Results for "O. Alexandrova"

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Semi-Classical Behavior of the Spectral FunctionFeb 26 2005We study the semi-classical behavior of the spectral function of the Schr\"{o}dinger operator with short range potential. We prove that the spectral function is a semi-classical Fourier integral operator quantizing the forward and backward flow relations ... More
Small Scale Energy Cascade of the Solar Wind TurbulenceOct 03 2007Magnetic fluctuations in the solar wind are distributed according to Kolmogorov's power law $f^{-5/3}$ below the ion cyclotron frequency $f_{ci}$. Above this frequency, the observed steeper power law is usually interpreted in two different ways: a dissipative ... More
Fluid-like dissipation of magnetic turbulence at electron scales in the solar windNov 23 2011The turbulent spectrum of magnetic fluctuations in the solar wind displays a spectral break at ion characteristic scales. At electron scales the spectral shape is not yet completely established. Here, we perform a statistical study of 102 spectra at plasma ... More
Semi-Classical Wavefront Set and Fourier Integral OperatorsJul 27 2004We define and prove some properties of the semi-classical wavefront set. We also define and study semi-classical Fourier integral operators, of which we give a complete characterization. Lastly, we prove a generalization of the semi-classical Egorov's ... More
Structure of the Short Range Amplitude for General Scattering RelationsNov 26 2004We consider scattering by short range perturbations of the semi-classical Laplacian. We prove that when a polynomial bound on the resolvent holds, the scattering amplitude is a semi-classical Fourier integral operator associated to the scattering relation. ... More
[Plasma 2020 Decadal] Multipoint Measurements of the Solar Wind: A Proposed Advance for Studying Magnetized TurbulenceMar 13 2019A multi-institutional, multi-national science team will soon submit a NASA proposal to build a constellation of spacecraft to fly into the near-Earth solar wind in a swarm spanning a multitude of scales in order to obtain critically needed measurements ... More
Methods for characterising microphysical processes in plasmasJun 22 2013Advanced spectral and statistical data analysis techniques have greatly contributed to shaping our understanding of microphysical processes in plasmas. We review some of the main techniques that allow for characterising fluctuation phenomena in geospace ... More
Structure of the Semi-Classical Amplitude for General Scattering RelationsJul 28 2004We consider scattering by general compactly supported semi-classical perturbations of the Euclidean Laplace-Beltrami operator. We show that if the suitably cut-off resolvent of the Hamiltonian quantizes a Lagrangian relation on the product cotangent bundle, ... More
Compressive Coherent Structures at Ion Scales in the Slow Solar WindApr 26 2016We present a study of magnetic field fluctuations, in a slow solar wind stream, close to ion scales, where an increase of the level of magnetic compressibility is observed. Here, the nature of these compressive fluctuations is found to be characterized ... More
[Plasma 2020 Decadal] Disentangling the Spatiotemporal Structure of Turbulence Using Multi-Spacecraft DataMar 13 2019This white paper submitted for 2020 Decadal Assessment of Plasma Science concerns the importance of multi-spacecraft missions to address fundamental questions concerning plasma turbulence. Plasma turbulence is ubiquitous in the universe, and it is responsible ... More
Anisotropy of Solar Wind Turbulence between Ion and Electron ScalesFeb 12 2010Jun 27 2010The anisotropy of turbulence in the fast solar wind, between the ion and electron gyroscales, is directly observed using a multispacecraft analysis technique. Second order structure functions are calculated at different angles to the local magnetic field, ... More
Solar wind turbulent spectrum from MHD to electron scalesDec 14 2009Turbulent spectra of magnetic fluctuations in the free solar wind are studied from MHD to electron scales using Cluster observations. We discuss the problem of the instrumental noise and its influence on the measurements at the electron scales. We confirm ... More
Resolvent and scattering matrix at the maximum of the potentialNov 06 2007We study the microlocal structure of the resolvent of the semi-classical Schrodinger operator with short range potential at an energy which is a unique non-degenerate global maximum of the potential. We prove that it is a semi-classical Fourier integral ... More
Semiclassical scattering amplitude at the maximum point of the potentialApr 12 2007Apr 13 2007We compute the scattering amplitude for Schr\"odinger operators at a critical energy level, corresponding to the maximum point of the potential. We follow the wrok of Robert and Tamura, '89, using Isozaki and Kitada's representation formula for the scattering ... More
A local approach to the study of energy transfers in incompressible magnetohydrodynamic turbulenceDec 14 2018We present a local approach to the study of scale-to-scale energy transfers in magnetohydrodynamic (MHD) turbulence. This approach is based on performing local averages of the physical fields, which amounts to filtering scales smaller than some parameter ... More
Simplices with equiareal facesSep 10 2009We study simplices with equiareal faces in the Euclidean 3-space by means of elementary geometry. We present an unexpectedly simple proof of the fact that, if such a simplex is non-degenerate, than every two of its faces are congruent. We show also that ... More
