at high galactic latitude (|BII| > 25 degrees) and with

Michiel de Bondt, Stefan Maubach

In this paper, we give two algorithms to compute preimages of curves under polynomial endomorphisms. In particular, this gives an efficient way of computing preimages of points. Furthermore, we explain the abstract setting under which one can iteratively compute the inverse of a polynomial automorphism.

Tomohiro Takahashi, Jiro Soda

Classically, black Holes have the rigid event horizon. However, quantum mechanically, the event horizon of black holes becomes fuzzy due to quantum fluctuations. We study Hawking radiation of a real scalar field from a fluctuating black hole. To quantize metric perturbations, we derive the quadratic action for those in the black hole background. Then, we cal

Pavel Chadima, Petr Harmanec, Stephenson Yang, Phillip D. Bennett

We collected rich series of RV measurements covering last 110 years and photometric observations from the past 6 primary eclipses, complemented them by our new observations and derived a new precise ephemeris and an orbital solution of epsilon Aur.

Michael Genkin, Eva Lindroth

In a recent paper (Phys. Rev. B {\bf 78}, 075316 (2008)), Sajeev and Moiseyev demonstrated that the bound-to-resonant transitions and lifetimes of autoionizing states in spherical quantum dots can be controlled by varying the confinment strength. In the present paper, we report that such control can in some cases be compromised by the presence of Coulomb imp

L. Roca, E. Oset

In a previous work regarding the interaction of two $ρ(770)$ resonances, the $f_2(1270)$ ($J^{PC}=2^{++}$) resonance was obtained dynamically as a two-$ρ$ molecule with a very strong binding energy, 135~MeV per $ρ$ particle. In the present work we use the $ρρ$ interaction in spin 2 and isospin 0 channel to show that the resonances $ρ_3(1690)$ ($3^{--}$), $f_

D. Moretti, D. Felinto, J. W. R. Tabosa, A. Lezama

We investigate the evolution of a Zeeman coherence grating induced in a cold atomic cesium sample in the presence of an external magnetic field. The gratings are created in a three-beam light storage configuration using two quasi-collinear writing laser pulses and reading with a counterpropagating pulse after a variable time delay. The phase conjugated pulse

Yuqin Yao, Yunbo Zeng

Based on the Kupershmidt deformation for any integrable bi-Hamiltonian systems presented in [4], we propose the generalized Kupershmidt deformation to construct new systems from integrable bi-Hamiltonian systems, which provides a nonholonomic perturbation of the bi-Hamiltonian systems. The generalized Kupershmidt deformation is conjectured to preserve integr

Aslak Bakke Buan, Idun Reiten, Hugh Thomas

For a finite dimensional hereditary algebra, we consider: exceptional sequences in the category of finite dimensional modules, silting objects in the bounded derived category, and m-cluster tilting objects in the m-cluster category. There are mutation operations on both the set of m-cluster tilting objects and the set of exceptional sequences. It is also pos

E. A. Laird, J. M. Taylor, D. P. DiVincenzo, C. M. Marcus

Initialization, manipulation, and measurement of a three-spin qubit are demonstrated using a few-electron triple quantum dot, where all operations can be driven by tuning the nearest-neighbor exchange interaction. Multiplexed reflectometry, applied to two nearby charge sensors, allows for qubit readout. Decoherence is found to be consistent with predictions

Viacheslav Burenkov, Bing Qi, Ben Fortescue, Hoi-Kwong Lo

The security of a high speed quantum key distribution system with finite detector dead time τ is analyzed. When the transmission rate becomes higher than the maximum count rate of the individual detectors (1/τ), security issues affect the algorithm for sifting bits. Analytical calculations and numerical simulations of the Bennett-Brassard BB84 protocol are p

J. Ebrero, S. Mateos, G. C. Stewart, F. J. Carrera

We present the angular correlation function of the X-ray population of 1063 XMM-Newton observations at high Galactic latitudes, comprising up to ~30000 sources over a sky area of ~125 sq. degrees in the energy bands: soft (0.5-2 keV) and hard (2-10 keV). This is the largest sample of serendipitous X-ray sources ever used for clustering analysis purposes to d

