December 2007 arXiv papers — page 5

Ji-Rong Ren, Tao Zhu, Shu-Fan Mo

In this paper, knotted objects (RS vortices) in the theory of topological phase singularity in electromagnetic field have been investigated in details. By using the $ϕ$-mapping topological current theory proposed by Prof. Duan, we rewrite the topological current form of RS vortices and use this topological current we reveal that the Hopf invariant of RS vort

Gabrijela Zaharijas

Recently there has been a growing evidence in favor of the presence of an Intermediate Mass Black Hole in the globular cluster G1, in Andromeda Galaxy. In this paper, we explore whether the adiabatic growth in the dark matter density due to the presence of a black hole could result in an observable gamma ray signal due to dark matter annihilation in this glo

Davy Dalmas, Anne Lelarge, Damien Vandembroucq

We perform fracture experiments on nanoscale phase separated glasses and measure crack surface roughness by atomic force microscopy. The ability of tuning the phase domain size by thermal treatment allows us to test thoroughly the predictions of crack font depinning models about the scaling properties of crack surface roughness. It appears that in the range

D. A. Kulikov, R. S. Tutik

The solvable quantum mechanical model for the relativistic two-body system composed of spin-1/2 and spin-0 particles is constructed. The model includes the oscillator-type interaction through a combination of Lorentz-vector and -tensor potentials. The analytical expressions for the wave functions and the order of the energy levels are discussed.

Altug Arda, Ramazan Sever

The effective mass Klein-Gordon equation in one dimension for the Woods-Saxon potential is solved by using the Nikiforov-Uvarov method. Energy eigenvalues and the corresponding eigenfunctions are computed. Results are also given for the constant mass case.

Jie Liu, Bin Liu, Libin Fu

We investigate the dynamics of converting cold bosonic atoms to molecules when an external magnetic field is swept across a Feshbach resonance. Our analysis relies on a zero temperature quantum microscopic model that accounts for many-body effects, triggering the association process. We show that the picture of two-body molecular production depicted by Landa

D. V. Ahluwalia, Cheng-Yang Lee, D. Schritt, T. F. Watson

Following the unexpected theoretical discovery of a mass dimension one fermionic quantum field of spin one half, we now present first results on two _local_ versions. The Dirac and Majorana fields of the standard model of particle physics are supplemented by their natural counterparts in the dark matter sector. The possibility that a mass dimension transmuti

Hai-Jhun Wanng

In this paper we postulate an algebraic model to explain how the symmetry of three lepton species plays its role in the Lorentz extension. Inspired by the two-to-one mapping between the group SL (2, C) and the Lorentz group, we design a mapping between SL (3, C) group, which displays the family symmetry, and a generalized Lorentz group. Following the convent

Constantino Tsallis

A recent paper by T. Dauxois entitled "Non-Gaussian distributions under scrutiny" is submitted to scrutiny. Several comments on its content are made, which constitute, at the same time, a brief state-of-the-art review of nonextensive statistical mechanics, a current generalization of the Boltzmann-Gibbs theory. Some inadvertences and misleading sente

Yun-Song Piao

In the eternally inflationary background driven by the metastable vacua of the landscape, it is possible that some local quantum fluctuations with the null energy condition violation can be large enough to stride over the barriers among different vacua, so that create some islands full of radiation in new vacua, and then these emergently thermalized islands

Ben Craps, Thomas Hertog, Neil Turok

The AdS/CFT correspondence allows us to map a dynamical cosmology to a dual quantum field theory living on the boundary of spacetime. Specifically, we study a five-dimensional model cosmology in type IIB supergravity, where the dual theory is an unstable deformation of $\N=4$ supersymmetric SU(N) gauge theory on $\Rbar\times S^3$. A one-loop computation show

Krzysztof T. Chyzy

The origin of asymmetric radio polarized emission and properties of magnetic fields in the Virgo Cluster spiral NGC4254 are investigated with help of "magnetic maps" presenting distributions of different magnetic field components over the entire galaxy, free of Faraday rotation and projection effects. We show that the dramatic variation of orientatio

V. Testa, N. Rea, R. P. Mignani, G. L. Israel

<Context>. We report on near-infrared (IR) observations of the three anomalous X-ray pulsars XTE J1810-197, 1RXS J1708-4009, 1E 1841-045 and the soft gamma-ray repeater SGR 1900+14, taken with the ESO-VLT, the Gemini, and the CFHT telescopes. <Aims>. This work is aimed at identifying and/or confirming the IR counterparts of these magnetars, as well as at mea

E391a Collaboration, J. K. Ahn

We performed a search for the $K^0_L \to π^0 ν\barν$ decay at the KEK 12-GeV proton synchrotron. No candidate events were observed. An upper limit on the branching ratio for the decay was set to be $6.7 \times 10^{-8}$ at the 90% confidence level.