Spectra and anisotropy of magnetic fluctuations in the Earth's magnetosheath: Cluster observationsOct 03 2008We investigate the spectral shape, the anisotropy of the wave vector distributions and the anisotropy of the amplitudes of the magnetic fluctuations in the Earth's magnetosheath within a broad range of frequencies. We present the first observations of ... More
Coherent events and spectral shape at ion kinetic scales in the fast solar wind turbulenceFeb 23 2016In this paper we investigate spectral and phase coherence properties of magnetic fluctuations in the vicinity of the spectral transition from large, magnetohydrodynamic (MHD) to sub-ion scales using in-situ measurements of the Wind spacecraft in a fast ... More
Anisotropies of the magnetic field fluctuations at kinetic scales in the solar wind : Cluster observationsOct 06 2017We present the first statistical study of the anisotropy of the magnetic field turbulence in the solar wind between 1 and 200Hz, i.e. from proton to sub-electron scales. We consider 93 10-minute intervals of Cluster/STAFF measurements. We find that the ... More
Magnetospheric Multiscale Observation of Kinetic Signatures in the Alfvén VortexJan 12 2019Alfv\'en vortex is a multi-scale nonlinear structure which contributes to intermittency of turbulence. Despite previous explorations mostly on the spatial properties of the Alfv\'en vortex (i.e., scale, orientation, and motion), the plasma characteristics ... More
Solar wind turbulent spectrum at plasma kinetic scalesDec 03 2012The description of the turbulent spectrum of magnetic fluctuations in the solar wind in the kinetic range of scales is not yet completely established. Here, we perform a statistical study of 100 spectra measured by the STAFF instrument on the Cluster ... More
Fluid theory of coherent magnetic vortices in high-beta space plasmasMay 08 2017Jun 11 2018In-situ observations in the Earth's and Saturn's magnetosheaths and in the solar wind reveal the presence of Alfv\'en vortices as intermittent structures in the range of scales from tens to several ion scales. These magnetic vortices appear compressible ... More
Observation of an MHD Alfvén vortex in the slow solar windFeb 24 2016In the solar wind, magnetic field power spectra usually show several power-laws. In this paper, magnetic field data from the Cluster mission during an undisturbed interval of slow solar wind is analyzed at 0.28Hz, near the spectral break point between ... More
Gyrokinetic theory of magnetic structures in high-beta plasmas of the Earths magnetopause and of the slow solar windMay 08 2017Nonlinear effects of the trapping of resonant particles by the combined action of the electric field and the magnetic mirror force is studied using a gyrokinetic description that includes the finite Larmor radius effects. A general nonlinear solution ... More
3D Anisotropy of Solar Wind Turbulence, Tubes, or Ribbons?Feb 27 2018Jan 30 2019We study the anisotropy with respect to the local magnetic field of turbulent magnetic fluctuations at magnetofluid scales in the solar wind. Previous measurements in the fast solar wind obtained axisymmetric anisotropy, despite that the analysis method ... More
Solar Wind Turbulence and the Role of Ion InstabilitiesJun 22 2013Solar wind is probably the best laboratory to study turbulence in astrophysical plasmas. In addition to the presence of magnetic field, the differences with neutral fluid isotropic turbulence are: weakness of collisional dissipation and presence of several ... More
Variability Of The Magnetic Field Power Spectrum In The Solar Wind At Electron ScalesOct 13 2017At the electron scales the power spectrum of solar-wind magnetic fluctuations can be highly variable and the dissipation mechanisms of the magnetic energy into the various particle species is under debate. In this paper we investigate data from the Cluster ... More
Universality of solar wind turbulent spectrum from MHD to electron scalesJun 17 2009Sep 01 2009In order to investigate the universality of magnetic turbulence in space plasmas we analyze seven time periods in the free solar wind of different origin, slow or fast, and under different plasma conditions. The orientation of magnetic field to the flow ... More
Supercritical instability of Dirac electrons in the field of two oppositely charged nucleiSep 29 2016The Dirac equation for an electron in a finite dipole potential has been studied within the method of linear combination of atomic orbitals (LCAO). The Coulomb potential of the nuclei that compose a dipole is regularized, by considering the finite nuclear ... More
Can a gravitational wave and a magnetic monopole coexist?Aug 06 1997Nov 17 1997We investigate the behavior of small perturbations around the Kaluza-Klein monopole in the five dimensional space-time. We find that the even parity gravitational wave does not propagate in the five dimensional space-time with Kaluza-Klein monopole provided ... More
Quantum singularities in (2+1) dimensional matter coupled black hole spacetimesApr 15 2010Sep 16 2010Quantum singularities considered in the 3D BTZ spacetime by Pitelli and Letelier (Phys. Rev. D77: 124030, 2008) is extended to charged BTZ and 3D Einstein-Maxwell-dilaton gravity spacetimes. The occurence of naked singularities in the Einstein-Maxwell ... More
On Groups with a Supercomplemented SubgroupOct 05 2007Groups, in which every subgroup containing some fixed primary cyclic subgroup has a complement, are investigated.