Arttu Rajantie, Anders Tranberg

We study how topological defects manifest themselves in the equal-time two-point field correlator. We consider a scalar field with Z_2 symmetry in 1, 2 and 3 spatial dimensions, allowing for kinks, domain lines and domain walls, respectively. Using numerical lattice simulations, we find that in any number of dimensions, the correlator in momentum space is to

Andri Mirzal, Masashi Furukawa

We describe a clustering method for labeled link network (semantic graph) that can be used to group important nodes (highly connected nodes) with their relevant link's labels by using PARAFAC tensor decomposition. In this kind of network, the adjacency matrix can not be used to fully describe all information about the network structure. We have to expand

Qiyu Sun

In this paper, it is proved that every $s$-sparse vector ${\bf x}\in {\mathbb R}^n$ can be exactly recovered from the measurement vector ${\bf z}={\bf A} {\bf x}\in {\mathbb R}^m$ via some $\ell^q$-minimization with $0< q\le 1$, as soon as each $s$-sparse vector ${\bf x}\in {\mathbb R}^n$ is uniquely determined by the measurement ${\bf z}$.

Antonio M. Garcia-Garcia, Emilio Cuevas

The propagation of waves in highly inhomogeneous media is a problem of interest in multiple fields including seismology, acoustics and electromagnetism. It is also relevant for technological applications such as the design of sound absorbing materials or the fabrication of optically devices for multi-wavelength operation. A paradigmatic example of a highly i

D. Errandonea, Ravhi S. Kumar, F. J. Manjon, V. V. Ursaki

Room temperature angle-dispersive x-ray diffraction measurements on spinel ZnGa2O4 up to 56 GPa show evidence of two structural phase transformations. At 31.2 GPa, ZnGa2O4 undergoes a transition from the cubic spinel structure to a tetragonal spinel structure similar to that of ZnMn2O4. At 55 GPa, a second transition to the orthorhombic marokite structure (C

Lorenzo Zaninetti

It is shown that the Hubble constant can be derived from the standard luminosity function of galaxies as well as from a new luminosity function as deduced from the mass-luminosity relationship for galaxies. An analytical expression for the Hubble constant can be found from the maximum number of galaxies (in a given solid angle and flux) as a function of the

J. Ruiz-Fuertes, D. Errandonea, R. Lacomba-Perales, A. Segura

We study the effects of pressure on the structural, vibrational, and magnetic behavior of cuproscheelite. We performed powder x-ray diffraction and Raman spectroscopy experiments up to 27 GPa as well as ab initio total-energy and lattice-dynamics calculations. Experiments provide evidence that a structural phase transition takes place at 10 GPa from the low-

D. Dimitrov, D. Kjurkchieva

CCD photometric observations in VRI colors and spectroscopic observations of the newly discovered eclipsing binary GSC 2314-0530 (NSVS 6550671) with dMe components and very short period of P=0.192636 days are presented. The simultaneous light-curve solution and radial velocity solution allows to determine the global parameters of GSC 2314-0530: T_{1}=3735 K;

G. Valori, B. Kliem, T. Török, V. S. Titov

We examine the nonlinear magnetofrictional extrapolation scheme using the solar active region model by Titov and Démoulin as test field. This model consists of an arched, line-tied current channel held in force-free equilibrium by the potential field of a bipolar flux distribution in the bottom boundary. A modified version, having a parabolic current density

Nuno R. O. Bastos, Rui A. C. Ferreira, Delfim F. M. Torres

We introduce a discrete-time fractional calculus of variations on the time scale $h\mathbb{Z}$, $h > 0$. First and second order necessary optimality conditions are established. Examples illustrating the use of the new Euler-Lagrange and Legendre type conditions are given. They show that solutions to the considered fractional problems become the classical dis

Evgeny A. Poletsky, Ragnar Sigurdsson

In this paper we solve the Dirichlet problems for different classes of plurisubharmonic functions on compact sets in $\mathbb C^n$ including continuous, pluriharmonic and maximal functions.

