October 2006 arXiv papers — page 12

K. B. Efetov, I. A. Garifullin, A. F. Volkov, K. Westerholt

We review the present status of the experimental and theoretical research on the proximity effect in heterostructures composed of superconducting (S) and ferromagnetic (F) thin films. First, we discuss traditional effects originating from the oscillatory behavior of the superconducting pair wave function in the F-layer. Then, we concentrate on recent theoret

P. Laursen, J. Sommer-Larsen

We present results obtained with a 3D, Ly alpha radiative transfer code, applied to a fully cosmological galaxy formation simulation. The developed Monte Carlo code is capable of treating an arbitrary distribution of source Ly alpha emission, neutral hydrogen density, temperature, and peculiar velocity of the interstellar medium. We investigate the influence

A. V. Chaplik, T. Ya. Tudorovskiy

We study an interaction of 2D quasiparticles with linear dispersion (graphene) with impurity potentials. It is shown that in 1D potential well (quantum wire) there are discrete levels, corresponding to localized states, whereas in 2D well (quantum dot) there are no such states. Scattering cross-section of electrons (holes) of graphene by an axially symmetric

Satoru Saito, Noriko Saitoh

By studying various rational integrable maps on $\mathbf{\hat C}^d$ with $p$ invariants, we show that periodic points form an invariant variety of dimension $\ge p$ for each period, in contrast to the case of nonintegrable maps in which they are isolated. We prove the theorem: {\it `If there is an invariant variety of periodic points of some period, there is

Valerio Faraoni

The Dolgov-Kawasaki instability discovered in the matter sector of the modified gravity scenario incorporating a 1/R correction to Einstein gravity is studied in general f(R) theories. A stability condition is found in the metric version of these theories to help ruling out models that are unviable from the theoretical point of view.

Cecilia Bejarano, Ernesto F. Eiroa, Claudio Simeone

In this article we construct cylindrical thin-shell wormholes in the context of global cosmic strings. We study the stability of static configurations under perturbations preserving the symmetry and we find that the throat tends to collapse or expand, depending only on the direction of the velocity perturbation.

P. Zinn-Justin

The integrable loop model with mixed boundary conditions based on the 1-boundary extended Temperley--Lieb algebra with loop weight 1 is considered. The corresponding qKZ equation is introduced and its minimal degree solution described. As a result, the sum of the properly normalized components of the ground state in size L is computed and shown to be equal t

Jochen Walter, Erik Tholen, Joachim Sjostrand, David B. Haviland

We investigate by theory and experiment, the Josephson junction switching current detector in an environment with frequency dependent damping. Analysis of the circuit's phase space show that a favorable topology for switching can be obtained with overdamped dynamics at high frequencies. A pulse-and-hold method is described, where a fast switch pulse brin

Alessandra Buonanno, Gregory B. Cook, Frans Pretorius

We investigate the dynamics and gravitational-wave (GW) emission in the binary merger of equal-mass black holes as obtained from numerical relativity simulations. Results from the evolution of three sets of initial data are explored in detail, corresponding to different initial separations of the black holes. We find that to a good approximation the inspiral

Thomas Baird

Consider the space Hom(Z^n,G) of pairwise commuting n-tuples of elements in a compact Lie group G. This forms a real algebraic variety, which is generally singular. In this paper, we construct a desingularization of the generic component of Hom(Z^n,G), which allows us to derive formulas for its ordinary and equivariant cohomology in terms of the Lie algebra

R. Nath, P. Pedri, L. Santos

We analyze the scattering of bright solitons in dipolar Bose-Einstein condensates placed in unconnected layers. Whereas for short-range interactions unconnected layers are independent, a remarkable consequence of the dipole interaction is the appearance of novel nonlocal interlayer effects. In particular, we show that the interlayer interaction leads to an e

Ricardo Fraiman, Ana Justel, Marcela Svarc

In this paper we introduce two procedures for variable selection in cluster analysis and classification rules. One is mainly oriented to detect the noisy non-informative variables, while the other deals also with multicolinearity. A forward-backward algorithm is also proposed to make feasible these procedures in large data sets. A small simulation is perform

