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Coulomb Blockade from the Shell of an InP-InAs Core-Shell Nanowire with a Triangular Cross SectionJan 28 2019We report on growth of InP-InAs core-shell nanowires and demonstration of the formation of single quantum structures, which show Coulomb blockade effect, over entire lengths of the nanowires. The core-shell nanowires are grown by a selective area growth ... More

Measurements of strain and bandgap of coherently epitaxially grown wurtzite InAsP-InP core-shell nanowiresApr 12 2019We report on experimental determination of the strain and bandgap of InAsP in epitaxially grown InAsP-InP core-shell nanowires. The core-shell nanowires are grown via metal-organic vapor phase epitaxy. The as-grown nanowires are characterized by transmission ... More

Analysis of strain and stacking faults in single nanowires using Bragg coherent diffraction imagingOct 28 2009Jan 21 2010Coherent diffraction imaging (CDI) on Bragg reflections is a promising technique for the study of three-dimensional (3D) composition and strain fields in nanostructures, which can be recovered directly from the coherent diffraction data recorded on single ... More

Combinatorial Differential FormsMay 09 2000We extend to a scheme-theoretic context the notion of a combinatorial differential form, due to A.Kock in the framework of synthetic differential geometry. We show that group-valued combinatorial forms on a scheme may be identified, under very general ... More

A universal coefficient theorem for Gauss's LemmaSep 27 2012Oct 24 2012We prove a version of Gauss's Lemma. It recursively constructs polynomials {c_k} for k=0,1,...,m+n, in Z[a_i,A_i,b_j,B_j] for i=0,...,m, and j=0,1,...,n, having degree at most (m+n choose m) in each of the four variable sets, such that whenever {A_i},{B_j},{C_k} ... More

Differential Geometry of GerbesJun 11 2001Aug 10 2003We define in a global manner the notion of a connective structure for a gerbe on a space X. When the gerbe is endowed with trivializing data with respect to an open cover of X, we describe this connective structure in two separate ways, which extend from ... More

Rotation Measure Synthesis of Galactic Polarized Emission with the DRAO 26-m TelescopeFeb 11 2010Feb 23 2010Radio polarimetry at decimetre wavelengths is the principal source of information on the Galactic magnetic field. The diffuse polarized emission is strongly influenced by Faraday rotation in the magneto-ionic medium and rotation measure is the prime quantity ... More

RHyTHM: A Randomized Hybrid Scheme To Hide in the Mobile CrowdDec 09 2017Any on-demand pseudonym acquisition strategy is problematic should the connectivity to the credential management infrastructure be intermittent. If a vehicle runs out of pseudonyms with no connectivity to refill its pseudonym pool, one solution is the ... More

Aging associated domain evolution in the orthorhombic phase of <001> textured (K0.5Na0.5)Nb0.97Sb0.03O3 ceramicsDec 15 2011An aging effect due to a domain evolution in (K0.5,Na0.5)Nb0.97Sb0.03O3 <001> textured ceramics was investigated by piezoresponse force microscopy. We find that such an aging effect is pronounced in the orthorhombic single phase field. A more uniform ... More

Templated Grain Growth in Macroporous MaterialsJun 30 2015We demonstrate a facile method to produce crystallographically textured, macroporous materials using a combination of modified ice templating and templated grain growth (TGG). The process is demonstrated on alumina and the lead-free piezoelectric material ... More

Multiple exciton generation in nano-crystals revisited: Consistent calculation of the yield based on pump-probe spectroscopyFeb 27 2013Multiple exciton generation (MEG) is a process in which more than one exciton is generated upon the absorption of a high energy photon, typically higher than two times the band gap, in semiconductor nanocrystals. It can be observed experimentally using ... More