Superhard Phases of Simple Substances and Binary Compounds of the B-C-N-O System: from Diamond to the Latest Results (a Review)Jan 15 2011The basic known and hypothetic one- and two-element phases of the B-C-N-O system (both superhard phases having diamond and boron structures and precursors to synthesize them) are described. The attention has been given to the structure, basic mechanical ... More
On self-similar solutions of the vortex filament equationMar 05 2019We study self-similar solutions of the binormal curvature flow which governs the evolution of vortex filaments and is equivalent to the Landau-Lifshitz equation. The corresponding dynamics is described by the real solutions of $\sigma$-Painlev\'{e} IV ... More
Condensation temperature of interacting Bose gases with and without disorderApr 24 2006The momentum-shell renormalization group (RG) is used to study the condensation of interacting Bose gases without and with disorder. First of all, for the homogeneous disorder-free Bose gas the interaction-induced shifts in the critical temperature and ... More
Migdal's model and holographyJan 23 2007May 29 2007Migdal's model on the spectrum of vector mesons is reassessed. We discuss how its departure from a Pade approximant is closely linked to the issue of quark-hadron duality breakdown. We also show that Migdal's model is not truly a model of large-Nc QCD. ... More
Photospheric processes and magnetic flux tubesSep 01 2007In the first part of these lecture notes, new high-resolution observations of small-scale magnetic flux concentrations are presented and compared to results from new three-dimensional magnetohydrodynamic simulations. Special attention is paid to the physics ... More
On Witten's global anomaly for higher SU(2) representationsSep 02 2002The spectral flow of the overlap operator is computed numerically along a path connecting two gauge fields which differ by a topologically non-trivial gauge transformation. The calculation is performed for SU(2) in the 3/2 and 5/2 representation. An even-odd ... More
Study of predominant hadronic modes of $τ$-lepton using a Monte Carlo generator TAUOLAJun 28 2015Aug 22 2015TAUOLA is a Monte Carlo generator dedicated to generating tau-lepton decays and it is used in the analysis of experimental data both at B-factories and LHC. TAUOLA is a long-term project that started in the 90's and has been under development up to now. ... More
Evolution of electric-field-induced quasibound states and resonances in one-dimensional open quantum systemsNov 01 2016A comparative analysis of three different time-independent approaches to studying open quantum structures in uniform electric field $\mathscr{E}$ was performed using the example of one-dimensional attractive or repulsive $\delta$-potential and surface ... More
Three Key Tests to GravityJun 20 2003Three presumably unrelated open questions concerning gravity and the structure of the Universe are here discussed: 1) To which extent is Lorentz invariance an exact symmetry ? 2) What is the equation of state of the Universe ? 3) What is the origin of ... More
Is Minisuperspace Quantum Gravity Reliable?Jan 27 2001Feb 13 2001We study a minisuperspace quantum cosmology for a 2+1 dimensional de Sitter universe and find the wave function both exactly and in WKB approximation. Then we extend the model to a canonically quantized field theory for quantum gravity, i.e., a midisuperspace, ... More
Diagnostic of stellar magnetic fields with cumulative circular polarisation profilesMay 27 2015Information about stellar magnetic field topologies is obtained primarily from high-resolution circular polarisation (Stokes $V$) observations. Due to their generally complex morphologies, the stellar Stokes $V$ profiles are usually interpreted with elaborate ... More
Variation of the line profile moments for stars pulsating in distorted oblique non-radial modesMar 21 2005We derive expressions and develop a numerical technique for the analysis of the line profile moment variations for stars pulsating in oblique non-radial modes. This represents an extension of the widely used spectroscopic moment mode identification method ... More