Paul A. Pearce, Jorgen Rasmussen

A lattice model of critical dense polymers is solved exactly for finite strips. The model is the first member of the principal series of the recently introduced logarithmic minimal models. The key to the solution is a functional equation in the form of an inversion identity satisfied by the commuting double-row transfer matrices. This is established directly

Tomasz Stachowiak, Marek Szydlowski

We discuss the effects of a (possibly) negative $(1+z)^6$ type contribution to the Friedmann equation. No definite answer can be given as to the presence and magnitude of a particular mechanism, because any test using the general relation $H(z)$ is able to estimate only the total of all sources of such a term. That is why we describe four possibilities: 1) g

Jonathan C. Mattingly, Toufic M. Suidan, Eric Vanden-Eijnden

We study a system of stochastically forced infinite-dimensional coupled harmonic oscillators. Although this system formally conserves energy and is not explicitly dissipative, we show that it has a nontrivial invariant probability measure. This phenomenon, which has no finite dimensional equivalent, is due to the appearance of some anomalous dissipation mech

Kentaro Somiya, Keisuke Goda, Yanbei Chen, Eugeniy E. Mikhailov

Interferometers with kilometer-scale arms have been built for gravitational-wave detections on the ground; ones with much longer arms are being planned for space-based detection. One fundamental motivation for long baseline interferometry is from displacement noise. In general, the longer the arm length L, the larger the motion the gravitational-wave induces

H. Belich, E. L. Graca, M. A. Santos, I. V. Vancea

We formulate the finite temperature theory for the free thermal excitations of the bosonic string in the anti-de Sitter (AdS) spacetime in the Thermo Field Dynamics (TFD) approach. The spacetime metric is treated exactly while the string and the thermal reservoir are semiclassically quantized at the first order perturbation theory with respect to the dimensi

Richard G. Clegg

This paper describes a framework for analysing matches in multiple data sets. The framework described is quite general and can be applied to a variety of problems where matches are to be found in data surveyed at a number of locations (or at a single location over a number of days). As an example, the framework is applied to the problem of false matches in l

Yuri Bakhtin, Jonathan C. Mattingly

We consider an infinite-dimensional dynamical system with polynomial nonlinearity and additive noise given by a finite number of Wiener processes. By studying how randomness is spread by the system we develop a counterpart of Hormander's classical theory in this setting. We study the distributions of finite-dimensional projections of the solutions and gi

Peter Berlin, Baris Nakiboglu, Bixio Rimoldi, Emre Telatar

In a remarkable paper published in 1976, Burnashev determined the reliability function of variable-length block codes over discrete memoryless channels with feedback. Subsequently, an alternative achievability proof was obtained by Yamamoto and Itoh via a particularly simple and instructive scheme. Their idea is to alternate between a communication and a con

S. Galtier, E. Buchlin

Solar wind magnetic fluctuation spectra exhibit a significant power law steepening at frequencies f>1Hz. The origin of this multi-scaling is investigated through dispersive Hall magnetohydrodynamics. We perform three-dimensional numerical simulations in the framework of a highly turbulent shell model and show that the large-scale magnetic fluctuations are ch

Ernest Ma

In an improved application of the tetrahedral symmetry A_4 first introduced by Ma and Rajasekaran, supplemented by the discrete symmetry Z_3 as well as supersymmetry, a two-parameter form of the neutrino mass matrix is derived which exhibits the tribimaximal mixing of Harrison, Perkins, and Scott. This form is the same one obtained previously by Altarelli an

Josep M. Pons

A brief overview of dimensional reductions for diffeomorphism invariant theories is given. The distinction between the physical idea of compactification and the mathematical problem of a consistent truncation is discussed, and the typical ingredients of the latter --reduction of spacetime dimensions and the introduction of constraints-- are examined. The con

N. A. Logoboy, E. B. Sonin

Propagation of the magnetization waves along domain walls (2D magnons) in a superconducting ferromagnet has been studied theoretically. The magnetostatic fields (long-range dipole-dipole interaction) have a crucial effect on the spectrum of 2D magnons. But this effect is essentially affected by the superconducting Meissner currents, which screen the magnetos

A. Mildenberger, F. Evers, A. D. Mirlin, J. T. Chalker

We investigate numerically the quasiparticle density of states $\varrho(E)$ for a two-dimensional, disordered superconductor in which both time-reversal and spin-rotation symmetry are broken. As a generic single-particle description of this class of systems (symmetry class D), we use the Cho-Fisher version of the network model. This has three phases: a therm

