Results for "Irina Stockem"

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Anomalous phonon lifetime shortening in paramagnetic CrN caused by magneto-lattice coupling: A combined spin and ab initio molecular dynamics studyFeb 08 2018We study the mutual coupling of spin fluctuations and lattice vibrations in paramagnetic CrN by combining atomistic spin dynamics and ab initio molecular dynamics. The two degrees of freedom are dynamically coupled leading to non-adiabatic effects. Those ... More
PIC simulations of the Thermal Anisotropy-Driven Weibel Instability: Field growth and phase space evolution upon saturationMay 14 2009The Weibel instability is investigated with PIC simulations of an initially unmagnetized and spatially uniform electron plasma. This instability, which is driven by the thermally anisotropic electron distribution, generates electromagnetic waves with ... More
Constraints for the aperiodic O-mode streaming instabilityNov 06 2014Dec 21 2014In plasmas where the thermal energy density exceeds the magnetic energy density ($\beta_\parallel > 1$), the aperiodic ordinary mode (O-mode) instability is driven by an excess of parallel temperature $A = T_\perp /T_\parallel < 1$ (where $\parallel$ ... More
General Results on Conditional Symmetry for the Two-Dimensional Nonlinear Wave EquationOct 12 2009We present full classification of Q-conditional symmetries for the two-dimensional nonlinear wave equation.
Elementary Superconductivity in Nonlinear Electrodynamics Coupled to GravityOct 05 2015Source-free equations of nonlinear electrodynamics minimally coupled to gravity admit regular axially symmetric asymptotically Kerr-Newman solutions which describe charged rotating black holes and electromagnetic spinning solitons (lumps). Asymptotic ... More
Electromagnetic source for the Kerr-Newman geometryOct 02 2015Source-free equations of nonlinear electrodynamics minimally coupled to gravity (NED-GR) admit regular axially symmetric asymptotically Kerr-Newman solutions, which describe electrically charged rotating black holes and spinning solitons. Asymptotic analysis ... More
The subword complexity of a class of infinite binary wordsDec 13 2005Let $A_q$ be a $q$-letter alphabet and $w$ be a right infinite word on this alphabet. A subword of $w$ is a block of consecutive letters of $w$. The subword complexity function of $w$ assigns to each positive integer $n$ the number $f_w(n)$ of distinct ... More
Variable cosmological term - geometry and physicsOct 04 2000We describe the dynamics of a cosmological term in the spherically symmetric case by an r-dependent second rank symmetric tensor \Lambda_{\mu\nu} invariant under boosts in the radial direction. The cosmological tensor \Lambda_{\mu\nu} represents the extension ... More
Studies of charmless B decays including CP violation effectsAug 03 2013Aug 08 2013The latest experimental results in charmless B decays are presented with a focus on CP violation measurements. These include the first observation of CP violation in B_s decays, evidence for CP violation in charmless three-body B+ decays, branching fraction ... More
Cosmological term as a source of massDec 20 2001In the spherically symmetric case the dominant energy condition together with the requirements of regularity at the center, asymptotic flatness and fineteness of the ADM mass, defines the family of asymptotically flat globally regular solutions to the ... More
Towards a heat kernel expansion for the electromagnetic field interacting with a dielectric body of arbitrary formDec 16 2003The results on the heat kernel expansion for the electromagnetic field in the background of dielectric media are briefly reviewed. The common approaches to the calculation of the heat kernel coefficients are discussed from the viewpoint of their applicability ... More
Differential Invariants and Construction of Conditionally Invariant EquationsApr 19 2003New concept of conditional differential invariant is discussed that would allow description of equations invariant with respect to an operator under a certain condition. Example of conditional invariants of the projective operator is presented.
Differential Invariants and Hidden SymmetryOct 26 2010Feb 28 2011We describe some classes of PDE that display hidden symmetry, with reduced equations having additional symmetry operators compared to the initial equations. Relations between the concepts of hidden and conditional symmetry, and between hidden symmetry ... More
Support of Non-separable Multivariate Scaling FunctionDec 31 2007We make an estimation of the support of a multivariable scaling function for an arbitrary dilation matrix. We give a method of calculating the values of the scaling function on a tight set using the knowledge of the size of the support.