Jack L. Uretsky

I summarize the history of theoretical predictions of, and experimental attempts to measure, pion-pion (S-wave) scattering lengths. Recent measurements at CERN confirm Weinberg's 1966 prediction of the I=2 scattering length and Basdevant and Lee's subsequent correction of the Weinberg I=0 value by inclusion of an S-wave I=0 resonance.

William Arveson

We show that states on tensor products of matrix algebras whose ranks are relatively small are {\em almost surely} entangled, but that states of maximum rank are not. More precisely, let $M=M_m(\mathbb C)$ and $N=M_n(\mathbb C)$ be full matrix algebras with $m\geq n$, fix an arbitrary state $ω$ of $N$, and let $E(ω)$ be the set of all states of $M\otimes N$

Anne Thomas

Chapter 1 is a short history of non-Euclidean geometry, which synthesises my readings of mostly secondary sources. Chapter 2 presents each of the main models of hyperbolic geometry, and describes the tesselation of the upper half-plane induced by the action of $PSL(2,\mathbb{Z})$. Chapter 3 gives background on symmetric spaces and word metrics. Chapter 4 the

Z. Bajnok, Zs. Simon

Integrable defects in two-dimensional integrable models are purely transmitting thus topological. By fusing them to integrable boundaries new integrable boundary conditions can be generated, and, from the comparison of the two solved boundary theories, explicit solutions of defect models can be extracted. This idea is used to determine the transmission facto

Adom Giffin

It has been shown that one can accommodate data (Bayes) and constraints (MaxEnt) in one method, the method of Maximum (relative) Entropy (ME) (Giffin 2007). In this paper we show a complex agent based example of inference with two different forms of information; moments and data. In this example, several agents each receive partial information about a system

Martin Cederwall

We give a preliminary discussion of how the addition of extra coordinates in M-theory, which together with the original ones parametrise a U-fold, can serve as a tool for formulating brane dynamics with manifest U-duality. The redundant degrees of freedom are removed by generalised self-duality constraints or calibration conditions made possible by the algeb

Kay Joerg Wiese, Pierre Le Doussal

In contrast to standard critical phenomena, disordered systems need to be treated via the Functional Renormalization Group. The latter leads to a coarse grained disorder landscape, which after a finite renormalization becomes non-analytic, thus overcoming the predictions of the seemingly exact dimensional reduction. We review recent progress on how the non-a

Shihshu Walter Wei

Characterizations of entire subsolutions for the 1-harmonic equation of a constant 1$-tension field are given with applications in geometry via transformation group theory. In particular, we prove that every level hypersurface of such a subsolution is calibrated and hence is area-minimizing over $\mathbb{R}$; and every 7-dimensional $SO(2)\times SO(6)$-invar

Christopher M. Graney

Work published in Sky and Telescope in 2004 discusses Galileo&#39;s observations of the star Mizar. These observations raise questions regarding Galileo&#39;s assumptions about the universe and the conclusions he drew from his observations. Galileo would have expected Mizar to reveal annual parallax and thus provide evidence of Earth&#39;s motion, but Mizar

Robert J. Adler, Gennady Samorodnitsky, Jonathan E. Taylor

Studying the geometry generated by Gaussian and Gaussian- related random fields via their excursion sets is now a well developed and well understood subject. The purely non-Gaussian scenario has, however, not been studied at all. In this paper we look at three classes of stable random fields, and obtain asymptotic formulae for the mean values of various geom

Radhakrishnan Nagarajan, Anand Nagarajan, Mariofanna Milanova

Developing fast and efficient algorithms for retrieval of objects to a given user query is an area of active research. The present study investigates retrieval of time series objects from a phoneme database to a given user pattern or query. The proposed method maps the one-dimensional time series retrieval into a sequence retrieval problem by partitioning th

Peter C. Richter

In this note we present two natural restrictions of the local Hamiltonian problem which are BQP-complete under Karp reduction. Restrictions complete for QCMA, QMA_1, and MA were demonstrated previously.