V. Tatischeff, J. -P. Thibaud

The high 6-Li abundances recently measured in metal-poor halo stars are far above the value predicted by Big Bang nucleosynthesis. They cannot be explained by galactic cosmic-ray interactions in the interstellar medium either. Various pre-galactic sources of 6-Li have been proposed in the literature. We study the possibility that the observed 6-Li was produc

Werner Bernreuther, Michael Fuecker, Zong-Guo Si

In this paper we determine the weak-interaction corrections of order $α_s^2α$ to hadronic top-quark pair production. First we compute the one-loop weak corrections to $t \bar t$ production due to gluon fusion and the order $α_s^2α$ corrections to $t \bar t$ production due to (anti)quark gluon scattering in the Standard Model. With our previous result this yi

S. Baessler, V. V. Nesvizhevsky, K. V. Protasov, A. Yu. Voronin

We present a new constraint for the axion monopole-dipole coupling in the range of 1 micrometer to a few millimeters, previously unavailable for experimental study. The constraint was obtained using our recent results on the observation of neutron quantum states in the Earth's gravitational field. We exploit the ultimate sensitivity of ultra-cold neutron

Zhenning Kong, Edmund M. Yeh

Percolation theory has become a useful tool for the analysis of large-scale wireless networks. We investigate the fundamental problem of characterizing the critical density $λ_c^{(d)}$ for $d$-dimensional Poisson random geometric graphs in continuum percolation theory. By using a probabilistic analysis which incorporates the clustering effect in random geome

Yuan-Guo Xu, Ru-Min Wang, Ya-Dong Yang

We study the decays $B\to K^{(*)}\ell^+\ell^-$ and $B_s\to \ell^+\ell^- (\ell=e,μ)$ in the minimal supersymmetric standard model with R-parity violation (RPV). From the recent measurements of their branching ratios, we have derived new upper bounds on the relevant RPV coupling products, which are stronger than the existing ones. Using the constrained paramet

M. Dobsicek, G. Johansson, V. S. Shumeiko, G. Wendin

We discuss the implementation of an iterative quantum phase estimation algorithm, with a single ancillary qubit. We suggest using this algorithm as a benchmark for multi-qubit implementations. Furthermore we describe in detail the smallest possible realization, using only two qubits, and exemplify with a superconducting circuit. We discuss the robustness of

Francisco S. N. Lobo

The van der Waals quintessence equation of state is an interesting scenario for describing the late universe, and seems to provide a solution to the puzzle of dark energy, without the presence of exotic fluids or modifications of the Friedmann equations. In this work, the construction of inhomogeneous compact spheres supported by a van der Waals equation of

Y. Farzan, A. Yu. Smirnov

Discovery of the CP-violation in the lepton sector is one of the challenges of the particle physics. We search for possible principles, symmetries and phenomenological relations that can lead to particular values of the CP-violating Dirac phase, $δ$. In this connection we discuss two extreme cases: the zero phase, $δ= 0$, and the maximal CP-violation, $δ= \p

Adam Falkowski

Pseudo-Goldstone bosons in 4D strongly coupled theories have a dual description in terms of 5D gauge theories in warped backgrounds. We introduce systematic methods of computing the pseudo-Goldstone potential for an arbitrary warp factor in 5D. When applied to electroweak symmetry breaking, our approach clarifies the relation of physical observables to geome

Houri Ziaeepour

We present a nonparametric method to determine the sign of $w+1$ in the equation of state of dark energy. It is based on geometrical behaviour and is more tolerant to uncertainties of other cosmological parameters than fitting methods. It permits to distinguish between different classes of dark energy models even with relatively low precision data. We apply

O. Pages, A. V. Postnikov, A. Chafi, D. Bormann

The recent finding of a 1-bond->2-phonon `percolation'-type behaviour in several random zincblende alloys, supporting an unsuspected 1-bond->2-mode behaviour in the bond length distribution, renews interest for a discussion of CuPt-type spontaneous ordering (CPSO) as a purely intrinsic effect. We investigate this key issue from both experimental (Raman s