Social Behaviour of Agents: Capital Markets and Their Small PerturbationsMay 11 2005We study social behaviour of agents on capital markets when these are perturbed by small perturbations. We use the mean field method. Social behaviour of agents on capital markets is described: volatility of the market, aversion constant and equilibrium ... More
Landau theory of 180 degrees domain walls in BaTiO3 type ferroelectric particles: microcomposite materialsApr 27 2005Apr 27 2005The Landau theory of 180 degrees domain walls in BaTiO3 type ferroelectric particles is presented. Results of exact description of domain walls in bulk enabled us to formulate variational approach to theory of domain walls in corresponding small particles. ... More
Percolation thresholds on planar Euclidean relative neighborhood graphsJan 29 2013In the presented article, statistical properties regarding the topology and standard percolation on relative neighborhood graphs (RNGs) for planar sets of points, considering the Euclidean metric, are put under scrutiny. RNGs belong to the family of ``proximity ... More
Post-Riemannian Spacetimes Admit a Causal StructureJun 22 1997Apr 20 1999Paper withdrawn due to conceptual mistakes. A corrected version will soon be available at the gr-qc archive.
Theory of the Robin quantum wall in a linear potential. I. Energy spectrum, polarization and quantum-information measuresMay 10 2016Information-theoretical concepts are employed for the analysis of the interplay between a transverse electric field $\mathscr{E}$ applied to a one-dimensional surface and Robin boundary condition (BC), which with the help of the extrapolation length $\Lambda$ ... More
Comparative analysis of electric field influence on the quantum wells with different boundary conditions. I. Energy spectrum, quantum information entropy and polarizationFeb 10 2015Apr 07 2015Analytical solutions of the Schr\"{o}dinger equation for the one-dimensional quantum well with all possible permutations of the Dirichlet and Neumann boundary conditions (BCs) in perpendicular to the interfaces uniform electric field $\mathscr{E}$ are ... More
On Borel summation and Stokes phenomena of nonlinear differential systemsAug 16 2006In this paper we study analytic (linear or) nonlinear systems of ordinary differential equations, at an irregular singularity of rank one, under nonresonance conditions. It is shown that the formal asymptotic exponential series solutions (transseries ... More
Singularity barriers and Borel plane analytic properties of 1+ difference equationsAug 12 2006The paper addresses generalized Borel summability of ``$1^+$'' difference equations in ``critical time''. We show that the Borel transform $Y$ of a prototypical such equation is analytic and exponentially bounded for $\Re(p)<1$ but there is no analytic ... More
What mediates the longest correlation length in the QCD plasma?Jan 17 2003When thermal QCD crosses the critical temperature from below, its pressure density rises drastically, consistent with the picture of deconfinement and the release of partons as light degrees of freedom. On the other hand, the concept of partons is a perturbative ... More
Approximations of the self-similar solution for blastwave in a medium with power-law density variationFeb 04 2000Approximations of the Sedov self-similar solution for a strong point explosion in a medium with the power-law density distribution \rho^o\propto r^{-m} are reviewed and their accuracy are analyzed. Taylor approximation is extended to cases m\neq 0. Two ... More
Determination of alpha_S at 500 GeV from Event Shapes and Jet RatesDec 22 1999The potential of the TESLA linear e+e- collider to determine the strong coupling constant, alpha_S, at 500 GeV is investigated. Experimental complications due to background from W- and Z-pairs, top-production, initial state photon radiation and from beamstrahlung ... More
Note on the magnetotransport in the normal state of high-Tc cupratesJun 02 2000Theories of the magnetotransport, based on the quasipartricle of the Fermi-liquid, in the normal state of high-Tc cuprate superconductors, are critically examined and the necessity of the collective transport theory beyond the quasiparticle is discussed. ... More
Note on the exponent puzzle of the Anderson-Mott transitionMar 30 2007The exponent puzzle of the Anderson-Mott transition is discussed on the basis of a duality model for strongly correlated electrons.
