Results for "Ekaterina Pomjakushina"

total 403took 0.12s
Microscopic studies of the normal and superconducting state of Ca3Ir4Sn13May 03 2013Oct 15 2013We report on muon spin rotation (muSR) studies of the superconducting and magnetic properties of the ternary intermetallic stannide Ca3Ir4Sn13. This material has recently been the focus of intense research activity due to a proposed interplay of ferromagnetic ... More
Improved Photoelectrochemical Water Splitting of CaNbO2N Photoanodes by Co-Pi Photodeposition and Surface PassivationFeb 20 2019Photoelectrochemical solar water splitting is a promising approach to convert solar energy into sustainable hydrogen fuel using semiconductor electrodes. Due to their visible light absorption properties, oxynitrides have shown to be attractive photocatalysts ... More
Spin-Polarized Quantum Well States on Bi$_{2-x}$Fe$_x$Se$_3$Jan 22 2015Low temperature scanning tunneling microscopy is used to image the doped topological insulator Bi$_{2-x}$Fe$_x$Se$_3$. Interstitial Fe defects allow the detection of quasiparticle interference (QPI), and the reconstruction of the empty state band structure. ... More
Magnetothermoelectric effects in Fe{1+d}Te{1-x}Se{x}Sep 04 2012We report resistivity as well as the Hall, Seebeck and Nernst coefficients data for Fe{1+d}Te{1-x}Se{x} single crystals with x = 0, 0.38, and 0.40. In the parent compound Fe{1.04}Te we observe at Tn = 61 K a sudden change of all quantities studied, which ... More
Synthesis, crystal structure and chemical stability of the superconductor FeSe_{1-x}May 13 2009We report on a comparative study of the crystal structure and the magnetic properties of FeSe1-x (x= 0.00 - 0.15) superconducting samples by neutron powder diffraction and magnetization measurements. The samples were synthesized by two different methods: ... More
Novel synthesis method of nonstoichiometric Na2-xIrO3. Crystal structure, transport and magnetic propertiesDec 21 2015Transition metal oxides with 4d or 5d metals are of great interest due to the competing interactions, of the Coulomb repulsion and the itineracy of the d-electrons, opening a possibility of building new quantum ground states. Particularly the 5d metal ... More
Spin dynamics of edge-sharing spin chains in SrCa13Cu24O41Jan 07 2019The low-energy magnetic excitation from the highly Ca-doped quasi-one-dimensional magnet SrCa13Cu24O41 was studied in the magnetic ordered state by using inelastic neutron scattering. We observed the gapless spin-wave excitation, dispersive along the ... More
New synthesis route and magnetic structure of Tm2Mn2O7 - pyrochloreJul 10 2015In this work we present a new chemical route to synthesize Tm2Mn2O7 pyrochlore, a compound which is thermodynamically unstable at ambient pressure. Differently from the reported in the past high pressure synthesis of the same compound applying oxides ... More
Varietes de Fano et morphismes: notes d'un mini-coursNov 23 2004This is not a research article. This is a partial version of a mini-cours which I gave at a meeting of the ACI Jeunes Chercheurs "Dynamique des applications polynomiales" in Toulouse in november 2004. This text includes two parts of that mini-cours: the ... More
Some remarks on morphisms between Fano threefoldsMay 11 2004May 21 2004Let $X$, $Y$ be Fano threefolds of Picard number one and such that the ample generators of Picard groups are very ample. Let $X$ be of index one and $Y$ be of index two. It is shown that the only morphisms from $X$ to $Y$ are double coverings. In fact ... More
On the notion of scalar product for finite-dimensional diffeological vector spacesJul 14 2015It is known that the only finite-dimensional diffeological vector space that admits a diffeologically smooth scalar product is the standard space of appropriate dimension. In this note we consider a way to circumnavigate this issue, by introducing a notion ... More
Diffeological De Rham operatorsMar 04 2017We consider the notion of the De Rham operator on finite-dimensional diffeological spaces such that the diffeological counterpart \Lambda^1(X) of the cotangent bundle, the so-called pseudo-bundle of values of differential 1-forms, has bounded dimension. ... More
Some applications of p-adic uniformization to algebraic dynamicsJul 07 2014This is not a research paper, but a survey submitted to a proceedings volume.
A remark on a question of Beauville about lagrangian fibrationsOct 13 2011Apr 22 2012This note is a proof of the fact that a lagrangian torus on a hyperkaehler fourfold is always a fiber of an almost holomorphic lagrangian fibration.