D. Kovtonyuk, V. Ryazanov

It is established a series of criteria for continuous and homeomorphic extension to the boundary of the so-called lower $Q$-homeomorphisms $f$ between domains in $\overline{\Rn}=\Rn\cup\{\infty\}$, $n\geqslant2$, under integral constraints of the type $\intΦ(Q^{n-1}(x))\,dm(x)<\infty$ with a convex non-decreasing function $Φ:[0,\infty]\to[0,\infty]$. It is s

Mario Gennaro, Pier Giorgio Prada Moroni, Scilla Degl&#39;Innocenti

The stellar helium-to-metal enrichment ratio, ΔY/ΔZ, is a widely studied astrophysical quantity. However, its value is still not precisely constrained. This paper is focused on the study of the main sources of uncertainty which affect the ΔY/ΔZ derived from the analysis of the low-main sequence (MS) stars in the solar neighborhood. The possibility to infer t

Xiao Zheng, GuanHua Chen, Yan Mo, SiuKong Koo

Based on our earlier works [Phys. Rev. B 75, 195127 (2007) & J. Chem. Phys. 128, 234703 (2008)], we propose a formally exact and numerically convenient approach to simulate time-dependent quantum transport from first-principles. The proposed approach combines time-dependent density functional theory with quantum dissipation theory, and results in a useful to

Chuanqiang Chen

Thanks to the test function of Bian-Guan[2], we successfully obtain a constant rank theorem for partial convex solutions of a class partial differential equations. This is the microscopic version of the macroscopic partial convexity principle in [1], and also is a generalization of the result in [2].

Gilbert Chahine, Andriy V. Kityk, Klaus Knorr, Ronan Lefort

We report combined optical birefringence and neutron scattering measurements on the liquid crystal 12CB nanoconfined in mesoporous silicon layers. This liquid crystal exhibits strong nematic-smectic coupling responsible for a discontinuous isotropic-to-smectic phase transition in the bulk state. Confined in porous silicon, 12CB is subjected to strong anisotr

Andrea Campagna, Rasmus Pagh

Given a directed acyclic graph with labeled vertices, we consider the problem of finding the most common label sequences (&#34;traces&#34;) among all paths in the graph (of some maximum length m). Since the number of paths can be huge, we propose novel algorithms whose time complexity depends only on the size of the graph, and on the relative frequency epsil

B. Tatischeff, I. Brissaud

Relations between elementary particles masses are given using only known physical constants, without any arbitrary number.

Federica Lo Verso, Sergei A. Egorov, Andrey Milchev, Kurt Binder

A coarse grained model for flexible polymers end-grafted to repulsive spherical nanoparticles is studied for various chain lengths and grafting densities under good solvent conditions, by Molecular Dynamics methods and density functional theory. With increasing chain length the monomer density profile exhibits a crossover to the star polymer limit. The distr

F. Pace, J. -C. Waizmann, M. Bartelmann

We study the spherical collapse model for several dark energy scenarios using the fully nonlinear differential equation for the evolution of the density contrast within homogeneous spherical overdensities derived from Newtonian hydrodynamics. While mathematically equivalent to the more common approach based on the differential equation for the radius of the

Igal Talmi

Eigenvalues of eigenstates in jn configurations (n identical nucle- ons in the j -orbit) are functions of two-body energies. In some cases they are linear combinations of two-body energies whose coe+/-cients are independent of the interaction and are rational non-negative num- bers. It is shown here that a state which is an eigenstate of any two-body interac

Eli Glasner, Benjamin Weiss

Returning to a classical question in Harmonic Analysis we strengthen an old result of Walter Rudin. We show that there exists a weakly almost periodic function on the group of integers Z which is not in the norm-closure of the algebra B(Z) of Fourier-Stieltjes transforms of measures on the circle, the dual group of Z, and which is recurrent. We also show tha

I. L. Kovalenko, N. N. Kudryavtseva

It is well known that psychoemotional disorders may be accompanied by decreased sociability in humans. It has been shown that repeated social defeats in 10 daily agonistic interactions in male mice led to development of the expressed level of anxiety and to reduction of communication estimated in the elevated plus-maze and partition tests, respectively. In t

Subrata Pal

Nuclear multifragmentation in intermediate energy heavy ion collisions has long been associated with liquid-gas phase transition. We calculate the shear viscosity to entropy density ratio eta/s for an equilibrated system of nucleons and fragments produced in multifragmentation within an extended statistical multifragmentation model. The temperature dependenc

Zhi-Xi Wu, Petter Holme

We study a model of opinion formation where the collective decision of group is said to happen if the fraction of agents having the most common opinion exceeds a threshold value, a \textit{critical mass}. We find that there exists a unique, non-trivial critical mass giving the most efficient convergence to consensus. In addition, we observe that for small cr