Sanjib Kumar Agarwalla, Sandhya Choubey, Amitava Raychaudhuri

We underscore the physics advantage of an experiment where neutrinos produced in a beta-beam facility at CERN are observed in a large magnetized iron calorimeter (ICAL) at the India-based Neutrino Observatory (INO). The CERN-INO distance is close to the so-called "magic" baseline which helps evade some of the parameter degeneracies and allows for a b

N. Graham

A recent study demonstrated the existence of oscillons -- extremely long-lived localized configurations that undergo regular oscillations in time -- in spontaneously broken SU(2) gauge theory with a fundamental Higgs particle whose mass is twice the mass of the gauge bosons. This analysis was carried out in a spherically symmetric ansatz invariant under comb

S. Mayburov

Information-theoretical restrictions on the information transfer in quantum measurements are studied. They are derived for the measurement of system S by detector D, registrated and processed by information system O. The formalism of inference maps in Hilbert space is used for it; it permit to calculate O restricted state which contains available for O infor

Akishi Kato

The a-maximization technique proposed by Intriligator and Wecht allows us to determine the exact R-charges and scaling dimensions of the chiral operators of four-dimensional superconformal field theories. The problem of existence and uniqueness of the solution, however, has not been addressed in general setting. In this paper, it is shown that the a-function

Marie-Amelie Morlais

In this paper, we study a class of quadratic Backward Stochastic Differential Equations (BSDEs) which arises naturally when studying the problem of utility maximization with portfolio constraints. We first establish existence and uniqueness results for such BSDEs and then, we give an application to the utility maximization problem. Three cases of utility fun

Tsutomu Kobayashi, Masato Minamitsuji

We study scalar cosmological perturbations in a braneworld model with a bulk Gauss-Bonnet term. For an anti-de Sitter bulk, the five-dimensional perturbation equations share the same form as in the Randall-Sundrum model, which allows us to obtain metric perturbations in terms of a master variable. We derive the boundary conditions for the master variable fro

A. E. Mironov

We construct discrete analogues of the Dixmier operators, that is, commuting difference operators corresponding to a spectral curve of genus 1 whose coefficients are polynomials of the discrete variable.

Yong Kong

The classical monomer-dimer model in two-dimensional lattices has been shown to belong to the \emph{``#P-complete''} class, which indicates the problem is computationally ``intractable''. We use exact computational method to investigate the number of ways to arrange dimers on $m \times n$ two-dimensional rectangular lattice strips with fixed dimer density $\

Wolfgang Wagner

This article reports on recent searches for single-top-quark production by the CDF and DO collaborations at the Tevatron. Neither two CDF analyses, using data corresponding to 695 pb^-1 of integrated luminosity, nor a DO search based on 370 pb^-1 of data can establish a signal for this standard model process. These null results translate in upper limits on t

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

We discuss dispersion representations for the triangle diagram $F(p_1^2,p_2^2,q^2)$, the single dispersion representation in $q^2$ and the double dispersion representation in $p_1^2$ and $p_2^2$, with special emphasis on the appearance of the anomalous singularities and the anomalous cuts in these representations. For the double dispersion representation in

Ki Hyoung Ko, Jang Won Lee

We propose an algorithm for deciding whether a given braid is pseudo-Anosov, reducible, or periodic. The algorithm is based on Garside's weighted decomposition and is polynomial-time in the word-length of an input braid. Moreover, a reduction system of circles can be found completely if the input is a certain type of reducible braids.

Yuan-Ben Dai, Xin-Qiang Li, Shi-Lin Zhu, Ya-Bing Zuo

Using the soft-pion theorem and the assumption on the final-state interactions, we include the contribution of $DK$ continuum into the QCD sum rules for $D_{sJ}(2317)$ meson. We find that this contribution can significantly lower the mass and the decay constant of $D_s(0^+)$ state. For the value of the current quark mass $m_c(m_c)=1.286 {\rm GeV}$, we obtain

Jae-Seung Jeong, Hyun-Woo Lee

We study a ballistic spin field-effect transistor (SFET) with special attention to the issue of multi-channel effects. The conductance modulation of the SFET as a function of the Rashba spin-orbit coupling strength is numerically examined for the number of channels ranging from a few to close to 100. Even with the ideal spin injector and collector, the condu

D. Darcet, D. Sornette

Strong reciprocity is a fundamental human characteristic associated with our extraordinary sociality and cooperation. Laboratory experiments on social dilemma games and many field studies have quantified well-defined levels of cooperation and propensity to punish/reward. The level of cooperation is observed to be strongly dependent on the availability of pun

Yu Bing Dong, Chung Wen Kao, Shin Nan Yang, Yu Chun Chen

The general form of the cross section as well as the polarizations of electron-deuteron elastic scattering are given. Two-photon exchange effects are analyzed. Possible signatures of the two-photon exchange effects in the electron-deuteron elastic scattering are discussed.