Three-Dimensional Grain Boundary Spectroscopy in Transparent High Power Ceramic Laser MaterialsMar 24 2008Using confocal Raman and fluorescence spectroscopic imaging in 3-dimensions, we show direct evidence for Nd3+-Nd3+ interactions across grain boundaries (GBs) in Nd3+:YAG laser ceramics. It is clearly shown that Nd3+ segregation takes place at GBs leading ... More

A Silver Anniversary Observation of the X-ray Emitting SN1978K in NGC 1313Jul 18 2007We describe the results of a 2003 Chandra ACIS-I observation of SN1978K. The spectrum shows little flux below 0.6 keV, in contrast to the 2002 ACIS-S observation that showed flux to 0.4 keV. Fitting the ACIS-I spectrum alone leads to two solutions depending ... More

QED Electrical Conductivity using the 2PI Effective ActionMay 01 2007In this article we calculate the electrical conductivity in QED using the 2PI effective action. We use a modified version of the usual 2PI effective action which is defined with respect to self-consistent solutions of the 2-point functions. We show that ... More

Examining Tatooine: Atmospheric Models of Neptune-Like Circumbinary PlanetsMay 27 2016Circumbinary planets experience a time varying irradiation pattern as they orbit their two host stars. In this work, we present the first detailed study of the atmospheric effects of this irradiation pattern on known and hypothetical gaseous circumbinary ... More

Monolayer Solid Helium-4 Clusters on GraphiteNov 16 1998In order to resolve the controversy about the low density region of the phase diagram of the 4He monolayer on graphite, we have undertaken a path integral Monte Carlo study of the system. We provide direct evidence that the low density monolayer possesses ... More

Baryon resonances from chiral coupled-channel dynamicsJan 25 2005We discuss the formation of s- and d-wave baryon resonances as predicted by the chiral SU(3) symmetry of QCD. Based on the leading order term of the chiral Lagrangian a rich spectrum of molecules is generated, owing to final-state interactions. The spectrum ... More

On charm baryon resonances and chiral symmetryJul 18 2003Sep 16 2003We study heavy-light baryon resonances with quantum numbers J^P=1/2^- in terms of the non-linear chiral SU(3) Lagrangian. Within the chi-BS(3) approach a parameter-free leading order prediction is obtained for the scattering of Goldstone bosons off heavy-light ... More

On heavy-light meson resonances and chiral symmetryJul 09 2003Aug 13 2003We study heavy-light meson resonances with quantum numbers J^P=0^+ and J^P=1^+ in terms of the non-linear chiral SU(3) Lagrangian. At leading order a parameter-free prediction is obtained for the scattering of Goldstone bosons off heavy-light pseudo-scalar ... More

Temperature effects in pulsating superfluid neutron starsMay 20 2011We study the effects of finite stellar temperatures on the oscillations of superfluid neutron stars. The importance of these effects is illustrated with a simple example of a radially pulsating general relativistic star. Two main effects are taken into ... More

Bulk viscosity of superfluid hyperon starsJun 30 2008We calculated bulk viscosity due to non-equilibrium weak processes in superfluid nucleon-hyperon matter of neutron stars. For that, the dissipative relativistic hydrodynamics, formulated in paper [1] for superfluid mixtures, was extended to the case when ... More

Compactness of matrix operators on some sequence spaces derived by Fibonacci numbersAug 31 2013In this paper, we apply the Hausdorff measure of noncompactness to obtain the necessary and sufficient conditions for certain matrix operators on the Fibonacci difference sequence spaces l_{p}(F) and l_{infinite}(F) to be compact, where 1<=p<infinite. ... More

Decoupling of superfluid and normal modes in pulsating neutron starsJul 16 2010Jan 18 2012We show that equations governing pulsations of superfluid neutron stars can be splitted into two sets of weakly coupled equations, one describing the superfluid modes and another one -- the normal modes. The coupling parameter s is small, |s| ~ 0.01-0.05, ... More