Olivier Teste

Multidimensional databases support efficiently on-line analytical processing (OLAP). In this paper, we depict a model dedicated to multidimensional databases. The approach we present designs decisional information through a constellation of facts and dimensions. Each dimension is possibly shared between several facts and it is organised according to multiple

Badawy Abu-Ibrahim, Akihisa Kohama

We study the scaling properties of proton-nucleus total reaction cross sections for stable nuclei and propose an approximate expression in proportion to Z^{2/3}σ_{pp}^{total} + N^{2/3} σ_{pn}^{total}. Based on this expression, we can derive a relation that enables us to predict a total reaction cross section for any stable nucleus within 10% uncertainty at m

Guodong Zhou, Alexander Zimmermann

We contribute to the classification of finite dimensional algebras under stable equivalence of Morita type. More precisely we give a classification of the class of Erdmann&#39;s algebras of dihedral, semi-dihedral and quaternion type and obtain as byproduct the validity of the Auslander-Reiten conjecture for these classes of algebras.

Jean-Claude Juhel, Dominique Dufour

The object of this contribution is to present the ideas behind the thinking of the French economist Pierre-Joseph Proudhon (1809-1865) in relation to the causes and effects of Stock market speculation. It is based upon the works of this author but particularly on his &#34;Manuel du spéculateur à la Bourse&#34; (Stock Market Speculator Manual) edited in 1857

Olivier Teste

In this paper, we study the data warehouse modelling used in decision support systems. We provide an object-oriented data warehouse model allowing data warehouse description as a central repository of relevant, complex and temporal data. Our model integrates three concepts such as warehouse object, environment and warehouse class. Each warehouse object is co

Franck Ravat, Olivier Teste

This paper deals with temporal and archive object-oriented data warehouse modelling and querying. In a first step, we define a data model describing warehouses as central repositories of complex and temporal data extracted from one information source. The model is based on the concepts of warehouse object and environment. A warehouse object is composed of on

Faiza Ghozzi, Franck Ravat, Olivier Teste, Gilles Zurfluh

This paper defines a constraint-based model dedicated to multidimensional databases. The model we define represents data through a constellation of facts (subjects of analyse) associated to dimensions (axis of analyse), which are possibly shared. Each dimension is organised according to several hierarchies (views of analyse) integrating several levels of dat

Gilles Hubert, Olivier Teste

Decisional systems are based on multidimensional databases improving OLAP analyses. The paper describes a new OLAP operator named &#34;BLEND&#34; to perform multigradual analyses. The operation transforms multidimensional structures during querying in order to analyse measures according to various granularity levels, which are reorganised into a single param

Franck Ravat, Olivier Teste, Zurfluh Gilles

This paper describes an object-oriented model for designing complex and time-variant data warehouse data. The main contribution is the warehouse class concept, which extends the class concept by temporal and archive filters as well as a mapping function. Filters allow the keeping of relevant data changes whereas the mapping function defines the warehouse cla

Franck Ravat, Olivier Teste, Gilles Zurfluh

This article deals with OLAP systems based on multidimensional model. The conceptual model we provide, represents data through a constellation (multi-facts) composed of several multi-hierarchy dimensions. In this model, data are displayed through multidimensional tables. We define a query algebra handling these tables. This user oriented algebra is composed

Frédéric Bret, Olivier Teste

Nowadays, decisional systems have became a significant research topic in databases. Data warehouses and data marts are the main elements of such systems. This paper presents our decisional support system. We present graphical interfaces which help the administrator to build data warehouses and data marts. We present a data warehouse building interface based

Ehsan Azmoodeh

We consider fractional Black-Scholes market with proportional transaction costs. When transaction costs are present, one trades periodically i.e. we have the discrete trading with equidistance $n^{-1}$ between trading times. We derive a non trivial hedging error for a class of European options with convex payoff in the case when the transaction costs coeffic

Jean Clairambault, Vladimir Flores, Benoit Perthame, Melina Rapacioli

How far is neuroepithelial cell proliferation in the developing central nervous system a deterministic process? Or, to put it in a more precise way, how accurately can it be described by a deterministic mathematical model? To provide tracks to answer this question, a deterministic system of transport and diffusion partial differential equations, both physiol