F. Fiore, D. Guetta, S. Piranomonte, V. D'Elia

We present a detailed analysis of the selection effects that plague GRB observations. We find that these effects may partially explain the different redshift distributions between BeppoSax/HETE2 and Swift bursts. It is mandatory to consider these effects to determine the redshift evolution of GRBs.

Eric M. Rains

Associated to any subspace arrangement is a "De Concini-Procesi model", a certain smooth compactification of its complement, which in the case of the braid arrangement produces the Deligne-Mumford compactification of the moduli space of genus 0 curves with marked points. In the present work, we calculate the integral homology of real De Concini-Proce

Xiao-Song Wang

We propose a fluidic continuum model of vacuum and a sink flow model of microscopic particles. The movements of a microscopic particle driven by a stochastic force was studied based on stochastic mechanics. We show that there exists a generalized Schr\"{o}dinger equation for the microscopic particle.

V. Ejov, J. A. Filar, S. K. Lucas, P. Zograf

We exhibit a characteristic structure of the class of all regular graphs of degree d that stems from the spectra of their adjacency matrices. The structure has a fractal threadlike appearance. Points with coordinates given by the mean and variance of the exponentials of graph eigenvalues cluster around a line segment that we call a filar. Zooming-in reveals

B. Szczerbinska, T. Sato, K. Kubodera, T. -S. H. Lee

Reliable estimates of neutrino-nucleus reactions in the resonance-excitation region play an important role in many of the on-going and planned neutrino oscillation experiments. We study here neutrino-nucleus reactions in the delta-particle excitation region with the use of neutrino pion-production amplitudes calculated in a formalism in which the resonance c

The BABAR Collaboration, B. Aubert

We perform an amplitude analysis of the decays B0->phi K^*_2(1430)0, phi K^*(892)0, and phi(K pi)^0_S-wave with a sample of about 384 million BBbar pairs recorded with the BABAR detector. The fractions of longitudinal polarization f_L of the vector-tensor and vector-vector decay modes are measured to be 0.853 +0.061-0.069 +-0.036 and 0.506 +-0.040 +-0.015, r

Ingemar Bengtsson

This is a review of the problem of Mutually Unbiased Bases in finite dimensional Hilbert spaces, real and complex. Also a geometric measure of "mubness" is introduced, and applied to some recent calculations in six dimensions (partly done by Bjorck and by Grassl). Although this does not yet solve any problem, some appealing structures emerge.

S. Slama, S. Bux, G. Krenz, C. Zimmermann

Collective interaction of light with an atomic gas can give rise to superradiant instabilities. We experimentally study the sudden build-up of a reverse light field in a laser-driven high-finesse ring cavity filled with ultracold thermal or condensed atoms. While superradiant Rayleigh scattering from atomic clouds is normally only observed at very low temper

Antonio Volta, Oliver Muelken, Alexander Blumen

We study the quantum-mechanical transport on two-dimensional graphs by means of continuous-time quantum walks and analyse the effect of different boundary conditions (BCs). For periodic BCs in both directions, i.e., for tori, the problem can be treated in a large measure analytically. Some of these results carry over to graphs which obey open boundary condit

X. X. Yi, W. Wang

The dissipation effect in a hybrid system is studied in this Letter. The hybrid system is a compound of a classical magnetic particle and a quantum single spin. Two cases are considered. In the first case, we investigate the effect of the dissipative quantum subsystem on the motion of its classical partner. Whereas in the second case we show how the dynamics

Jackie, Shen

A mathematical theory on flocking serves the foundation for several ubiquitous multi-agent phenomena in biology, ecology, sensor networks, economy, as well as social behavior like language emergence and evolution. Directly inspired by the recent fundamental works of Cucker and Smale on the construction and analysis of a generic flocking model, we study the e