The neutrino emission due to plasmon decay and neutrino luminosity of white dwarfsAug 15 2007One of the effective mechanisms of neutrino energy losses in red giants, presupernovae and in the cores of white dwarfs is the emission of neutrino-antineutrino pairs in the process of plasmon decay. In this paper, we numerically calculate the emissivity ... More

On meson resonances and chiral symmetryJul 09 2003Nov 21 2003We study meson resonances with quantum numbers J^P=1^+ in terms of the chiral SU(3) Lagrangian. At leading order a parameter-free prediction is obtained for the scattering of Goldstone bosons off vector mesons with J^P=1^- once we insist on approximate ... More

Leading Order QCD Shear Viscosity from the 3PI Effective ActionJun 05 2009In this article we calculate the leading order shear viscosity in QCD using the resummed 3PI effective action. We work to 3-loop order in the effective action. We show that the integral equations that resum the pinching and collinear contributions are ... More

Leading Order QED Electrical Conductivity from the 3PI Effective ActionSep 05 2007In this article we study the electrical conductivity in QED using the resummed 3PI effective action. We work to 3-loop order in the effective action. We show that the resulting expression for the conductivity is explicitly gauge invariant, and that the ... More

Chiral dynamics for exotic open-charm resonancesJun 01 2004We review the open-charm spectrum of chiral excitations in QCD. At leading order in a chiral expansion a parameter-free prediction is obtained for the coupled-channel scattering of Goldstone bosons off open-charm mesons and baryons with 0^-,1^- and {1/2}^+ ... More

Chiral symmetry and resonances in QCDFeb 25 2004We study the formation of resonances in terms of the chiral SU(3) Lagrangian. At leading order parameter-free predictions are obtained for the scattering of Goldstone bosons off any hadron once we insist on approximate crossing symmetry of the unitarized ... More

The $χ$-BS(3) approachOct 18 2001We present the results of the $\chi$-BS(3) approach demonstrating that a combined chiral and 1/N_c expansion of the Bethe-Salpeter interaction kernel leads to a good description of the kaon-nucleon, antikaon-nucleon and pion-nucleon scattering data typically ... More

Velocity-dependent energy gaps and dynamics of superfluid neutron starsJun 28 2012Nov 05 2012We show that suppression of the baryon energy gaps, caused by the relative motion of superfluid and normal liquid components, can substantially influence dynamical properties and evolution of neutron stars. This effect has been previously ignored in the ... More

Screening in gated bilayer graphene via variational calculusMar 29 2010We analyze the response of bilayer graphene to an external transverse electric field using a variational method. A previous attempt to do so in a recent paper by Falkovsky [Phys. Rev. B 80, 113413 (2009)] is shown to be flawed. Our calculation reaffirms ... More

$Λ(1520)$ at finite densityDec 30 2005We study the decay channels of the $\Lambda(1520)$ in a nuclear medium and find a sizable change - of the order of factor five - of the width of this hyperon at normal nuclear matter density. The mass shift of the $\Lambda(1520)$ is moderate.

Modular operadsAug 17 1994Oct 31 1996Modular operads are a special type of operad: in fact, they bear the same relationship to operads that graphs do to trees (i.e. simply connected graphs). One of the basic examples of a modular operad is the collection of Deligne-Mumford-Knudsen moduli ... More

On the classical dynamics of billiards on the sphereMar 23 1999We study the classical motion in bidimensional polygonal billiards on the sphere. In particular we investigate the dynamics in tiling and generic rational and irrational equilateral triangles. Unlike the plane or the negative curvature cases we obtain ... More

The hypercentral Constituent Quark Model and its application to baryon propertiesJan 15 2015Feb 13 2015The hypercentral Constituent Quark Model (hCQM) for the baryon structure is reviewed and its applications are systematically discussed. The model is based on a simple form of the quark potential, which contains a Coulomb-like interaction and a confinement, ... More