Note on the Spin-Spin Relaxation Time in High-Tc Cuprate SuperconductorsNov 16 2000Recent experiments on the spin-spin relaxation time in high-Tc cuprate superconductors are discussed on the basis of the BCS-RPA theory.
On the Quantum Inverse Problem for the Closed Toda ChainApr 07 2003We reconstruct the canonical operators $p_i,q_i$ of the quantum closed Toda chain in terms of Sklyanin's separated variables.
Upper functions for $L_p$-norm of gaussian random fieldsNov 20 2013In this paper we are interested in finding upper functions for a collection of random variables $\big\{\big\|\xi_{\vec{h}}\big\|_p, \vec{h}\in\mathrm{H}\big\}, 1\leq p<\infty$. Here $\xi_{\vec{h}}(x), x\in(-b,b)^d, d\geq 1$ is a kernel-type gaussian random ... More
Systematic effects in apparent proper motion of radio sourcesMay 08 2008The galactocentric rotation of the Solar system generates the systematic effect in proper motions known as 'secular aberration drift'. This tiny effect (about five microseconds per year) in the quasar proper motion can be measured by VLBI. However, the ... More
Analytic Form Factors of Hydrogenlike Atoms for Discrete-Continuum Transitions. II. General CaseJan 07 2002Mar 05 2003A general formula for bound-continuous transition form factors is derived. It is shown that these form factors can be represented in the form of finite sum of terms with simple analytical structure.
Modeling and optimization of the antenna system with focal plane array for the new generation radio telescopes with wide field of viewFeb 15 2016The model of the reflector antenna system with focal plane array, low-noise amplifier and beamformer is developed in the work. The beamformer strategy is suggested to reduce the receiving sensitivity ripple inside field of view of the telescope, while ... More
Higher-order corrections to the splitting functions from differential equations in QCDJan 14 2016We report on the status an ab initio computation of the time-like splitting functions at next-to-next-to-leading order in QCD. Time-like splitting functions govern the collinear kinematics of inclusive hadron production in $e^+e^-$ annihilation and the ... More
The Thom Class and Localization of SUSY QM Generating FunctionalNov 13 2001We demonstrate the usage of explicit form of the Thom class found by Mathai and Quillen for the definition of generating functional of a simple supersymmetric quantum mechanical model.
Limit Theorem for Sums of Random ProductsOct 11 2002We study a generalization of the Random Energy Model to the case when the number of exponential factors varies at random. Also a relation between REM and the Erd"os-R'enyi limit theorem for maximums of partial sums is considered.
A New Basis Function Approach to 't Hooft EquationMar 13 2000We present the new basis functions to investigate the 't Hooft equation, the lowest order mesonic Light-Front Tamm-Dancoff equation for $\rm SU(N_C)$ gauge theories. We find the wave function can be well approximated by new basis functions and obtain ... More
On ultrametric-preserving functionsFeb 23 2019Several new characterizations of pseudoultrametric spaces and ultrametric spaces are found. In particular, a dual form of Pongsriiam-Termwuttipong characterization of the ultrametric-preserving functions is described.
The combinatorial geometry of stresses in frameworksDec 08 2015In this paper we formulate and prove necessary and sufficient geometric conditions for existence of generic tensegrities in the plane for arbitrary graphs. The conditions are written in terms of "meet-join" relations for the configuration spaces of fixed ... More
Hydrodynamic stability of rotationally supported flows: Linear and nonlinear 2D shearing box resultsApr 01 2004Aug 31 2004We present here both analytical and numerical results of hydrodynamic stability investigations of rotationally supported circumstellar flows using the shearing box formalism. Asymptotic scaling arguments justifying the shearing box approximation are systematically ... More
CP violation in production of neutralinos in e+ e- collisionsNov 13 2003We propose T-odd and CP-odd odd asymmetries in order to analyze the impact of CP violating phases in neutralino production and subsequent leptonic two-body decays. We present numerical results of these asymmetries and of the cross sections for complex ... More
Stochastic Electrochemical KineticsAug 26 2016Sep 18 2016A new tool for modeling electrochemical kinetics is presented. An extension of the Stochastic Simulation Algorithm framework to electrochemical systems is proposed. The physical justifications and constraints for the derivation of a chemical master equation ... More
Lieux de dégénérescence (Degeneracy loci)Dec 11 1998We prove Lefschetz type theorems for cohomology groups and Picard groups of degeneracy loci for vector bundle maps. We also treat the case of antisymmetric maps.