A. Re, D. Cora, A. M. Puliti, M. Caselle

Common fragile sites (cfs) are specific regions in the human genome that are particularly prone to genomic instability under conditions of replicative stress. Several investigations support the view that common fragile sites play a role in carcinogenesis. We discuss a genome-wide approach based on graph theory and Gene Ontology vocabulary for the functional

P. Szymczak, Marek Cieplak

Stretching of a protein by a fluid flow is compared to that in a force-clamp apparatus. The comparison is made within a simple topology-based dynamical model of a protein in which the effects of the flow are implemented using Langevin dynamics. We demonstrate that unfolding induced by a uniform flow shows a richer behavior than that in the force clamp. The d

Kwang-Il Goh, Albert-Laszlo Barabasi

The dynamics of a wide range of real systems, from email patterns to earthquakes, display a bursty, intermittent nature, characterized by short timeframes of intensive activity followed by long times of no or reduced activity. The understanding of the origin of such bursty patterns is hindered by the lack of tools to compare different systems using a common

R. Driben, Y. Oz, B. A. Malomed, A. Gubeskys

We propose a way to control solitons in $χ^{(2)}$ (quadratically-nonlinear) systems by means of periodic modulation imposed on the phase-mismatch parameter ("mismatch management", MM). It may be realized in the co-transmission of fundamental-frequency (FF) and second-harmonic (SH) waves in a planar optical waveguide via a long-period modulation of th

I. I. Smolyaninov, Y. J. Hung, C. C. Davis

In this communication we introduce a new design of the magnifying superlens and demonstrate it in the experiment.

Sandor Varro

The reflection and transmission of a few-cycle femtosecond Ti:Sa laser pulse impinging on a metal nano-layer have been analysed. The thickness of the layer was assumed to be of order of 2-10 nm, and the metallic free electrons were represented by a surface current density distributed at the plane boundary of a dielectric substrate. The target studied this wa

Meindert A. van Dijk, Markus Lippitz, Daniel Stolwijk, Michel Orrit

We give a detailed description of a novel method for time-resolved experiments on single non-luminescent nanoparticles. The method is based on the combination of pump-probe spectroscopy and a common-path interferometer. In our interferometer, probe and reference arms are separated in time and polarization by a birefringent crystal. The interferometer, fully

S. Balestra, M. Cozzi, G. Giacomelli, R. Giacomelli

New calibrations of CR39 and Makrofol nuclear track detectors have been obtained using 158 A GeV Pb (82+) and In (49+) ions; a new method for the bulk etch rate determination, using both cone height and base diameter measurements was developed. The CR39 charge resolution based on the etch-pit base area measurement is adequate to identify nuclear fragments in

Bernhard Rothenstein, Stefan Popescu, Ronald P. Gruber

Observers of the uniformly accelerating observers or the observers who make up the system of uniformly accelerating observers reach the same velocity V at different times ti which depends on V and on theirs acceleration gi. Considering a platform that moves with constant velocity V, the observers can land smoothly on it. Their ages and locations in the inert

J. Dudek, J. Dobaczewski, N. Dubray, A. Gozdz

We discuss a point-group-theory based method of searching for new regions of nuclear stability. We illustrate the related strategy with realistic calculations employing the tetrahedral and the octahedral point groups. In particular, several nuclei in the Rare Earth region appear as excellent candidates to study the new mechanism.

I. Filikhin, V. M. Suslov, B. Vlahovic

Configuration space Faddeev equations are applied to describe the Be9Lambda low-lying resonances of the ground band in the alpha+alpha+Lambda cluster model. The method of analytical continuation in coupling constant is used.