E. Dalessandro, B. Lanzoni, F. R. Ferraro, R. T. Rood

We have used multi-band high resolution HST WFPC2 and ACS observations combined with wide field ground-based observations to study the blue straggler star (BSS) population in the galactic globular cluster NGC 6388. As in several other clusters we have studied, the BSS distribution is found to be bimodal: highly peaked in the cluster center, rapidly decreasin

SciBooNE Collaboration, Yasuhiro Nakajima

SciBooNE is a new experiment at FNAL which will make precision neutrino-nucleus cross section measurements in the one GeV region. These measurements are essential for the future neutrino oscillation experiments. We started data taking in the antineutrino mode on June 8, 2007, and collected 5.19 \times 10^{19} protons on target (POT) before the accelerator sh

A. J. Buchmann

To obtain further information on the geometric shape of the nucleon, the proton charge form factor is decomposed into two terms, which are connected respectively with a spherically symmetric and an intrinsic quadrupole part of the proton&#39;s charge density. Quark model relations are employed to derive expressions for both terms. In particular, the proton&#

Lawrence Rudnick

I review some of the important and exciting recent advances that were presented at the 2007 conference on Extragalactic Jets in Girdwood, Alaska, using as a framework the scientific challenges presented by R. Blandford at the beginning of the meeting. Sprinkled throughout are thoughts about the marvelous prospects for jets in the next several years, as a hos

Lasse Rempe

We survey the definition of the radial Julia set of a meromorphic function (in fact, more generally, any &#34;Ahlfors islands map&#34;), and give a simple proof that the Hausdorff dimension of the reduced Julia set always coincides with the hyperbolic dimension.

Sandra Martinez, Noemi Wolanski

In this paper we study the following problem. For any $\ep>0$, take $u^{\ep}$ a solution of, $$ Łu^{\ep}:= {div}\Big(\di\frac {g(|\nabla \uep|)}{|\nabla \uep|}\nabla \uep\Big)=β_{\ep}(u^{\ep}),\quad u^{\ep}\geq 0. $$ A solution to $(P_{\ep})$ is a function $u^{\ep}\in W^{1,G}(Ω)\cap L^{\infty}(Ω)$ such that $$ \int_Ω g(|\nabla u^{\ep}|) \frac{\nabla u^{\ep}}

J M Tavares, M M Telo da Gama, A Nunes

A simple model of language evolution, proposed in \cite{K_N}, is characterized by a pay-off in communicative function, and by an error in learning, that measures the accuracy in language acquisition. In the mean field approximation, this model exhibits a critical coherence threshold, i.e. a minimal accuracy in the learning process is required to maintain lin

Martin Pohl, Peter Englmaier, Nicolai Bissantz

We present a new model of the three-dimensional distribution of molecular gas in the Milky Way Galaxy, based on CO line data. Our analysis is based on a gas-flow simulation of the inner Galaxy using smoothed-particle hydrodynamics (SPH) using a realistic barred gravitional potential derived from the observed COBE/DIRBE near-IR light distribution. The gas mod

Andres Diaz-Gil, Juan Garcia-Bellido, Margarita Garcia Perez, Antonio Gonzalez-Arroyo

We study the generation of magnetic fields during preheating within an scenario of hybrid inflation at the electroweak (EW) scale. We find that the non-perturbative and strongly out-of-equilibrium process of magnetic field production occurs along the lines predicted by Vachaspati many years ago. The system starts in the false vacuum at the end of inflation,

F. Cannata, M. V. Ioffe, D. N. Nishnianidze

The general solution of SUSY intertwining relations of first order for two-dimensional Schrödinger operators with position-dependent (effective) mass is built in terms of four arbitrary functions. The procedure of separation of variables for the constructed potentials is demonstrated in general form. The generalization for intertwining of second order is als

S. S. Afonin

A one-dimensional quantum mechanical model possessing mass gap, a gapless excitation, and an approximate parity doubling of energy levels is constructed basing on heuristic QCD-inspired arguments. The model may serve for illustrative purposes in considering the related dynamical phenomena in particle and nuclear physics.