Modeling and Estimation of the Risk When Choosing a ProviderMar 16 2016The paper provides an algorithm for the risk estimation when a company selects an outsourcing service provider for innovation product. Calculations are based on expert surveys conducted among customers and among providers of outsourcing. The surveys assessed ... More
Asymptotic Behavior of Local Particles Numbers in Branching Random WalkMar 11 2012Critical catalytic branching random walk on d-dimensional integer lattice is investigated for all d. The branching may occur at the origin only and the start point is arbitrary. The asymptotic behavior, as time grows to infinity, is determined for the ... More
Diffeological vector pseudo-bundlesSep 10 2015We consider a diffeological counterpart of the notion of a vector bundle (we call this counterpart a pseudo-bundle, although in the other works it is called differently; among the existing terms there are a "regular vector bundle" of Vincent and "diffeological ... More
Mirror magnetic field and its impact on dark matter distribution in galaxiesFeb 12 2019We obtain the value of the mirror magnetic field during different stages of cosmological evolution. We consider the magnetic field generation in the radiation-dominated era and the post-recombination epoch. We also estimate its galactic low-scale value ... More
A computation of invariants of a rational self-mapJul 26 2007I compute the dynamical degrees in C. Voisin's example of a rational self-map of the variety of lines on a cubic fourfold.
Factorization of Darboux transformations of arbitrary order for 2D Schroedinger operatorsApr 26 2013May 02 2016We give a proof of Darboux's conjecture that every Darboux transformation of arbitrary order of a 2D Schr\"odinger type operator can be factorized into Darboux transformations of order one. The proof is constructive. The result is obtained in the framework ... More
Invertible Darboux TransformationsOct 02 2012Jan 04 2013For operators of many different kinds it has been proved that (generalized) Darboux transformations can be built using so called Wronskian formulae. Such Darboux transformations are not invertible in the sense that the corresponding mappings of the operator ... More
$X$- and $Y$-invariants of Linear Partial Differential Operators in the plane (In Russian)Oct 17 2010Aug 19 2011We consider a classical problem of Computer Algebra: symbolic solution of PDEs. We transform the famous Darboux theorems on differential transformations of hyperbolic operator into the space of invariants. We introduce a new idea -- $X$- and $Y$-invariants ... More
Multilinear algebra in the context of diffeologyApr 30 2015Dec 22 2015This note is dedicated to some details of multilinear algebra on diffeological vector spaces; most of them are the expected corollaries of standard constructions and various facts of diffeology collected elsewhere. Most of the attention is paid to the ... More
Generalized Mom-structures and ideal triangulations of 3-manifolds with non-spherical boundaryMay 03 2010Mar 17 2011The so-called Mom-structures on hyperbolic cusped 3-manifolds without boundary were introduced by Gabai, Meyerhoff, and Milley, and used by them to identify the smallest closed hyperbolic manifold. In this work we extend the notion of a Mom-structure ... More
Pseudo-bundles of exterior algebras as diffeological Clifford modulesApr 17 2016Feb 09 2017We consider the diffeological pseudo-bundles of exterior algebras, and the Clifford action of the corresponding Clifford algebras, associated to a given finite-dimensional and locally trivial diffeological vector pseudo-bundle, as well as the behavior ... More
Diffeological Levi-Civita connectionsJan 18 2017A diffeological connection on a diffeological vector pseudo-bundle is defined just the usual one on a smooth vector bundle; this is possible to do, because there is a standard diffeological counterpart of the cotangent bundle. On the other hand, there ... More
Proof of the Completeness of Darboux Wronskian Formulae for Order TwoNov 05 2011Jun 02 2012Darboux Wronskian formulas allow to construct Darboux transformations, but Laplace transformations, which are Darboux transformations of order one cannot be represented this way. It has been a long standing problem on what are other exceptions. In our ... More
Invariants for Darboux transformations of Arbitrary Order for $D_x D_y +aD_x + bD_y +c$Oct 10 2012We develop the method of regularized moving frames of Fels and Olver to obtain explicit general formulas for the basis invariants that generate all the joint differential invariants, under gauge transformations, for the operators [\o{L}=D_xD_y +a(x,y) ... More
Multiple Factorizations of Bivariate Linear Partial Differential OperatorsOct 18 2010We study the case when a bivariate Linear Partial Differential Operator (LPDO) of orders three or four has several different factorizations. We prove that a third-order bivariate LPDO has a first-order left and right factors such that their symbols are ... More
Refinement of Two-Factor Factorizations of a Linear Partial Differential Operator of Arbitrary Order and DimensionJan 12 2010Oct 12 2010Given a right factor and a left factor of a Linear Partial Differential Operator (LPDO), under which conditions we can refine these two-factor factorizations into one three-factor factorization? This problem is solved for LPDOs of arbitrary order and ... More
The Hitting Times with Taboo for a Random Walk on an Integer LatticeJul 06 2011For a symmetric, homogeneous and irreducible random walk on d-dimensional integer lattice Z^d, having zero mean and a finite variance of jumps, we study the passage times (with possible infinite values) determined by the starting point x, the hitting ... More