Tony Lelievre, Kimiya Minoukadeh

We present convergence results for an adaptive algorithm to compute free energies, namely the adaptive biasing force (ABF) method. The free energy is the effective potential associated to a so-called reaction coordinate (RC). Computing free energy differences remains an important challenge in molecular dynamics due to the presence of meta-stable regions in t

Jean-François Biasse, Jacobson John Michael

We present improvements to the index-calculus algorithm for the computation of the ideal class group and regulator of a real quadratic field. Our improvements consist of applying the double large prime strategy, an improved structured Gaussian elimination strategy, and the use of Bernstein&#39;s batch smoothness algorithm. We achieve a significant speed-up a

Thierry Champion, Gisella Croce

In this article we study a system of eikonal equations. Our aim is to isolate the solutions which minimise the discontinuity set of the gradient.

Gisella Croce

In this article we study an elliptic problem with degenerate coercivity. We will show that the presence of some lower order terms has a regularizing effect on the solutions.

Kevin Rosenblum, Lihi Zelnik-Manor, Yonina C. Eldar

Recent work has demonstrated that using a carefully designed dictionary instead of a predefined one, can improve the sparsity in jointly representing a class of signals. This has motivated the derivation of learning methods for designing a dictionary which leads to the sparsest representation for a given set of signals. In some applications, the signals of i

Franck Ravat, Olivier Teste, Gilles Zurfluh

This paper deals with decision support systems resting on multidimensional modelling of data. Moreover, we intend to offer a set of concepts and mechanisms for personalized multidimensional database specifications. This personalization consists in associating weights to different components of a multidimensional schema. Personalization specifications are spe

Houssem Jerbi, Geneviève Pujolle, Franck Ravat, Olivier Teste

This paper deals with personalization of annotated OLAP systems. Data constellation is extended to support annotations and user preferences. Annotations reflect the decision-maker experience whereas user preferences enable users to focus on the most interesting data. User preferences allow annotated contextual recommendations helping the decision-maker durin

Gisella Croce, Bernard Dacorogna

In this article we discuss a generalized Wirtinger inequality.

Jean Heyvaerts

A kinetic equation for the collisional evolution of stable, bound, self gravitating and slowly relaxing systems is established, which is valid when the number of constituents is very large. It accounts for the detailed dynamics and self consistent dressing by collective gravitational interaction of the colliding particles, for the system&#39;s inhomogeneity

Michel Fliess, Cédric Join

Delta hedging, which plays a crucial rôle in modern financial engineering, is a tracking control design for a &#34;risk-free&#34; management. We utilize the existence of trends in financial time series (Fliess M., Join C.: A mathematical proof of the existence of trends in financial time series, Proc. Int. Conf. Systems Theory: Modelling, Analysis and Contro

Soon-Gil Jung, Nam Hoon Lee, Eun-Mi Choi, Won Nam Kang

We have fabricated high-quality FeSe1-x superconducting films with a bulk Tc of 11-12 K on different substrates, Al2O3(0001), SrTiO3(100), MgO(100), and LaAlO3(100), by using a pulsed laser deposition technique. All the films were grown at a high substrate temperature of 610 oC, and were preferentially oriented along the (101) direction, the latter being to

W. K. Park, C. R. Hunt, H. Z. Arham, Z. J. Xu

The superconducting order parameter in the iron-chalcogenide superconductor FeTe$_{0.55}$Se$_{0.45}$ ($T_\textrm{c}$ = 14.2 K) is investigated by point-contact Andreev reflection spectroscopy. The energy gap magnitude (3.8 meV at 1.70 K) and temperature dependence as extracted from the Andreev conductance spectra reveal strong-coupling superconductivity and

Nishant A. Mehta, Alexander G. Gray

We introduce two kernels that extend the mean map, which embeds probability measures in Hilbert spaces. The generative mean map kernel (GMMK) is a smooth similarity measure between probabilistic models. The latent mean map kernel (LMMK) generalizes the non-iid formulation of Hilbert space embeddings of empirical distributions in order to incorporate latent v

T. Kawaguchi, H. Uemura, T. Ohno, M. Tabuchi

The recently discovered high temperature superconductor F-doped LaFeAsO and related compounds represent a new class of superconductors with the highest transition temperature (Tc) apart from the cuprates. The studies ongoing worldwide are revealing that these Fe-based superconductors are forming a unique class of materials that are interesting from the viewp