Delta Waves for a Strongly Singular Initial-Boundary Hyperbolic Problem with Integral Boundary ConditionJan 31 2004We investigate the existence and the singular structure of delta wave solutions to a semilinear strictly hyperbolic equation with strongly singular initial and boundary conditions. The boundary conditions are given in nonlocal form with a linear integral ... More
Fredholm Solvability of Periodic Neumann Problem for a Linear Telegraph EquationJun 08 2011We investigate the linear telegraph equation $$ u_{tt}-u_{xx}+2\mu u_t=f(x,t) $$ with periodic Neumann boundary conditions. We prove that the operator of the problem is modeled as a Fredholm operator of index zero in the scale of Sobolev-type spaces of ... More
Initial-Boundary Problems for Semilinear Hyperbolic Systems with Singular CoefficientsSep 14 2004We use the framework of Colombeau algebras of generalized functions to study existence and uniqueness of global generalized solutions to mixed non-local problems for a semilinear hyperbolic system. Coefficients of the system as well as initial and boundary ... More
A Distributional Solution to a Hyperbolic Problem Arising in Population DynamicsJan 31 2004Feb 04 2007We consider a generalization of the Lotka-McKendrick problem describing the dynamics of an age-structured population with time-dependent vital rates. The generalization consists in allowing the initial and the boundary conditions to be derivatives of ... More
$C^1$-smoothness of Nemytskii operators on Sobolev-type spaces of periodic functionsJul 22 2011Dec 02 2011We consider a class of Nemytskii superposition operators that covers the nonlinear part of traveling wave models from laser dynamics, population dynamics, and chemical kinetics. Our main result is the $C^1$-continuity property of these operators over ... More
Local Energy Statistics in Directed PolymersFeb 06 2007Recently, Bauke and Mertens conjectured that the local statistics of energies in random spin systems with discrete spin space should, in most circumstances, be the same as in the random energy model. We show that this conjecture holds true as well for ... More
On the absolute constants in the Berry-Esseen type inequalities for identically distributed summandsNov 28 2011By a modification of the method that was applied in (Korolev and Shevtsova, 2010), here the inequalities $\Delta_n\leq0.3328(\beta_3+0.429)/\sqrt{n}$ and $\Delta_n\leq0.33554(\beta_3+0.415)/\sqrt{n}$ are proved for the uniform distance $\Delta_n$ between ... More
Finite basis problem for identities with involutionOct 08 2014Dec 06 2014We consider associative algebras with involution over a field of characteristic zero. We proved that any algebra with involution satisfies the same identities with involution as the Grassmann envelope of some finite dimensional $Z_4$-graded algebra with ... More
How accurate is the local-duality model for the pion elastic form factor?Sep 21 2010We study the accuracy of the pion form factor, obtained with a local-duality version of dispersive sum rules. To probe this accuracy, we make use of a potential model, where the exact form factor may be calculated from the solution of the Schroedinger ... More
Maximal subalgebras of the classical linear Lie superalgebrasNov 17 2013Dynkin's classification of maximal subalgebras of simple finite dimensional complex Lie algebras is generalized to linear Lie superalgebras. Namely, the maximal non-simple irreducible subalgebras of $\mathfrak{gl}(p|q), \mathfrak{q}(n), \mathfrak{sl}(p|q), ... More
Triple-horizon spherically symmetric spacetime and holographic principleJun 11 2012We present a family of spherically symmetric spacetimes, specified by the density profile of a vacuum dark energy, which have the same global structure as the de Sitter spacetime but the reduced symmetry which leads to a time-evolving and spatially inhomogeneous ... More
Regular electrically charged structures in Nonlinear Electrodynamics coupled to General RelativityJul 19 2004Aug 19 2004We address the question of existence of regular spherically symmetric electrically charged solutions in Nonlinear Electrodynamics coupled to General Relativity. Stress-energy tensor of the electromagnetic field has the algebraic structure $T_0^0=T_1^1$. ... More
$Λ^{mu}_ν$ geometries from the point of view of different observersOct 06 2003$\Lambda^{\mu}_{\nu}$-geometry is a geometry with a variable cosmological term described by a second-rank symmetric tensor $\Lambda^{\mu}_{\nu}$ whose asymptotics are Einstein cosmological term $\Lambda \delta ^{\mu}_{\nu}$ at the origin and $\lambda ... More
Cosmological term, mass, and space-time symmetryOct 06 2003Dec 19 2003In the spherically symmetric case the requirements of regularity of density and pressures and finiteness of the ADM mass $m$, together with the weak energy condition, define the family of asymptotically flat globally regular solutions to the Einstein ... More
On evaluation of the topological degree of the Poincare map in some singular situationsNov 05 2010In the paper we develop a method to evaluate the topological degree of the Poincare map of the mathematical model of narrow lagoon subject to a T-periodic forcing. Using the method developved we arrive to the conditions for the parameteres that guarantee ... More
Energy Distribution of a Schwarzschild Black Hole in a Magnetic UniverseOct 25 2000We obtain the energy distribution of a Schwarzschild black hole in a magnetic universe in the Tolman prescription.