Risi Kondor

Whenever we have a group acting on a class of functions by translation, the bispectrum offers a principled and lossless way of representing such functions invariant to the action. Unfortunately, computing the bispectrum is often costly and complicated. In this paper we propose a unitarily equivalent, but easier to compute set of invariants, which we call the

R. D. Hoffman, B. Muller, H. -T. Janka

We have studied detailed nucleosynthesis in the shocked surface layers of an Oxygen-Neon-Magnesium core collapse supernova with an eye to determining if the conditions are suitable for r process nucleosynthesis. We find no such conditions in an unmodified model, but do find overproduction of N=50 nuclei (previously seen in early neutron-rich neutrino winds)

Tom Chang, Cheng-chin Wu

We describe a new method that is both physically explicable and quantitatively accurate in describing the multifractal characteristics of intermittent events based on groupings of rank-ordered fluctuations. The generic nature of such rank-ordered spectrum leads it to a natural connection with the concept of one-parameter scaling for monofractals. We demonstr

Bernardo Abrego, Silvia Fernandez-Merchant, Jesus Leanos, Gelasio Salazar

The point sets of all known optimal rectilinear drawings of $K_n$ share an unmistakeable clustering property, the so--called {\em 3--decomposability}. It is widely believed that the underlying point sets of all optimal rectilinear drawings of $K_n$ are 3--decomposable. We give a lower bound for the minimum number of $(\le k)$--sets in a 3--decomposable $n$--

Joerg Zintl

The moduli stack of Deligne-Mumford stable curves of genus g admits a stratification, so that the number of nodes of the curves belonging to one stratum is constant. The irreducible components of the stratum corresponding to curves with exactly 3g-4 nodes are one-dimensional substacks. We show how they can be related to moduli stacks of (permutation classes

Olli Ahonen

The quantum key distribution protocol BB84, published by C. H. Bennett and G. Brassard in 1984, describes how two spatially separated parties can generate a random bit string fully known only to them by transmission of single-qubit quantum states. Any attempt to eavesdrop on the protocol introduces disturbance which can be detected by the legitimate parties.

Bing An Li

The decays of $Υ(1s)\toγ(η&#39;,η)$ are studied by an approach which has successfully predicted the ratio $\frac{Γ(J/ψ\toγη&#39;)}{Γ(J/ψ\toγη)}$. Strong dependence on quark mass has been found in the decays $(J/ψ, Υ(1s))\toγ(η&#39;,η)$. Very small decay rates of $Υ(1s)\toγ(η&#39;,η)$ are predicted.

W. Herfort, P. A. Zalesski

A finitely generated virtually free pro-p group with finite centralizers of its torsion elements is the free pro-p product of finite p-groups and a free pro-p factor.

Bojan Novakovic

We presented here the orbital parameters for five visual binary stars calculated by using the new method which we named Sector Grid Search. Orbital parameters were obtained for the following stars: WDS 00152+2722 = ADS 195, WDS 02202+2949 = ADS 1780, WDS 11550$-$5606 = HIP 58106, WDS 16256$-$2327 = ADS 10049 and WDS 16256$-$2327 = ADS 10045. In addition, the

M. Boglione, U. D&#39;Alesio, F. Murgia

In a perturbative QCD approach, with inclusion of spin and transverse momentum effects, experimental data on azimuthal asymmetries observed in polarized semi-inclusive deeply inelastic scattering and e+ e- annihilations can be used to determine the Sivers, transversity and Collins soft functions. By using these functions, within the same scheme, we predict p

K. Kleidis, A. Kuiroukidis, D. B. Papadopoulos, L. Vlahos

The excitation of cosmological perturbations in an anisotropic cosmological model and in the presence of a homogeneous magnetic field has been studied, using the ideal magnetohydrodynamic (MHD) equations. In this case, the system of partial differential equations which governs the evolution of the magnetized cosmological perturbations can be solved analytica

A. Pasquali, P. Castangia

We have collected archival data on NGC7673 to constrain the star-formation history that produced the young star clusters and the field stellar population in this galaxy during the last 2 Gyr. We have considered the sample of 50 star clusters detected by HST/WFPC2 in the UV, V and I bands and estimated their age, intrinsic reddening, and mass via comparison o

Belle Collaboration, Y. Nakahama, K. Sumisawa

We report a measurement of the CP-violating parameters in B0->K0S K0S decays based on a data sample of 657 million BBbar pairs collected at the Y(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. In this study, one neutral B meson is fully reconstructed in the B0->K0S K0S decay mode, and the flavor of the accompanying B meson