The universality class of the continuous phase transition in the 2D "Touch and Stop" cluster growth percolation modelNov 02 2012We consider the "Touch and Stop" cluster growth percolation (CGP) model on the two dimensional square lattice. A key-parameter in the model is the fraction p of occupied "seed" sites that act as nucleation centers from which a particular cluster growth ... More
Potential-density pairs and vertical tilt of the stellar velocity ellipsoidApr 07 2009We define new potential-density pairs and examine the impact of the potential flattening on the vertical velocity ellipsoid tilt, $\delta$. By means of numerical integrations and analytical calculations, we estimate $\delta$ in a variety of galactic potentials. ... More
Integrable Many-Body Systems of Calogero-Moser-Sutherland Type in High DimensionOct 21 1995Nov 09 1995A new series of integrable cases of the many-body problem in many-dimensional spaces is found. That series appears as a part of the larger series of integrable problems, which are in 1-1 correspondence with Krichever-Novikov algebras of affine type (that ... More
Post-Riemannian Merger of Yang-Mills Interactions with GravityAug 17 2000Sep 05 2001We show that a post-Riemannian spacetime can accommodate an internal symmetry structure of the Yang-Mills prototype in such a way that the internal symmetry becomes an integral part of the spacetime itself. The construction encrusts the internal degrees ... More
Theory of the Robin quantum wall in a linear potential. II. Thermodynamic propertiesMay 10 2016A theoretical analysis of the thermodynamic properties of the Robin wall characterized by the extrapolation length $\Lambda$ in the electric field $\mathscr{E}$ that pushes the particle to the surface is presented both in the canonical and two grand canonical ... More
Mass transfer from the donor of GRS 1915+105Apr 09 2002Apr 18 2002A scenario for a periodic filling and emptying of the accretion disc of the microquasar GRS 1915+105 is proposed, by computing the mass transfer rate from the evolving low mass red giant donor (Greiner at al. 2001) and comparing it with the observed accretion ... More
A Phenomenological Description of the Non-Fermi-Liquid Phase of MnSiApr 30 2004Aug 10 2004In order to understand the non-Fermi-liquid behavior of MnSi under pressure we propose a scenario on the basis of the multispiral state of the magnetic moment. This state can describe the recent critical experiment of the Bragg sphere in the neutron scattering ... More
Magnetotransport Scaling in Anomalous Metallic Phase near the Mott TransitionMar 21 2001The Hall angle in the doped V_2O_3 is discussed on the basis of an extended Ginzburg-Landau theory of spin fluctuations. A spinon-like collective transport process beyond the ordinary quasiparticle transport theory is necessary to understand the experiment. ... More
Combined QCD analysis of e^+ e^- data at sqrt(s) = 14 to 172 GeVAug 26 1997A study of the energy dependence of event shape observables is presented. The strong coupling constant \alpha_s has been determined from the mean values of six event shape observables. Power corrections, employed for the measurement of \alpha_s, have ... More
$\mathcal{PT}$ Symmetric Hamiltonian Model and Dirac Equation in 1+1 dimensionsJan 02 2013In this article, we have introduced a $\mathcal{PT}$ symmetric non-Hermitian Hamiltonian model which is given as $\hat{\mathcal{H}}=\omega (\hat{b}^{\dag}\hat{b}+1/2)+ \alpha (\hat{b}^{2}-(\hat{b}^{\dag})^{2})$ where $\omega$ and $\alpha$ are real constants, ... More
$su(1,1)\simeq so(2,1)$ Lie Algebraic Extensions of the Mie-type Interactions with Positive Constant CurvatureJan 02 2013The Schr\"{o}dinger equation in three dimensional space with constant positive curvature is studied for the Mie potential. Using analytic polynomial solutions, we have obtained whole spectrum of the corresponding system. With the aid of factorization ... More
LHCf: physics results on forward particle production at LHCOct 14 2013The LHCf experiment is dedicated to the measurement of very forward particle production in the high energy hadron-hadron collisions at LHC, with the aim of improving the cosmic-ray air shower developments models. The detector has taken data in p-p collisions ... More
Revival of Single-Particle Transport Theory for the Normal State of High-Tc Superconductors: I. Relaxation-Time ApproximationApr 24 2012Jan 17 2014How the fluctuation-exchange (FLEX) approximation and the Fermi-liquid theory fail to explain the anomalous behavior of the Hall coefficient in the normal state of high-Tc superconductors is clarified.