One metric result about analytic continuation of some Dirichlet seriesDec 10 2007In this paper we consider certain 1-parametric family of Dirichlet series. For a particular value of the parameter the series turns into the Dirichlet series for the Riemann zeta function. We prove that almost every series of the family has analytic continuation ... More
Some measure-theoretic properties of U-statistics applied in statistical physicsJul 14 2015This paper investigates the relationship between various measure-theoretic properties of U-statistics with fixed sample size $N$ and the same properties of their kernels. Specifically, the random variables are replaced with elements in some measure space ... More
Generalized Solutions to Hyperbolic Systems with Nonlinear Conditions and Strongly Singular DataApr 05 2005Using the framework of Colombeau algebras of generalized functions, we prove the existence and uniqueness results for global generalized solvability of semilinear hyperbolic systems with nonlinear nonlocal boundary conditions. We admit strong singularities ... More
Smoothing effect and Fredholm property for first-order hyperbolic PDEsFeb 28 2012Jun 25 2012We give an exposition of recent results on regularity and Fredholm properties for first-order one-dimensional hyperbolic PDEs. We show that large classes of boundary operators cause an effect that smoothness increases with time. This property is the key ... More
A note on Poisson brackets for orthogonal polynomials on the unit circleJan 02 2007Oct 24 2011The connection of orthogonal polynomials on the unit circle (OPUC) to the defocusing Ablowitz-Ladik integrable system involves the definition of a Poisson structure on the space of Verblunsky coefficients. In this paper, we compute the complete set of ... More
A note on circular trace formulaeJun 22 2006We find a finite CMV matrix whose eigenvalues coincide with the Dirichlet data of a circular periodic problem. As a consequence, we obtain circular analogues of the classical trace formulae for periodic Jacobi matrices.
CMV matrices in random matrix theory and integrable systems: a surveyOct 12 2005We present a survey of recent results concerning a remarkable class of unitary matrices, the CMV matrices. We are particularly interested in the role they play in the theory of random matrices and integrable systems. Throughout the paper we also emphasize ... More
A characterization of the inclusions between mixed norm spacesOct 17 2014Jun 24 2015We consider the mixed norm spaces of Hardy type studied by Flett and others. We study some properties of these spaces related to mean and pointwise growth and complement some partial results by various authors by giving a complete characterization of ... More
Lax pairs for the Ablowitz-Ladik system via orthogonal polynomials on the unit circleDec 14 2004Nenciu and Simon found that the analogue of the Toda system in the context of orthogonal polynomials on the unit circle is the defocusing Ablowitz-Ladik system. In this paper we use the CMV and extended CMV matrices, respectively, to construct Lax pair ... More
Uniform Asymptotic Solutions of a System of two Schrödinger Equations with Potential-Curve-Crossing PointApr 26 1994A formal uniform asymptotic solution of the system of differential equations $ h^{2}\frac{d^{2}U_{1}}{dz^{2}}+\Phi_{1} U_{1}=\alpha U_{2} $ , $ h^{2}\frac{d^{2}U_{2}}{dz^{2}}+\Phi_{2} U_{2}=\alpha U_{1}$ , for $ z\in D$ and for h real, large is obtained, ... More
The algebraic structure of a cosmological term in spherically symmetric solutionsDec 29 1999We propose to describe the dynamics of a cosmological term in the spherically symmetric case by an r-dependent second rank symmetric tensor invariant under boosts in the radial direction. This proposal is based on the Petrov classification scheme and ... More
Reduction of multidimensional non-linear d'Alembert equations to two-dimensional equations: ansatzes, compatibility of reduction conditionsNov 01 2006We study conditions of reduction of multidimensional wave equations - a system of d'Alembert and Hamilton equations. Necessary conditions for compatibility of such reduction conditions are proved. Possible types of the reduced equations and ansatzes are ... More