C. Austen Angell

We divide glass and viscous liquid sciences into two major research areas, the first dealing with how to avoid crystals and so access the viscous liquid state, and the second dealing with how liquids behave when no crystals form. We review some current efforts to elucidate each area, looking at strategies for vitrification of monatomic metals in the first, a

M. Szydlowski, W. Godlowski, J. Golbiak

The contemporary cosmic expansion is considered in the context of Modified Friedmann Dynamics (MOFD). We discuss some relativistic model exploring analogy to MOND modification of Newtonian dynamics. We argue that MOFD cosmologies can explain fraction of dark matter in the accelerating Universe. We discuss some observational constraints on possible evolutiona

V. V. Gvaramadze, A. Gualandris, S. Portegies Zwart

We propose an explanation for the origin of hyperfast neutron stars (e.g. PSR B1508+55, PSR B2224+65, RX J0822-4300) based on the hypothesis that they could be the remnants of a symmetric supernova explosion of a high-velocity massive star (or its helium core) which attained its peculiar velocity (similar to that of the neutron star) in the course of a stron

Marek J. Sarna

We perform evolutionary calculations of binary stars to find progenitors of system with parameters similar to the eclipsing binary system V228. We show that a V228 binary system may be formed starting with an initial binary system which has a low main sequence star as an accretor. We also show that the best fitting model implies loss of about 50 per cent of

Jacek Mulak, Maciej Mulak

The second moment of the sublevels within the initial state | αSLJ > which constitutes a natural and adequate measure of the crystal-field (CF) effect can be redefined as sigma^{2}=1/(2J+1)\sum_{k} S_{k}^{2} A_{k}^{2}, where S_{k}=[1/(2k+1)\sum_{q}|B_{kq}|^2]^{1/2} is the so-called 2^{k}-pole CF strength, whereas A_{k}= < αSLJ||C^{(k)}||αSLJ > the reduced ma

V. V. Gvaramadze

The proper motion of massive stars could cause them to explode far from the geometric centers of their wind-driven bubbles and thereby could affect the symmetry of the resulting diffuse supernova remnants. We use this fact to explain the origin of SNRs consisting of two partially overlapping shells (e.g. Cygnus Loop, 3C 400.2, etc.).

Jens Christian Claussen

The coevolutionary dynamics in finite populations currently is investigated in a wide range of disciplines, as chemical catalysis, biological evolution, social and economic systems. The dynamics of those systems can be formulated within the unifying framework of evolutionary game theory. However it is not a priori clear which mathematical description is appr

Ting Zhang, Daoyuan Fang

In this note, by constructing suitable approximate solutions, we prove the existence of global weak solutions to the compressible Navier-Stokes equations with density-dependent viscosity coefficients in the whole space $\mathbb{R}^N$, $N\geq2$ (or exterior domain), when the initial data are spherically symmetric. In particular, we prove the existence of sphe

Jens Christian Claussen

When a chaotic system is to be stabilized to a unstable orbit, delayed measurement of the system limits the applicability of chaos control techniqes. These limitations are analyzed and control schemes as linear predictive logging control (LPLC) and memory difference control (MDC) are introduced which can overcome those limitations for chaos control schemes t

Sergey Naumenko, Andrew Podlazov, Mikhail Burtsev, George Malinetsky

The genetic code markup is the assignment of stop codons. The standard genetic code markup ensures the maximum possible stability of genetic information with respect to two fault classes: frameshift and nonsense mutations. There are only 528 (about 1,3% of total number) optimal markups in the set of markups having 3 stop codons. Among the sets of markups wit

Yue Zhang, Haipeng An, Xiangdong Ji, Rabindra N. Mohapatra

In minimal left-right symmetric theories, the requirement of parity invariance allows only one complex phase in the Higgs potential and one in the Yukawa couplings, leading to a two-phase theory with both spontaneous and explicit CP violations. We present a systematic way to solve the right-handed quark mixing matrix analytically in this model and find that

Jens Christian Claussen

Many complex biological, social, and economical networks show topologies drastically differing from random graphs. But, what is a complex network, i.e.\ how can one quantify the complexity of a graph? Here the Offdiagonal Complexity (OdC), a new, and computationally cheap, measure of complexity is defined, based on the node-node link cross-distribution, whos