E. Bauer

The nonmesonic weak decay of $Λ$ hypernuclei is studied using nuclear matter. We have developed a formalism which gives a microscopic interpretation of the process of emission of particles originated in this decay. More specifically, our scheme provides a unified treatment of $Γ(ΛN \to NN$) and $N_{N}$ ($N_{NN}$), the $Λ$ non-mesonic weak decay widths and th

Sergei A. Voloshin

In this talk I present new STAR results on measurements of integrated elliptic flow at midrapidity in Au+Au and Cu+Cu collisions at $\sqrt{s_{NN}}=$200 and 62 GeV energies. These results have been obtained from azimuthal correlations between particles in the main STAR TPC and two forward TPCs, and are to a large extent free from so-called non-flow correlatio

P. Palaniyandi, M. Lakshmanan

We propose a simple method for secure digital signal transmission by making some modifications in the single-step parameter modulation technique proposed earlier into overcome certain inherent deficiencies. In the modified method, the parameter modulation is effectively regulated or controlled by the chaotic signal obtained from the transmitting chaotic syst

Antonio Degasperis, Sara Lombardo

The Darboux-Dressing Transformations are applied to the Lax pair associated to systems of coupled nonlinear wave equations in the case of boundary values which are appropriate to both bright and dark soliton solutions. The general formalism is set up and the relevant equations are explicitly solved. Several instances of multicomponent wave equations of appli

A. Bistagnino, G. Boffetta, A. Mazzino

Single-particle dispersion in the Bolgiano--Obukhov regime of two-dimensional turbulent convection is investigated. Unlike dispersion in a flow displaying the classical K41 phenomenology, here, the leading contribution to the Lagrangian velocity fluctuations is given by the largest eddies. This implies a linear behavior in time for a typical velocity fluctua

Henrique de A. Gomes

In this work we explore the geometrical interpretation of gauge theories through the formalism of fiber bundles. Moreover, we conduct an investigation in the topology of fiber bundles, providing a proof of the Classification Theorem. In the last chapter we present some applications, such as electromagnetism and generalized Kaluza-Klein Theory.

Pavel Exner, Jiří Lipovský

We discuss resonances for Schrödinger operators on metric graphs which consists of a finite compact part and a finite number of halflines attached to it; the vertex coupling is assumed to be of the $δ$-type or certain modifications of it. Using exterior complex scaling on the graph we show that the resolvent and scattering resonances coincide in this case.

Ovidiu Costin, Percy Deift, Dimitri Gioev

We give a streamlined proof of a quantitative version of a result from [DG1] which is crucial for the proof of universality in the bulk [DG1] and also at the edge [DG2] for orthogonal and symplectic ensembles of random matrices. As a byproduct, this result gives asymptotic information on a certain ratio of the beta=1,2,4 partition functions for log gases.

Huiqiang Jiang

In this paper, we consider a free boundary problem with volume constraint. We show that positive minimizer is locally Lipschitz and the free boundary is analytic away from a singular set with Hausdorff dimension at most $n-8$.

Lahcen Boulanba, M'hamed Eddahbi, Mohamed Mellouk

In this paper we study a class of stochastic partial differential equations in the whole space $\mathbb{R}^{d}$, with arbitrary dimension $d\geq 1$, driven by a Gaussian noise white in time and correlated in space. The differential operator is a fractional derivative operator. We show the existence, uniqueness and Hölder's regularity of the solution. The

Carlos E. Kenig, David J. Rule

We establish optimal L^p bounds for the nontangential maximal function of the gradient of the solution to a second order elliptic operator in divergence form, possibly non-symmetric, with bounded measurable coefficients independent of the vertical variable, on the domain above a Lipschitz graph in the plane, in terms of the L^p norm at the boundary of the ta

Huiqiang Jiang, Wei-Ming Ni

We consider positive solutions of the stationary Gierer-Meinhardt system. Under suitable conditions on the exponents $p,q,r$ and $s$, different types of a priori estimates are obtained, existence and non-existence results of nontrivial solutions are derived, for both positive and zero source production cases.

Fengbo Hang, Huiqiang Jiang

In 1992, P. Poláčik\cite{P2} showed that one could linearly imbed any vector fields into a scalar semi-linear parabolic equation on $Ω$ with Neumann boundary condition provided that there exists a smooth vector field $Φ=(ϕ_{1},...,ϕ_{n}) $ on $\barΩ$ such that \[ \left\{\begin{array} [c]{l}% \operatorname*{rank}(Φ(x) ,\partial_{1}Φ(x) ,...,\partial_{n}Φ(x))

Jean-Marc Derrien

In this note, we prove without using Fourier analysis that the symmetric square integrable random walks in $\Z^{2}$ are recurrent.