Isotropy index for the connected sum and the direct product of manifoldsAug 24 2016A subspace or subgroup is isotropic under a bilinear map if the restriction of the map on it is trivial. We study maximal isotropic subspaces or subgroups under skew-symmetric maps, and in particular the isotropy index---the maximum dimension of an isotropic ... More
The spectrum of the Laplace operator on connected compact simple rank four Lie groups. IJan 11 2016Feb 03 2016In this paper are given explicit calculations of Laplace operator spectrum for smooth real/complex-valued functions on all connected compact simple rank four Lie groups with biinvariant Riemannian metric, corresponding to root systems $B_4$, $C_4$, $D_4$ ... More
Immune Evasion through Competitive Inhibition: the Shielding Effect of non-Stem Cancer CellsAug 04 2014It has been recently proposed that the two "emerging" hallmarks of cancer, namely altered glucose metabolism and immune evasion, may in fact be fundamentally linked (Kareva and Hahnfeldt, 2013). This connection comes from up-regulation of glycolysis by ... More
Competition driven cancer immunoeditingJul 29 2014It is a well-established fact that tumors up-regulate glucose consumption to meet increasing demands for rapidly available energy by switching to purely glycolytic mode of glucose metabolism. What is often neglected is that cytotoxic cells of the immune ... More
Smoothing Solutions to Initial-Boundary Problems for First-Order Hyperbolic SystemsAug 15 2009Jun 08 2011We consider initial-boundary problems for general linear first-order strictly hyperbolic systems with local or nonlocal nonlinear boundary conditions. While boundary data are supposed to be smooth, initial conditions can contain distributions of any order ... More
Hyperbolic Problems in the Whole Scale of Sobolev-Type Spaces of Periodic FunctionsFeb 04 2007Jun 11 2007We study one-dimensional linear hyperbolic systems with $L^{\infty}$-coefficients subjected to periodic conditions in time and reflection boundary conditions in space. We derive a priori estimates and give an operator representation of solutions in the ... More
Classical solvability of nonlinear initial-boundary problems for first-order hyperbolic systemsJan 02 2008We prove the global classical solvability of initial-boundary problems for semilinear first-order hyperbolic systems subjected to local and nonlocal nonlinear boundary conditions. We also establish lower bounds for the order of nonlinearity demarkating ... More
An Inversion Formula for the Gaussian Radon Transform for Banach SpacesAug 06 2013We provide a disintegration theorem for the Gaussian Radon transform Gf on Banach spaces and use the Segal-Bargmann transform on abstract Wiener spaces to find a procedure to obtain f from its Gaussian Radon transform Gf.
Identities of finitely generated graded algebras with involutionOct 08 2014Dec 06 2014We consider associative algebras with involution graded by a finite abelian group G over a field of characteristic zero. Suppose that the involution is compatible with the grading. We represent conditions permitting PI-representability of such algebras. ... More
Ansatzes and exact solutions for nonlinear Schrodinger equationsDec 05 2014We consider construction of ansatzes for nonlinear Schrodinger equations in three space dimensions and arbitrary nonlinearity, and conditions of their reduction to ordinary differential equations. Complete description of ansatzes of certain types is presented. ... More
One proof of the original Kemer's theorems (concerning the text of C. Procesi "What happened to PI-theory", arxiv.org/abs/1403.5673)Mar 12 2015We consider associative algebras over a field of characteristic zero. We give a version of the proof of the Kemer's theorems concerning the Specht problem solution. It is proved that the ideal of graded identities of a finitely generated PI-superalgebra ... More
The Classical Inverse Problem for Multi-Particle Densities in the Canonical Ensemble FormulationJun 28 2014Jan 04 2015We provide sufficient conditions for the solution of the classical inverse problem in the canonical distribution for multi-particle densities. Specifically, we show that there exists a unique potential in the form of a sum of m-particle (m greater then ... More
Comment to "General Solution to Unidimensional Hamilton-Jacobi Equation" [arXiv:1302.0591v1]Apr 12 2013We present previous results on the general solution of the multidimensional Hamilton-Jacobi equation $\frac{\partial u}{\partial t} - \frac{\partial u}{\partial x_a} \frac{\partial u}{\partial x_a}= 0$ and methods that were used to find such general solution. ... More