Bel G. Raggad, Sahbi Sidhom

Despite all visible dividers, the Internet is getting us closer and closer, but with a great price. Our security is the price. The international community is fully aware of the urgent need to secure the cyberspace as you see the multiplication of security standards and national schemes interpreting them beyond borders: ISO 15408, ISO 17799, and ISO 27001. Ev

Philippe G. LeFloch, Cristinel Mardare, Sorin Mardare

Assuming minimal regularity assumptions on the data, we revisit the classical problem of finding isometric immersions into the Minkowski spacetime for hypersurfaces of a Lorentzian manifold. Our approach encompasses metrics having Sobolev regularity and Riemann curvature defined in the distributional sense, only. It applies to timelike, spacelike, or null hy

Seiichiro Tani, Hirotada Kobayashi, Keiji Matsumoto

This paper gives the first separation of quantum and classical pure (i.e., non-cryptographic) computing abilities with no restriction on the amount of available computing resources, by considering the exact solvability of a celebrated unsolvable problem in classical distributed computing, the ``leader election problem&#39;&#39; on anonymous networks. The goa

Guodong Pang, Rishi Talreja, Ward Whitt

This is an expository review paper illustrating the ``martingale method&#39;&#39; for proving many-server heavy-traffic stochastic-process limits for queueing models, supporting diffusion-process approximations. Careful treatment is given to an elementary model -- the classical infinite-server model $M/M/\infty$, but models with finitely many servers and cus

A. Sopczak, A. Freitas, C. Milstene, M. Schmitt

Most supersymmetric models predict new particles within the reach of the next generation of colliders. For an understanding of the model structure and the mechanism(s) of electroweak symmetry breaking, it is important to know the masses of the new particles precisely. The measurement of the mass of the scalar partner of the top quark (stop) at an e+e- collid

Neri Merhav

In an earlier work, the statistical physics associated with finite--temperature decoding of code ensembles, along with the relation to their random coding error exponents, were explored in a framework that is analogous to Derrida&#39;s random energy model (REM) of spin glasses, according to which the energy levels of the various spin configurations are indep

Seiya Nishiyama, Joao da Providencia, Constanca Providencia, Flavio Cordeiro

Extended supersymmetric sigma-model is given, standing on the SO(2N+1) Lie algebra of fermion operators composed of annihilation-creation operators and pair operators. Canonical transformation, the extension of the SO(2N) Bogoliubov transformation to the SO(2N+1) group, is introduced. Embedding the SO(2N+1) group into an SO(2N+2) group and using SO(2N+2)/U(N

A. Sopczak, A. Finch, A. Freitas, C. Milstene

Scalar top studies at the ILC are reviewed from initial sensitivity studies to a new precision mass determination method.

Michel H. G. Tytgat

The Inert Doublet Model (IDM) is a two doublet extension of the Higgs-Brout-Englert sector of the Standard Model with a Z_2 symmetry in order to prevent FCNC. If the Z_2 symmetry is not spontaneously broken, the lightest neutral extra scalar is a dark matter candidate. We briefly review the phenomenology of the model, emphasizing its relevance for the issue

Colin Snodgrass, Stephen C. Lowry, Alan Fitzsimmons

We present photometry on 23 Jupiter Family Comets (JFCs) observed at large heliocentric distance, primarily using the 2.5m Isaac Newton Telescope (INT). Snap-shot images were taken of 17 comets, of which 5 were not detected, 3 were active and 9 were unresolved and apparently inactive. These include 103P/Hartley 2, the target of the NASA Deep Impact extended

I. Wayan Sudiarta, D. J. Wallace Geldart

We extend our finite difference time domain method for numerical solution of the Schrodinger equation to cases where eigenfunctions are complex-valued. Illustrative numerical results for an electron in two dimensions, subject to a confining potential V(x,y), in a constant perpendicular magnetic field demonstrate the accuracy of the method.

Zbigniew S. Szewczak

An operator form of asymptotic expansions for Markov chains is established. Coefficients are given explicitly. Such expansions require a certain modification of the classical spectral method. They prove to be extremely useful within the context of large deviations.

Ji-Rong Ren, Tao Zhu, Yi-Shi Duan

Scroll waves exist ubiquitously in three-dimensional excitable media. It&#39;s rotation center can be regarded as a topological object called vortex filament. In three-dimensional space, the vortex filaments usually form closed loops, and even linked and knotted. In this letter, we give a rigorous topological description of knotted vortex filaments. By using

Ji-Rong Ren, Tao Zhu, Yi-Shi Duan

Optical vortices as topological objects exist ubiquitously in nature. In this paper, by making use of the $ϕ$-mapping topological current theory, we investigate the topology in the closed and knotted optical vortices. The topological inner structure of the optical vortices are obtained, and the linking of the knotted optical vortices is also given.