The B_{s0} meson and the B_{s0}B K coupling from QCD sum rulesFeb 26 2010Jul 20 2010We evaluate the mass of the $B_{s0}$ scalar meson and the coupling constant in the $B_{s0} B K$ vertex in the framework of QCD sum rules. We consider the $B_{s0}$ as a tetraquark state to evaluate its mass. We get $m_{B_s0}=(6.04\pm 0.08) \GeV$, which ... More

Quantum Spectra of Triangular Billiards on the SphereNov 13 2000We study the quantal energy spectrum of triangular billiards on a spherical surface. Group theory yields analytical results for tiling billiards while the generic case is treated numerically. We find that the statistical properties of the spectra do not ... More

Linear hydrodynamics and viscoelasticity of nematic elastomersJan 04 2001We develop a continuum theory of linear viscoelastic response in oriented monodomain nematic elastomers. The expression for dissipation function is analogous to the Leslie-Ericksen version of anisotropic nematic viscosity; we propose the relations between ... More

The Hypercentral Constituent Quark Model and its symmetryJul 10 2015The hypercentral CQM, which is inspired by Lattice QCD calculations for quark-antiquark potentials, is presented, stressing its underlying symmetry. Its results for the spectrum, the helicity amplitudes and the elastic form factors are briefly reported. ... More

A systematic study of longitudinal and transverse helicity amplidutes in the hypercentral Constituent Quark ModelJun 03 2015We report in a systematic way the predictions of the non-relativistic hypercentral Constituent Quark model for the electromagnetic excitations of baryon resonances. The longitudinal and transverse helicity amplitudes are calculated with no free parameters ... More

On the proton radius problemNov 01 2013The recent values of the proton charge radius obtained by means of muonic-hydrogen laser spectroscopy are about $4\%$ different from the electron scattering data. It has been suggested that the proton radius is actually measured in different frames and ... More

Primordial magnetic fields, anomalous isocurvature fluctuations and Big Bang nucleosynthesisAug 11 1997We show that the presence of primordial stochastic (hypercharge) magnetic fields before the electroweak (EW) phase transition induces isocurvature fluctuations (baryon number inhomogeneities). Depending on the details of the magnetic field spectrum and ... More

High-Velocity Clouds Related to the Magellanic SystemSep 03 1999Mar 08 2001The results of the interaction between the Milky Way and the Magellanic Clouds are revealed through several high velocity complexes which are connected to the Clouds. The exact mechanism of their formation is under some debate, but they remain the only ... More

NLO QCD corrections to the production of off--shell WW pairs at $e^+ e^-$ collidersSep 13 1995Sep 20 1995QCD corrections to $e^+e^- \ra WW \ra q_1 \bar q_1 q_2 \bar q_2$ are computed and presented in a form which allows to impose realistic cuts on the structure of the observed events. QCD radiation substantially modifies the jet--jet invariant mass distributions ... More

Charged Particle-Image Interaction Near a Conducting SurfaceMay 20 2002May 22 2002The interaction of a bulk electron with conducting surfaces is studied by means of Bohm-Pines transformation in the second quantization formalism. The effective interaction potentials are obtained for the case of one plane and two plane configurations ... More

Time evolution for quantum systems at finite temperatureJul 03 1998This paper investigates a new formalism to describe real time evolution of quantum systems at finite temperature. A time correlation function among subsystems will be derived which allows for a probabilistic interpretation. Our derivation is non-perturbative ... More

Heterogeneity of link weight and the evolution of cooperationJul 24 2015Oct 31 2015In this paper, we investigate the effect of "heterogeneity of link weight", heterogeneity of the frequency or amount of interactions among individuals, on the evolution of cooperation. Based on an analysis of the evolutionary prisoner's dilemma game on ... More

Single W-boson Production at Linear CollidersSep 01 1999The process of single W-boson production at the energies of Next Linear Colliders is considered. We discuss in details the contributions from s and t channel diagrams, technical aspects of the complete tree level calculation with a finite W width, and ... More