Constantin Călin, Mircea Crâşmareanu, Marian Ioan Munteanu, Vincenzo Saltarelli

A structure on an almost contact metric manifold is defined as a generalization of well-known cases: Sasakian, quasi-Sasakian, Kenmotsu and cosymplectic. Then we consider a semi-invariant $ξ^{\bot}$-submanifold of a manifold endowed with such a structure and two topics are studied: the integrability of distributions defined by this submanifold and characteri

Zheng Gan, Helge Krueger

We study discontinuity of the Lyapunov exponent. We construct a limit-periodic Schrödinger operator, of which the Lyapunov exponent has a positive measure set of discontinuities. We also show that the limit-periodic potentials, whose Lyapunov exponent is discontinuous, are dense in the space of limit-periodic potentials.

Ya-feng He, Bao-quan Ai, Bambi Hu

Transformation between dense and sparse spirals is studied numerically based on a bistable FitzHugh-Nagumo model. It is found that the dense spiral can transform into two types of sparse spirals via a subcritical bifurcation: Positive Phase Sparse Spiral (PPSS) and Negative Phase Sparse Spiral (NPSS). The choice of the two types of sparse spirals after the t

Burra G. Sidharth

We consider two problems that have vexed physicists for several decades -- dark matter and the cosmological constant. The problem has been that the former has not been detected while the latter gives a far higher value than detected by observation. We argue that a time varying gravitational constant obviates the former problem, while the latter problem can b

MS Custódio, MW Beims

Rounding border effects at the escape point of open integrable billiards are analyzed via the escape times statistics and emission angles. The model is the rectangular billiard and the shape of the escape point is assumed to have a semicircular form. Stickiness and self-similar structures for the escape times and emission angles are generated inside &#34;bac

David J. E. Floyd, Jo Thomas-Osip, Gabriel Prieto

We present an analysis of the science image quality obtained on the twin 6.5 metre Magellan telescopes over a 1.5 year period, using images of ~10^5 stars. We find that the telescopes generally obtain significantly better image quality than the DIMM-measured seeing. This is qualitatively consistent with expectations for large telescopes, where the wavefront

George Dimitrov, Vasil Tsanov

We introduce a remarkable subset &#34;the stem&#34; of the set of positive roots of a reduced root system. The stem determines several interesting decompositions of the corresponding reductive Lie algebra. It gives also a nice simple three dimensional subalgebra and a &#34;Cayley transform&#34;. In the present paper we apply the above devices to give a compl

Cheng Zhang, Jianpeng Ma

We present an identity for an unbiased estimate of a general statistical distribution. The identity computes the distribution density from dividing a histogram sum over a local window by a correction factor from a mean-force integral, and the mean force can be evaluated as a configuration average. We show that the optimal window size is roughly the inverse o

Gregory J. Galloway, Kristen Schleich, Donald M. Witt

We use existence results for Jang&#39;s equation and marginally outer trapped surfaces (MOTSs) in 2+1 gravity to obtain nonexistence of geons in 2+1 gravity. In particular, our results show that any 2+1 initial data set, which obeys the dominant energy condition with cosmological constant Λ\geq 0 and which satisfies a mild asymptotic condition, must have tri

M. Anand, P. R. Kumar

For every Gaussian network, there exists a corresponding deterministic network called the discrete superposition network. We show that this discrete superposition network provides a near-optimal digital interface for operating a class consisting of many Gaussian networks in the sense that any code for the discrete superposition network can be naturally lifte

Simon N. Chandler-Wilde, Marko Lindner

In the first half of this text we explore the interrelationships between the abstract theory of limit operators (see e.g. the recent monographs of Rabinovich, Roch & Silbermann and Lindner) and the concepts and results of the generalised collectively compact operator theory introduced by Chandler-Wilde and Zhang. We build up to results obtained by applying t

Sylvain Golénia, Christoph Schumacher

The number of self-adjoint extensions of a symmetric operator acting on a complex Hilbert space is characterized by its deficiency indices. Given a locally finite unoriented simple tree, we prove that the deficiency indices of any discrete Schrödinger operator are either null or infinite. We also prove that almost surely, there is a tree such that all discre

Ali Alhazmi, Abdulrahman Al-Sharawi, Bing Liu, Deyvisson Oliveira

This document presents the business requirement of Unified University Inventory System (UUIS) in Technology-independent manner. All attempts have been made in using mostly business terminology and business language while describing the requirements in this document. Very minimal and commonly understood Technical terminology is used. Use case approach is used

Alexander Gorokhovsky, John Lott

We give a local formula for the index of a transverse Dirac-type operator on a compact manifold with a Riemannian foliation, under the assumption that the Molino sheaf is a sheaf of abelian Lie algebras.