Bhaskar Sen Gupta, Shankar P. Das

In this report we address the question whether aging in the non equilibrium glassy state is controlled by the equilibrium alpha-relaxation process which occur at temperatures above Tg. Recently Lunkenheimer et. al. [Phys. Rev. Lett. 95, 055702 (2005)] proposed a model for the glassy aging data of dielectric relaxation using a modified Kohlrausch-Williams-Wat

Lisa M. Young, Martin Bureau, Michele Cappellari

We present interferometric observations resolving the CO emission in the four gas-rich lenticular galaxies NGC 3032, NGC 4150, NGC 4459, and NGC 4526, and we compare the CO distribution and kinematics to those of the stars and ionized gas. Counterrotation documents an external origin for the gas in at least one case (NGC 3032), and the comparisons to stellar

Fotis P. Gavriil, Rim. Dib, Victoria M. Kaspi

After 6 years of quiescence, Anomalous X-ray Pulsar (AXP) 4U 0142+61 entered an active phase in 2006 March that lasted several months. During the active phase, several bursts were detected, and many aspects of the X-ray emission changed. We report on the discovery of six X-ray bursts, the first ever seen from this AXP in ~10 years of Rossi X-ray Timing Explo

Michael Anshelevich

The Appell-type polynomial family corresponding to the simplest non-commutative derivative operator turns out to be connected with the Boolean probability theory, the simplest of the three universal non-commutative probability theories (the other two being free and tensor/classical probability). The basic properties of the Boolean Appell polynomials are desc

Dao-Shun Wang, Feng Yi, Xiaobo Li

Visual secrete sharing (VSS) is an encryption technique that utilizes human visual system in the recovering of the secret image and it does not require any complex calculation. Pixel expansion has been a major issue of VSS schemes. A number of probabilistic VSS schemes with minimum pixel expansion have been proposed for binary secret images. This paper prese

M. Vengalattore, S. R. Leslie, J. Guzman, D. M. Stamper-Kurn

Helical spin textures in a $^{87}$Rb F=1 spinor Bose-Einstein condensate are found to decay spontaneously toward a spatially modulated structure of spin domains. This evolution is ascribed to magnetic dipolar interactions that energetically favor the short-wavelength domains over the long-wavelength spin helix. This is confirmed by eliminating the dipolar in

Seigo Takahashi, Akio Tajima, Akihisa Tomita

A single-photon avalanche detector (SPAD) for high-speed quantum-key generation has successfully been developed. It has the highest photon detection repetition frequency and the lowest dark count rate in the world, as a board-mountable sub-system. The SPAD consists of an ultra-small dual-avalanche photodiode (APD) module and a novel discriminator. The APD mo

Md. Mokammel Haque, Al-Sakib Khan Pathan, Byung Goo Choi, Choong Seon Hong

In spite of previous widely held belief of the incompatibility of public key cryptography (PKC) schemes for wireless sensor networks (WSNs), some recent works have shown that, PKC based schemes could be implemented for such networks in some ways. The major challenge of employing a PKC scheme in wireless sensor network is posed by the limitations of resources

Al-Sakib Khan Pathan, Gihyuk Heo, Choong Seon Hong

In this paper, we consider a particular type of deployment scenario of a distributed sensor network (DSN), where sensors of different types and categories are densely deployed in the same target area. In this network, the sensors are associated with different groups, based on their functional types and after deployment they collaborate with one another in th

Al-Sakib Khan Pathan, Choong Seon Hong

With the recent proliferation of distributed systems and networking, remote authentication has become a crucial task in many networking applications. Various schemes have been proposed so far for the two-party remote authentication; however, some of them have been proved to be insecure. In this paper, we propose an efficient timestamp-based password authenti

Al-Sakib Khan Pathan, Choong Seon Hong, Tatsuya Suda

This paper proposes a novel remote user authentication scheme using smart cards which allows both the authentication server (AS) and the user to verify authenticity of each other. Our scheme is efficient enough to resist the known attacks that could be launched against remote user authentication process.