Automated Marble Plate Classification System Based On Different Neural Network Input Training Sets and PLC ImplementationAug 16 2012The process of sorting marble plates according to their surface texture is an important task in the automated marble plate production. Nowadays some inspection systems in marble industry that automate the classification tasks are too expensive and are ... More
Reduction of non-linear d'Alembert equations to two-dimensional equationsOct 14 2009We study conditions of reduction of the multidimensional wave equation - a system of the d'Alembert and Hamilton equations. We prove necessary conditions for compatibility of such system of the reduction conditions. Possible types of the reduced equations ... More
The five exceptional simple Lie superalgebras of vector fieldsFeb 16 1997The five simple exceptional complex Lie superalgbras of vector fields are described. One of them is new; the other four are explicitely described for the first time. All of the exceptional Lie superalgebras are obtained with the help of the Cartan prolongation ... More
On the critical line zeros of $L$ -- functions attached to automorphic cusp formsDec 12 2012We prove for L-function attached to an automorphic cusp form for the Hecke congruence group $\Gamma_0(D)$, which is also an eigenfunction of all the Hecke operators, that a positive proportion of its non-trivial zeros lie on the critical line. This result ... More
Differential Invariants of Infinite-Dimensional Algebras That Are Equivalence Algebras of Classes of PDEOct 12 2009We describe differential invariants of infinite-dimensional algebras being equivalence algebras of some classes of PDE and study structure of these algebras.
From vacuum nonsingular black hole to variable cosmological constantJan 17 2002We outline the class of globally regular spherically symmetric solutions to the minimally coupled GR equations asymptotically de Sitter in the origin and asymptotically Schwarzschild at infinity. A source term connects smoothly de Sitter vacuum at the ... More
Energy Distribution of a Charged Regular Black HoleNov 20 2000We calculate the energy distribution of a charged regular black hole by using the energy-momentum complexes of Einstein and M{\o}ller.
Energy of a Conformal Scalar Dyon Black HoleOct 25 2000We obtain the energy of a conformal scalar dyon black hole (CSD) by using the energy-momentum complexes of Tolman and M{\o}ller. The total gravitational energy is given by the CSD charge in the both prescriptions.
On the Fredholm Solvability for a Class of Multidimensional Hyperbolic ProblemsFeb 20 2008Jan 10 2011We prove the Fredholm alternative for a class of two-dimensional first-order hyperbolic systems with periodic-Dirichlet boundary conditions. Our approach is based on a regularization via a right parametrix.
On the accuracy of the approximation of the complex exponent by the first terms of its Taylor expansion with applicationsJan 13 2013Dec 13 2013A new bound for the remainder term in the Taylor expansion of the complex exponent $e^{ix}$, $x\in\R$, is proved yielding precise moment-type estimates of the accuracy of the approximation of the characteristic function (the Fourier--Stieltjes transform) ... More
A square bias transformation: properties and applicationsDec 30 2012Dec 13 2013The properties of the square bias transformation are studied, in particular, the precise moment-type estimate for the $L_1$-metric between the transformed and the original distributions is proved, a relation between their characteristic functions is found. ... More
The co-rank of the fundamental group: the direct product, the first Betti number, and the topology of foliationsJun 20 2015We study $b'_1(M)$, the co-rank of the fundamental group of a smooth closed connected manifold $M$. We calculate this value for the direct product of manifolds. We characterize the set of all possible combinations of $b'_1(M)$ and the first Betti number ... More
Moduli Spaces of Planar Pentagonal Linkages: Combinatorial DescriptionMay 29 2013May 30 2013Moduli spaces of planar polygonal linkages admit a cell structure which can be realized as a surgery on the permutohedron. We present a 3D visualization of the result of the surgery for all types of non-degenerate pentagonal linkages.