Th. W. Kool, B. Bollegraaf

Numerical and analytical methods are used to investigate the calculation of the zero field splitting |2D| and g(perp) parameters in EPR for octahedrally surrounded d3 spin systems (S = 3/2) in strong and moderate axial crystal fields (|D|>=hν). Exact numerical computer calculations are compared with analytical results obtained from third-order perturbation t

Gigel Militaru

Let $R$, $S$ be two rings, $C$ an $R$-coring and ${}_{R}^C{\mathcal M}$ the category of left $C$-comodules. The category ${\bf Rep}\, ( {}_{R}^C{\mathcal M}, {}_{S}{\mathcal M} )$ of all representable functors ${}_{R}^C{\mathcal M} \to {}_{S}{\mathcal M}$ is shown to be equivalent to the opposite of the category ${}_{R}^C{\mathcal M}_S$. For $U$ an $(S,R)$-b

Tobias Micklitz, Alex Levchenko

We study the problem of energy relaxation in a one-dimensional electron system. The leading thermalization mechanism is due to three-particle collisions. We show that for the case of spinless electrons in a single channel quantum wire the corresponding collision integral can be transformed into an exactly solvable problem. The latter is known as the Schrodin

Andrei A. Malykh, Mikhail B. Sheftel

We consider a four-dimensional PDE possessing partner symmetries mainly on the example of complex Monge-Ampère equation (CMA). We use simultaneously two pairs of symmetries related by a recursion relation, which are mutually complex conjugate for CMA. For both pairs of partner symmetries, using Lie equations, we introduce explicitly group parameters as addit

A. Kohutych, R. Yevych, S. Perechinskii, V. Samulionis

The interaction between soft optic and acoustic phonons was investigated for Sn2P2(Se0.28S0.72)6 proper uniaxial ferroelectrics by Brillouin scattering and ultrasonic pulse-echo techniques. The elastic softening of hypersound velocity of transverse acoustic phonons and for both longitudinal and transverse ultrasound waves which propagate near direction of th

Daniela Paoletti, Fabio Finelli

We constrain a stochastic background of primordial magnetic field (PMF) by its contribution to the angular power spectrum of cosmic microwave background anisotropies. We parametrize such stochastic background by a power-law spectrum with index $n_B$ and by its Gaussian smoothed amplitude $B_λ$ on a comoving length $λ$. We give an approximation for the spectr

F. Vagnetti, S. Turriziani, D. Trevese, M. Antonucci

The observed relation between the X-ray radiation from AGNs, originating in the corona, and the optical/UV radiation from the disk is usually described by the anticorrelation between the UV to X-ray slope alpha_ox and the UV luminosity. Many factors can affect this relation, including: enhanced X-ray emission associated with the jets of radio-loud AGNs; X-ra

Bassem Ben Hamed, Lubomir Gavrilov, Martine Klughertz

We prove that the holonomy group at infinity of the Painleve VI equation is virtually commutative.

Yunhe Sheng

In this paper, we study representations of hom-Lie algebras. In particular, the adjoint representation and the trivial representation of hom-Lie algebras are studied in detail. Derivations, deformations, central extensions and derivation extensions of hom-Lie algebras are also studied as an application.

Rudolf Hanel, Stefan Thurner

To characterize strongly interacting statistical systems within a thermodynamical framework - complex systems in particular - it might be necessary to introduce generalized entropies, $S_g$. A series of such entropies have been proposed in the past, mainly to accommodate important empirical distribution functions to a maximum ignorance principle. Until now t

Thomas Fiedler, Arnaud Mortier

We consider a knot homotopy as a cylinder in 4-space. An ordinary triple point $p$ of the cylinder is called {\em coherent} if all three branches intersect at $p$ pairwise with the same index. A {\em triple unknotting} of a classical knot $K$ is a homotopy which connects $K$ with the trivial knot and which has as singularities only coherent triple points. We