Hot and cool plasma ejections in the solar coronaMar 04 2012We present the results of the first attempt of statistical research devoted to the association between X-ray Plasma Ejections (XPEs) and prominences. For this aim, we compared contents of a catalogue of XPEs, observed by the Soft X-ray Telescope onboard ... More

Comment on "Spin-Glass Solution of the Double-Exchange Model in Infinite Dimensions"Apr 16 2006In a paper submitted to the Arxive some time ago (cond-mat/0509270), R. S. Fishman et al. considered double-exchange model on a Bethe lattice in infinite dimensions using dynamical mean-field theory. We present a somewhat different derivation of their ... More

Luminous X-ray AGN in Clusters of GalaxiesMar 03 2010We present a study of X-ray AGN overdensities in 16 Abell clusters, within the redshift range 0.073<z<0.279, in order to investigate the effect of the hot inter-cluster environment on the triggering of the AGN phenomenon. The X-ray AGN overdensities, ... More

Reconstructing Positions and Peculiar Velocities of Galaxy Clusters within 20000 km/sec. I: The Cluster 3D DipoleJan 10 1995Jan 12 1995Starting from the observed distribution of galaxy clusters in redshift space we use a two--step procedure to recover their distances and peculiar velocities. After statistically correcting for the unobserved cluster distribution in the zone of avoidance ... More

The structure factor of fat deterministic Vicsek fractals: a small-angle scattering studyJul 16 2015We study here the small-angle scattering structure factor for deterministic fat fractals in the reciprocal space. It is shown that fat fractals are exact self-similar in the range of iterations having the same values of the scaling factor, and therefore ... More

Impact of intrinsic localized modes of atomic motion on materials propertiesJan 26 2010Sep 14 2010Recent neutron and x-ray scattering measurements show intrinsic localized modes (ILMs) in metallic uranium and ionic sodium iodide. Here, the role ILMs play in the behavior of these materials is examined. With the thermal activation of ILMs, thermal expansion ... More

Intrinsic Localized Lattice Modes and Thermal Transport: Potential Application in a Thermal RectifierMay 18 2009Recent experiments provide evidence of intrinsic localized modes (ILMs) in the lattice dynamics of conventional 3D materials. Here evidence that ILMs in uranium metal enhance the thermal conductivity is presented along with speculation on how thermal ... More

Flavor Asymmetry in Hyperons and Drell-Yan ProcessesJun 30 1998SU(3), baryon octets and a meson cloud model are compared for the flavor asymmetry of sea quarks in the $\Sigma^+$, as an example. Large differences are found, especially between SU(3) and the meson cloud model. We suggest Drell-Yan measurements of $\Sigma^{+}-p$ ... More

Universality in Efimov associated tetramers in 4HeSep 08 2014Nov 02 2014We calculated, using seven realistic 4He-4He potentials in the literature, the Efimov spectra of the 4He trimer and tetramer and analyzed the universality of the systems. The three-(four-)body Schroedinger equations were solved fully nonadiabatically ... More

XMM-Newton discovery of soft X-ray absorption in the high-z superluminous Blazar RBS 315Sep 16 2005We present the analysis and the results of a 20 ks XMM-Newton observation of the extremely X-ray loud (L_X ~ 5 x 10^{47} erg/s) flat-spectrum radio quasar RBS 315 at a redshift of 2.69. This EPIC observation has allowed us to strongly constrain the slope ... More

Calculating the Potato Radius of Asteroids using the Height of Mt. EverestNov 07 2015At approximate radii of 200-300 km, asteroids transition from oblong `potato' shapes to spheres. This limit is known as the Potato Radius, and has been proposed as a classification for separating asteroids from dwarf planets. The Potato Radius can be ... More