On the Structure of the Bochner-Martinelli Residue CurrentsMar 22 2016We study residue currents of the Bochner--Martinelli type using their relationship with Mellin transforms of residue integrals. We present the structure formula for residue currents associated with monomial mappings: they admit representations as sums ... More
Finitely generated algebras with involution and their identitiesJun 26 2012Feb 11 2013Associative algebras with involution over a field of zero characteristic are considered. It is proved that in this case for any finitely generated associative algebra with involution there exists a finite dimensional algebra with involution which satisfies ... More
Spinning superconducting electrovacuum solitonJul 24 2006In nonlinear electrodynamics coupled to general relativity and satisfying the weak energy condition, a spherically symmetric electrically charged electrovacuum soliton has obligatory de Sitter center in which the electric field vanishes while the energy ... More
Spherically symmetric space-time with the regular de Sitter centerApr 30 2003The requirements are formulated which lead to the existence of the class of globally regular solutions to the minimally coupled GR equations which are asymptotically de Sitter at the center. The brief review of the resulting geometry is presented. The ... More
Intelligent Technologies in Model Base Management System Design AutomationApr 24 2010The article describes the prospects of model base management system design automation for decision support systems and suggests the toolbox scheme for design automation based on intelligent technologies.
Maximal subalgebras of matrix Lie superalgebrasFeb 16 1997Dynkin's classification of maximal subalgebras of simple finite dimensional complex Lie algebras is generalized to Lie subsuperalgebras of the general linear Lie superalgebras.
How to realize Lie algebras by vector fieldsSep 21 2005An algorithm for embedding finite dimensional Lie algebras into Lie algebras of vector fields (and Lie superalgebras into Lie superalgebras of vector fields) is offered in a way applicable over ground fields of any characteristic. The algorithm is illustrated ... More
Differential Invariants for Infinite-Dimensional AlgebrasJul 02 2006We present an approach for construction of functional bases of differential invariants for some infinite-dimensional algebras with coefficients of generating operators depending on arbitrary functions. An example for the infinite-dimensional Poincare-type ... More
On Regularity of the Product of DistributionsApr 02 2004Aug 03 2004This paper has been withdrawn by the author due to a gap in the proof of the main result.
Co-rank and Betti number of a groupFeb 08 2015We study the maximal ranks of a free and a free abelian quotients of a finitely generated group, called co-rank (inner rank, cut number) and the Betti number, respectively. We show that any combination of these values within obvious constraints is realized ... More
Collisionless Weibel shocks: full formation mechanism and timingJun 16 2014Collisionless shocks in plasmas play an important role in space physics (Earth's bow shock) and astrophysics (supernova remnants, relativistic jets, gamma-ray bursts, high energy cosmic rays). While the formation of a fluid shock through the steepening ... More
Physics of collisionless shocks - theory and simulationSep 16 2015Collisionless shocks occur in various fields of physics. In the context of space and astrophysics they have been investigated for many decades. However, a thorough understanding of shock formation and particle acceleration is still missing. Collisionless ... More
Shock formation in electron-ion plasmas: mechanism and timingApr 02 2015We analyse the full shock formation process in electron-ion plasmas in theory and simulations. It is accepted that electromagnetic shocks in initially unmagnetised relativistic plasmas are triggered by the filamentation instability. However, the transition ... More
Spectro-Polarimetric Properties of Small-Scale Plasma Eruptions Driven by Magnetic Vortex TubesJul 08 2014Highly turbulent nature of convection on the Sun causes strong multi-scale interaction of subsurface layers with the photosphere and chromosphere. According to realistic 3D radiative MHD numerical simulations ubiquitous small-scale vortex tubes are generated ... More
Some Aspects of the Electromagnetic Multipole ExpansionsMar 19 2005Various procedures for expressing the multipolar expansion of the electromagnetic field are considered with application to the calculation of the radiated power. Some results from literature are discussed and perspective of developing the subject is pointed ... More
Regular rotating electrically charged black holes and solitons in nonlinear electrodynamics minimally coupled to gravityOct 02 2015In nonlinear electrodynamics coupled to gravity, regular spherically symmetric electrically charged solutions satisfy the weak energy condition and have obligatory de Sitter centre. By the G\"urses-G\"ursey algorithm they are transformed to spinning electrically ... More
Appendix for almost-rainbow edge-colorings of some small subgraphsDec 19 2011Sep 20 2012This appendix for our article, "Almost-rainbow edge-colorings of some small subgraphs", contains the full proof of Theorem 4.1.