Systematic effects in the radio source proper motionJun 26 2009Some models of the expanding Universe predict that the astrometric proper motion of distant radio sources embedded in space-time are non-zero as radial distance from observer to the source grows. Systematic effects due to this proper motion can even increase ... More
High Moments of Large Wigner Random Matrices and Asymptotic Properties of the Spectral NormJul 21 2009Nov 21 2011We consider an ensemble of nxn real symmetric random matrices A whose entries are determined by independent identically distributed random variables that have symmetric probability distribution. Assuming that the moment 12+2delta of these random variables ... More
A class of even walks and divergence of high moments of large Wigner random matricesMay 18 2010May 19 2010We study high moments of truncated Wigner nxn random matrices by using their representation as the sums over the set W of weighted even closed walks. We construct the subset W' of W such that the corresponding sum diverges in the limit of large n and ... More
Decoherence via coupling to a finite quantum heat bathAug 10 2013Feb 05 2014Decoherence of a quantum state coupled to an exterior environment is at the foundation of our understanding of the emergence of classical behavior from the quantum world, but how does it emerge in a finite closed quantum system? Here this is studied by ... More
Bandwidths Statistics from the Eigenvalue Moments for Harper-Hofstadter ProblemOct 15 1999I propose a method for studying the product of bandwidths for the Harper-Hofstader model. This method requires knowledge of the moments of the midband energies. I conjectured a general formula for these moments. I computed the asymptotic representation ... More
Quantum information measures of the Aharonov-Bohm ring in uniform magnetic fieldsDec 25 2018Shannon quantum information entropies $S_{\rho,\gamma}$, Fisher informations $I_{\rho,\gamma}$, Onicescu energies $O_{\rho,\gamma}$ and complexities $e^SO$ are calculated both in position (subscript $\rho$) and momentum ($\gamma$) spaces for azimuthally ... More
Asymptotic behavior of two-terminal series-parallel networksJul 02 1997This paper discusses the enumeration of two-terminal series-parallel networks, i.e. the number of electrical networks built with n identical elements connected in series or parallel with two-terminal nodes. They frequently occur in applied probability ... More
Statistics of delta peaks in the spectral density of large random treesJan 23 2003We present an analysis of the spectral density of the adjacency matrix of large random trees. We show that there is an infinity of delta peaks at all real numbers which are eigenvalues of finite trees. By exact enumerations and Monte-Carlo simulations, ... More
Une methode Monte-Carlo pour les meandres sur ordinateur paralleleOct 01 1999Pour modeliser le repliement compact d'un polymere, on etudie la statistique des meandres, definis comme configurations d'un circuit automobile traversant n fois une riviere. Grace a une methode Monte-Carlo adaptee a un ordinateur massivement parallele, ... More
Estimates for moments of random matrices with Gaussian elementsJul 22 2005Jul 23 2006We describe an elementary method to get non-asymptotic estimates for the moments of Hermitian random matrices whose elements are Gaussian independent random variables. As the basic example, we consider the GUE matrices. Immediate applications include ... More
Explicit Wodzicki excision in cyclic homologyNov 17 2013Oct 21 2014Assuming local one-sided units exist, I give an elementary proof of Wodzicki excision for cyclic homology. The proof is also constructive and provides an explicit inverse excision map. As far as I know, the latter is new.
Study of ultra-high gradient acceleration in carbon nanotube arraysMay 03 2018Solid-state based wakefield acceleration of charged particles was previously proposed to obtain extremely high gradients on the order of 1-10 TeV/m. In recent years the possibility of using either metallic or carbon nanotube structures is attracting new ... More
Whistler mode waves and the electron heat flux in the solar wind: Cluster observationsOct 22 2014The nature of the magnetic field fluctuations in the solar wind between the ion and electron scales is still under debate. Using the Cluster/STAFF instrument, we make a survey of the power spectral density and of the polarization of these fluctuations ... More
A bijection which implies Melzer's polynomial identities: the $χ_{1,1}^{(p,p+1)}$ caseJan 20 1995We obtain a bijection between certain lattice paths and partitions. This implies a proof of polynomial identities conjectured by Melzer. In a limit, these identities reduce to Rogers--Ramanujan-type identities for the $\chi_{1,1}^{(p,p+1)}(q)$ Virasoro ... More