Replica symmetry breaking for anisotropic magnets with quenched disorderMar 21 2016Jun 15 2016We study critical behaviour of disordered magnets: the system with cubic anisotropy and scalar disorder and that with random direction of anisotropy axis. The quenched disorder is taken into account by replica method. We derive to first order in $\epsilon$ ... More

Non-Linear Trans-Planckian Corrections of Spectra due to the Non-trivial Initial StatesOct 06 2014Recent Planck results motivated us to use non-Bunch-Davies vacuum. In this paper, we use the excited-de Sitter mode as non-linear initial states during inflation to calculate the corrected spectra of the initial fluctuations of the scalar field. First, ... More

Universal hydrodynamics and charged hadron multiplicity at the LHCAug 19 2011Time evolution of a "little bang" created in heavy ion collisions can be divided into two phases, the pre-equilibrium and hydrodynamic. At what moment the evolution becomes hydrodynamic and is there any universality in the hydrodynamic flow? To answer ... More

Geometrization of Econophysics : An Alternative Approach for Measuring Elements of Risk Management of an Economic SystemOct 08 2013Oct 16 2013The relationship between micro-structure and macro-structure of complex systems using information geometry has been dealt by several authors. From this perspective, we are going to apply it as a geometrical structure connecting both microeconomics and ... More

Three-dimensional electromagnetic modeling of practical superconductors for power applicationsMay 31 2016HTS are feasible for hight power applications because of the smaller consumption demand of the cooling system in comparison to the whole power device. Real industral devices contain superconductors with 2D and 3D geometry (coated conductors tapes represent ... More

Real-space perturbation theory for frustrated magnets: application to magnetization plateausDec 23 2014We present a unified approach to the problem of degeneracy lifting in geometrically frustrated magnets with and without an external field. The method treats fluctuations around a classical spin configuration in terms of a real-space perturbation expansion. ... More

Octupolar ordering of classical kagome antiferromagnets in two and three dimensionsMay 06 2008Sep 16 2008Classical Heisenberg antiferromagnets on two-dimensional kagome and three-dimensional hyperkagome lattices are investigated by Monte Carlo simulations. For both models the symmetry-breaking states at low temperatures are described by non-zero octupole ... More

The Hurwitz Equivalence Problem is UndecidableNov 07 2005Nov 07 2005In this paper, we prove that the Hurwitz equivalence problem for 1-factorizations in $F_2 \oplus F_2$ is undecidable, and as a consequence, the Hurwitz equivalence problem for $\Delta^2$-factorizations in the braid groups $B_n, n\geq 5$ is also undecidable. ... More

An improved bound on distillable entanglementSep 28 1998Oct 30 2000The best bound known on 2-locally distillable entanglement is that of Vedral and Plenio, involving a certain measure of entanglement based on relative entropy. It turns out that a related argument can be used to give an even stronger bound; we give this ... More

Neutrino Emission from Superfluid Neutron-Star Cores: Various Types of Neutron PairingApr 19 2002We calculate and provide analytic fits of the factors which describe the reduction of the neutrino emissivity of modified Urca and nucleon-nucleon bremsstrahlung processes by superfluidity of neutrons and protons in neutron-star cores. We consider $^1$S$_0$ ... More

Bulk viscosity of superfluid neutron starsApr 09 2007Oct 02 2007The hydrodynamics, describing dynamical effects in superfluid neutron stars, essentially differs from the standard one-fluid hydrodynamics. In particular, we have four bulk viscosity coefficients in the theory instead of one. In this paper we calculate ... More

Convergence of the self-energy in a relativistic chiral quark model: excited Nucleon and $Δ$ sectorFeb 12 2010Feb 26 2010A convergence of the valence quark self-energies in the 1S, 2S, $1P_{1/2}$, $1P_{3/2}$ orbits induced by pion and gluon field configurations, is shown in the frame of a relativistic chiral quark model. It is shown that in order to reach a convergence, ... More