On a game on graphsFeb 22 2013We start with the well-known game below: Two players hold a sheet of paper to their forehead on which a positive integer is written. The numbers are consecutive and each player can only see the number of the other one. In each time step, they either say ... More
Distributional Models and Deep Learning Embeddings: Combining the Best of Both WorldsDec 19 2013Feb 18 2014There are two main approaches to the distributed representation of words: low-dimensional deep learning embeddings and high-dimensional distributional models, in which each dimension corresponds to a context word. In this paper, we combine these two approaches ... More
Meixner class of orthogonal polynomials of a non-commutative monotone Levy noiseSep 29 2016Let $(X_t)_{t\ge0}$ denote a non-commutative monotone L\'evy process. Let $\omega=(\omega(t))_{t\ge0}$ denote the corresponding monotone L\'evy noise.. A continuous polynomial of $\omega$ is an element of the corresponding non-commutative $L^2$-space ... More
Almost-rainbow edge-colorings of some small subgraphsMar 04 2008Sep 20 2012Let $f(n,p,q)$ be the minimum number of colors necessary to color the edges of $K_n$ so that every $K_p$ is at least $q$-colored. We improve current bounds on the {7/4}n-3$, slightly improving the bound of Axenovich. We make small improvements on bounds ... More
Simple Wriggling is Hard unless You Are a Fat HippoMay 28 2010We prove that it is NP-hard to decide whether two points in a polygonal domain with holes can be connected by a wire. This implies that finding any approximation to the shortest path for a long snake amidst polygonal obstacles is NP-hard. On the positive ... More
The method of dynamic projection operators in the theory of hyperbolic systems of partial differential equations with variable coefficientsMar 30 2014We consider a generalization of the projecting operators method for the case of Cauchy problem for systems of 1D evolution differential equations of first order with variable coefficients. It is supposed that the coefficients dependence on the only variable ... More
Matter Effects on Neutrino Oscillations in Long Baseline ExperimentsFeb 14 2000May 19 2000We calculate matter effects on neutrino oscillations relevant for long baseline experiments. In particular, we compare the results obtained with constant density along the neutrino path versus results obtained by incorporating the actual density profiles ... More
Geodesic motion of test particles in Korkina-Grigoryev metricNov 22 2016We study the geodesic structure of the Korkina-Grigoryev spacetime. The corresponding metric is a generalization of the Schwarzschild geometry to the case involving a massless scalar field. We investigate the relation between the angular momentum of the ... More
A Scheme for Approximating Probabilistic InferenceFeb 06 2013This paper describes a class of probabilistic approximation algorithms based on bucket elimination which offer adjustable levels of accuracy and efficiency. We analyze the approximation for several tasks: finding the most probable explanation, belief ... More
Characterization of max-continuous local martingales vanishing at infinityDec 03 2014Sep 30 2016We provide a characterization of the family of non-negative local martingales that have continuous running supremum and vanish at infinity. This is done by describing the class of random times that identify the times of maximum of such processes. In this ... More
Hedging of claims with physical delivery under convex transaction costsOct 11 2008We study superhedging of contingent claims with physical delivery in a discrete-time market model with convex transaction costs. Our model extends Kabanov's currency market model by allowing for nonlinear illiquidity effects. We show that an appropriate ... More
Risk measures for processes and BSDEsApr 17 2013The paper analyzes risk assessment for cash flows in continuous time using the notion of convex risk measures for processes. By combining a decomposition result for optional measures, and a dual representation of a convex risk measure for bounded \cd ... More
Random walks in $(\mathbb{Z}_+)^2$ with non-zero drift absorbed at the axesMar 31 2009Spatially homogeneous random walks in $(\mathbb{Z}_{+})^{2}$ with non-zero jump probabilities at distance at most 1, with non-zero drift in the interior of the quadrant and absorbed when reaching the axes are studied. Absorption probabilities generating ... More
Time-Periodic Second-Order Hyperbolic Equations: Fredholmness, Regularity, and Smooth DependenceNov 20 2014The paper concerns the general linear one-dimensional second-order hyperbolic equation $$ \partial^2_tu - a^2(x,t)\partial^2_xu + a_1(x,t)\partial_tu + a_2(x,t)\partial_xu + a_3(x,t)u=f(x,t), \quad x\in(0,1) $$ with periodic conditions in time and Robin ... More
Observables Generalizing Positive Operator Valued MeasuresDec 01 2012We discuss a generalization of POVM which is used in quantum-like modeling of mental processing.