Al-Sakib Khan Pathan, Choong Seon Hong

This paper proposes an efficient approach of secure clustering in distributed sensor networks. The clusters or groups in the network are formed based on offline rank assignment and predistribution of secret keys. Our approach uses the concept of weakly connected dominating set (WCDS) to reduce the number of cluster-heads in the network. The formation of clus

Al-Sakib Khan Pathan, Choong Seon Hong

The impact of extreme events across the globe is extraordinary which continues to handicap the advancement of the struggling developing societies and threatens most of the industrialized countries in the globe. Various fields of Information and Communication Technology have widely been used for efficient disaster management; but only to a limited extent thou

Al-Sakib Khan Pathan, Choong Seon Hong, Hyung-Woo Lee

The miniaturization process of various sensing devices has become a reality by enormous research and advancements accomplished in Micro Electro-Mechanical Systems (MEMS) and Very Large Scale Integration (VLSI) lithography. Regardless of such extensive efforts in optimizing the hardware, algorithm, and protocols for networking, there still remains a lot of sc

Al-Sakib Khan Pathan, Hyung-Woo Lee, Choong Seon Hong

Wireless Sensor Network (WSN) is an emerging technology that shows great promise for various futuristic applications both for mass public and military. The sensing technology combined with processing power and wireless communication makes it lucrative for being exploited in abundance in future. The inclusion of wireless communication technology also incurs v

Al-Sakib Khan Pathan, Humayun Kadir Islam, Sabit Anjum Sayeed, Farruk Ahmed

In recent years, the proliferation of mobile computing devices has driven a revolutionary change in the computing world. The nature of ubiquitous devices makes wireless networks the easiest solution for their interconnection. This has led to the rapid growth of several wireless systems like wireless ad hoc networks, wireless sensor networks etc. In this pape

Peter Hoff

Orthonormal matrices play an important role in reduced-rank matrix approximations and the analysis of matrix-valued data. A matrix Bingham-von Mises-Fisher distribution is a probability distribution on the set of orthonormal matrices that includes linear and quadratic terms, and arises as a posterior distribution in latent factor models for multivariate and

Andre Sopczak

Results of detailed simulations of the charge transfer inefficiency of a prototype serial readout CCD chip are reported. The effect of radiation damage on the chip operating in a particle detector at high frequency at a future accelerator is studied, specifically the creation of two electron trap levels, 0.17 eV and 0.44 eV below the bottom of the conduction

SciBooNE Collaboration, Yasuhiro Nakajima

The precise knowledge of the single pion production cross-section of neutrino around the ~1 GeV energy region is an essential ingredient in the interpretation of neutrino oscillation experiments. The unique opportunities and prospects of single pion measurements at SciBooNE are described.

Víctor Villar, Jesús Gallego, Pablo G. Pérez-González, Sergio Pascual

We present the results of an Halpha near-infrared narrow-band survey searching for star-forming galaxies at redshift z=0.84. This work is an extension of our previous narrow-band studies in the optical at lower redshifts. After removal of stars and redshift interlopers (using spectroscopic and photometric redshifts), we build a complete sample of 165 Halpha

P. Marios Petropoulos

We analyze the class of four-dimensional N = 4 supergravities obtained by gauging the axionic shift and axionic rescaling symmetries. These theories are formulated with the machinery of embedding tensors and shown to be deducible from higher dimensions using a Scherk--Schwarz reduction with a twist by a non-compact symmetry. This allows to evade the usual un

Mateusz Pipien

The main goal of this paper is an application of Bayesian inference in testing the relation between risk and return on the financial instruments. On the basis of the Intertemporal CAPM model we built a general sampling model suitable in analysing such a relationship. The most important feature of our assumptions is that the skewness of the conditional distri

Ivan Mirković, Maxim Vybornov

We construct Nakajima&#39;s quiver varieties of type A in terms of conjugacy classes of matrices and (non-Slodowy&#39;s) transverse slices naturally arising from affine Grassmannians. In full generality quiver varieties are embedded into Beilinson-Drinfeld Grassmannians of type A. Our construction provides a compactification of Nakajima&#39;s quiver varietie

G Briscoe

We start with a discussion of the relevant literature, including Nature Inspired Computing as a framework in which to understand this work, and the process of biomimicry to be used in mimicking the necessary biological processes to create Digital Ecosystems. We then consider the relevant theoretical ecology in creating the digital counterpart of a biological