Huiqiang Jiang, Wei-Ming Ni

Let $Ω\subset\mathbb{R}^{N}$, $N\geq2$ be a bounded smooth domain and $α>1$. We are interested in the singular elliptic equation% \[ \triangle h=\frac{1}αh^{-α}-p\quad\text{in}Ω\] with Neumann boundary conditions. In this paper, we gave a complete description of all continuous radially symmetric solutions. In particular, we constructed nontrivial smooth solu

Adrian Riskin

We introduce two new measures of the noncordiality of a graph. We then calculate the values of these measures for various families of noncordial graphs. We also determine exactly which of the Möbius ladders are cordial.

Alexander Nabutovsky, Shmuel Weinberger

Define the length of a finite presentation of a group $G$ as the sum of lengths of all relators plus the number of generators. How large can be the $k$th Betti number $b_k(G)=$ rank $H_k(G)$ providing that $G$ has length $\leq N$ and $b_k(G)$ is finite? We prove that for every $k\geq 3$ the maximum $b_k(N)$ of $k$th Betti numbers of all such groups is an ext

Artur Elezi

In an earlier paper we conjectured a relation between the quantum $\mathcal D$-modules of a smooth variety $X$ and the projectivisation of a direct sum of line bundles over it. In this paper we prove the conjecture when $X$ is a complete intersection in a toric variety. We also use the conjecture to show that the relations of the small quantum cohomology rin

Richard G. Clegg

This paper describes, in detail, techniques for measuring the Hurst parameter. Measurements are given on artificial data both in a raw form and corrupted in various ways to check the robustness of the tools in question. Measurements are also given on real data, both new data sets and well-studied data sets. All data and tools used are freely available for do

Jorge A. Leon, Samy Tindel

In this paper we introduce a stochastic integral with respect to the solution X of the fractional heat equation on [0,1], interpreted as a divergence operator. This allows to use the techniques of the Malliavin calculus in order to establish an Itô-type formula for the process X.

Weiping Li, Qingxue Wang

In this paper, we define a new algebro-geometric invariant of 3-manifolds resulting from the Dehn surgery along a hyperbolic knot complement in S^3. We establish a Casson type invariant for these 3-manifolds. In the last section, we explicitly calculate the character variety of the figure-eight knot and discuss some applications, as well as the computation o

Martin Bender

We consider a system of diffusing particles on the real line in a quadratic external potential and with repulsive electrostatic interaction. The empirical measure process is known to converge weakly to a deterministic measure-valued process as the number of particles tends to infinity. Provided the initial fluctuations are small, the rescaled linear statisti

Benoit Kloeckner

A complex filling of a CR manifold is said to be equivariant with respect to a CR action if the action extends to a smooth action by biholomorphisms on the whole filling. Under a noncompactness condition for the action, we describe all equivariant fillings of strongly pseudoconvex CR manifolds of dimension 3. Since the standard sphere is the only compact str

Alexey Sorokin

The paper considers two main results. First one is the uniform bound for strong mixing coefficient of ARCH sequence. Second is the bound for maximum of residual empirical process in the same model. We illustrate their usefulness by proving robustness of two types of estimates (GM and minimum distance).

Weiping Li, Qingxue Wang

In this paper, by using the regulator map of Beilinson-Deligne on a curve, we show that the quantization condition posed by Gukov is true for the SL_2(C) character variety of the hyperbolic knot in S^3. Furthermore, we prove that the corresponding $\mathbb{C}^{*}$-valued closed 1-form is a secondary characteristic class (Chern-Simons) arising from the vanish

Nobuaki Sugimine, Masato Takei

We investigate a limit theorem on traversable length inside semi-cylinder in the 2-dimensional supercritical Bernoulli bond percolation, which gives an extension of Theorem 2 in Grimmett(1981). This type of limit theorems was originally studied for the extinction time for the 1-dimensional contact process on a finite interval in Wagner and Anantharam(2005).

Masayuki Yamasaki

Let $X$ be a connected compact 3-manifold with non-empty boundary. Consider the boundary $M$ of $X\times D^2$. $M$ is a 4-dimensional closed manifold and has the same fundamental group as $X$. Various examples of $X$ are known for which a certain assembly map $A:H_4(X;L)\to L_4(π_1(X))$ is injective. For such an $X$ and any CW-spine $B$ of $X$, there is a $U