A periodic table for the excited Nucleon and Delta spectrum in a relativistic chiral quark modelMar 18 2011Oct 28 2011A possibility of the construction of a periodic table for the excited baryon spectrum is shown in the frame of a relativistic chiral quark model based on selection rules derived from the one-pion exchange mechanism. It is shown that all the $N^*$ and ... More

Dynamical self-organization acting as physical basis of the ball lightning phenomenonJun 04 2010Oct 14 2010Lightning balls are very rare natural phenomena that appear as free floating glowing globs, usually during electric activity in the atmosphere of the Earth. Each year, hundreds of eyewitness accounts of such strange events are reported to local journals, ... More

Community detection in networks: Modularity optimization and maximum likelihood are equivalentJun 07 2016We demonstrate an exact equivalence between two widely used methods of community detection in networks, the method of modularity maximization in its generalized form which incorporates a resolution parameter controlling the size of the communities discovered, ... More

Prediction of highly cited papersOct 30 2013In an article written five years ago [arXiv:0809.0522], we described a method for predicting which scientific papers will be highly cited in the future, even if they are currently not highly cited. Applying the method to real citation data we made predictions ... More

Spectral methods for network community detection and graph partitioningJul 29 2013We consider three distinct and well studied problems concerning network structure: community detection by modularity maximization, community detection by statistical inference, and normalized-cut graph partitioning. Each of these problems can be tackled ... More

Component sizes in networks with arbitrary degree distributionsJun 30 2007We give an exact solution for the complete distribution of component sizes in random networks with arbitrary degree distributions. The solution tells us the probability that a randomly chosen node belongs to a component of size s, for any s. We apply ... More

Modularity and community structure in networksFeb 17 2006Many networks of interest in the sciences, including a variety of social and biological networks, are found to divide naturally into communities or modules. The problem of detecting and characterizing this community structure has attracted considerable ... More

Mixing patterns in networksSep 19 2002Feb 04 2003We study assortative mixing in networks, the tendency for vertices in networks to be connected to other vertices that are like (or unlike) them in some way. We consider mixing according to discrete characteristics such as language or race in social networks ... More

Community detection and graph partitioningMay 21 2013Many methods have been proposed for community detection in networks. Some of the most promising are methods based on statistical inference, which rest on solid mathematical foundations and return excellent results in practice. In this paper we show that ... More

Random graphs with clusteringMar 24 2009We offer a solution to a long-standing problem in the physics of networks, the creation of a plausible, solvable model of a network that displays clustering or transitivity -- the propensity for two neighbors of a network node also to be neighbors of ... More

Finding community structure in networks using the eigenvectors of matricesMay 10 2006Jul 23 2006We consider the problem of detecting communities or modules in networks, groups of vertices with a higher-than-average density of edges connecting them. Previous work indicates that a robust approach to this problem is the maximization of the benefit ... More

The structure of scientific collaboration networksJul 12 2000We investigate the structure of scientific collaboration networks. We consider two scientists to be connected if they have authored a paper together, and construct explicit networks of such connections using data drawn from a number of databases, including ... More

Formal loops III: Factorizing functions and the Radon transformOct 21 2005Oct 25 2005To any algebraic variety X and and closed 2-form \omega on X, we associate the "symplectic action functional" T(\omega) which is a function on the formal loop space LX introduced by the authors in math.AG/0107143. The correspondence \omega --> T(\omega) ... More

Existence of weak solutions for unsteady motions of micro-polar electrorheological fluidsOct 01 2015In this paper we study the existence of weak solutions to an unsteady system describing the motion of micro-polar electrorheological fluids. The constitutive relations for the stress tensors belong to the class of generalized Newtonian fluids. Using the ... More

Higher Order and Harmonic Corrections to the Quasi-de Sitter InflationJun 13 2016Jun 14 2016Since the trans-Planckian considerations can be associated with the re-definition of the initial vacuum, we investigate further the influence of trans-planckian physics on the spectra produced by initial quasi-de Sitter (dS) state during inflation. Recently, ... More

Deformation types of real and complex manifoldsNov 22 2001Jan 30 2002The Leit-Faden of the article (which is partially a survey) is a negative answer to the question whether, for a compact complex manifold which is a $K(\pi, 1)$ the diffeomorphism type determines the deformation type. We show that a deformation in the ... More

Does a magnetic field modify the critical behaviour at the metal-insulator transition in 3-dimensional disordered systems?Aug 12 1994The critical behaviour of 3-dimensional disordered systems with magnetic field is investigated by analyzing the spectral fluctuations of the energy spectrum. We show that in the thermodynamic limit we have two different regimes, one for the metallic side ... More

Quasi-plane waves for a particle with spin 1/2 on the background of Lobachevsky geometry: simulating of a special mediumMar 19 2012In the paper complete systems of exact solutions for Dirac and Weyl equations in the Lobachevsky space are constructed on the base of the method of separation of the variables in quasi-cartesian coordinates. An extended helicity operator is introduced. ... More

Quantum Kepler problem for spin 1/2 particle in spaces on constant curvature. I. Pauli theorySep 28 2011Transition to a nonrelativistic Pauli equation in Riemann space of constant positive curvature for a Dirac particle in presence of the Coulomb field is performed in the system of radial equations, exact solutions are constructed in terms of Hein functions, ... More

The Calogero Model and the Virasoro SymmetryNov 14 1994We construct new realizations of the Virasoro algebra inspired by the Calogero model. The Virasoro algebra we find acts as a kind of spectrum-generating algebra of the Calogero model. We furthermore present the superextension of these results and introduce ... More

What is the origin of the mass of the Higgs boson?Sep 21 2012The purpose of this paper is to present a unified description of mass generation mechanisms that have been investigated so far and that are called the Mach and Higgs proposals. In our mechanism, gravity acts merely as a catalyst and the final expression ... More

On properties of the space of quantum states and their application to construction of entanglement monotonesApr 09 2008Dec 22 2011We consider two properties of the set of quantum states as a convex topological space and some their implications concerning the notions of a convex hull and of a convex roof of a function defined on a subset of quantum states. By using these results ... More

The Convex Closure of the Output Entropy of Infinite Dimensional Channels and the Additivity ProblemAug 10 2006The continuity properties of the convex closure of the output entropy of infinite dimensional channels and their applications to the additivity problem are considered. The main result of this paper is the statement that the superadditivity of the convex ... More

Properties of probability measures on the set of quantum states and their applicationsJul 11 2006Mar 27 2011Two basic properties of the set of all probability measures on the set of quantum states and their corollaries are considered. Several applications of these properties to analysis of functional constructions widely used in quantum information theory are ... More

On channels with finite Holevo capacityFeb 07 2006We consider a nontrivial class of infinite dimensional quantum channels characterized by finiteness of the Holevo capacity. Some general properties of channels of this class are described. In particular, a special sufficient condition of existence of ... More

On the additivity conjecture for channels with arbitrary constraintsAug 29 2003Recently Shor proved equivalence of several open (sub)additivity problems related to the Holevo capacity and the entanglement of formation [15]. In our previous note [6] equivalence of these to the additivity of the Holevo capacity for channels with arbitrary ... More

The Schmidt number and partially entanglement breaking channels in infinite dimensionsOct 19 2011Dec 15 2011A definition of the Schmidt number of a state of an infinite dimensional bipartite quantum system is given and properties of the corresponding family of Schmidt classes are considered. The existence of states with a given Schmidt number such that any ... More

On the structure of optimal sets for tensor product channelFeb 24 2004Jun 28 2005For a given quantum channel we consider two optimal sets of states, related to the Holevo capacity and to the minimal output entropy of this channel. Some properties of these sets as well as the necessary and sufficient condition for their coincidence ... More