Differential 1-forms on diffeological spaces and diffeological gluingMay 24 2016This paper aims to describe the behavior of diffeological differential 1-forms under the operation of gluing of diffeological spaces along a smooth map (the results obtained actually apply to all k-forms with k>0). In the diffeological context, two constructions ... More
Diffeological vector pseudo-bundles, and diffeological pseudo-metrics on them as substitutes for Riemannian metricsJan 02 2016Although our main interest here is developing an appropriate analog, for diffeological vector pseudo-bundles, of a Riemannian metric, a significant portion is dedicated to continued study of the gluing operation for pseudo-bundles introduced in arXiv:1509.03023. ... More
Diffeological connections on diffeological vector pseudo-bundlesNov 23 2016We consider one possible definition of a diffeological connection on a diffeological vector pseudo-bundle. It is different from the one proposed in [7] and is in fact simpler, since it is obtained by a straightforward adaption of the standard definition ... More
Profinite completions of some groups acting on treesNov 09 2004Nov 16 2004We investigate the profinite completions of a certain family of groups acting on trees. It turns out that for some of the groups considered, the completions coincide with the closures of the groups in the full group of tree automorphisms. However, we ... More
On endomorphisms of projective bundlesSep 18 2002Let $X$ be a complex projective bundle. We prove that $X$ admits an endomorphism of degree $>1$ and commuting with the projection to the base, if and only if $X$ trivializes after a finite covering. When $X$ is the projectivization of a vector bundle ... More
On morphisms onto quadricsJun 06 2006It is proved that the degree of a morphism from a smooth projective n-fold with Picard number one to a smooth n-quadric is bounded (provided, of course, that n is at least three). Actually it has been proved some years ago, but I have never written down ... More
Taylor Series for Adomian Decomposition MethodApr 10 2011In the paper we analyse the exact solutions to scalar PDEs obtained thanks to summable Taylor series provided by Adomian's decomposition method. We propose the modification of the method which makes the calculations of Taylor coefficients easier and more ... More
Pseudo-bundles of exterior algebras as diffeological Clifford modulesApr 17 2016We consider the diffeological pseudo-bundles of exterior algebras, and the Clifford action of the corresponding Clifford algebras, associated to a given finite-dimensional and locally trivial diffeological vector pseudo-bundle, as well as the behavior ... More
Diffeological Clifford algebras and pseudo-bundles of Clifford modulesMay 26 2015Jun 06 2016We consider the diffeological version of the Clifford algebra of a (diffeological) finite-dimensional vector space; we start by commenting on the notion of a diffeological algebra (which is the expected analogue of the usual one) and that of a diffeological ... More
Groups of tree automorphisms as diffeological groupsMay 19 2015Mar 29 2016We consider certain groups of tree automorphisms as so-called diffeological groups. The notion of diffeology, due to Souriau, allows to endow non-manifold topological spaces, such as regular trees that we look at, with a kind of a differentiable structure ... More
Existence of non-preperiodic algebraic points for a rational self-map of infinite orderJul 09 2010Let $X$ be a variety defined over a number field and $f$ be a dominant rational self-map of $X$ of infinite order. We show that $X$ admits many algebraic points which are not preperiodic under $f$. If $f$ were regular and polarized, this would follow ... More
The difference cross sections of unpolarized SIDIS with transverse momentum dependenceJul 22 2014Previously we showed that, based only on C and SU(2) invariance, the difference cross sections of hadrons with opposite charge in SIDIS e+N\to l+h+X is expressed solely in terms of the valence-quark densities and certain non-singlet combinations of FFs. ... More
On an automorphism of $Hilb^{[2]}$ of certain K3 surfacesJul 20 2009An example of potential density of rational points on the second punctual Hilbert scheme of certain K3 surfaces is treated in detail. This is an amplification of some remarks made by O'Grady and Oguiso.
Diffeological connections on diffeological vector pseudo-bundlesNov 23 2016Feb 04 2017We consider one possible definition of a diffeological connection on a diffeological vector pseudo-bundle. It is different from the one proposed in [7] and is in fact simpler, since it is obtained by a straightforward adaption of the standard definition ... More
Diffeological Dirac operators and diffeological gluingJan 24 2017This manuscript attempts to present a way in which the classical construction of the Dirac operator can be carried over to the setting of diffeology. A more specific aim is to describe a procedure for gluing together two usual Dirac operators and to explain ... More
Design of magnetic spirals in layered perovskites: extending the stability range far beyond room temperatureSep 27 2018In insulating materials with ordered magnetic spiral phases, ferroelectricity can emerge due to the breaking of inversion symmetry. This property is of both fundamental and practical interest, in particular with a view to exploiting it in low-power electronic ... More
Structural Evolution of One-dimensional Spin Ladder Compounds Sr14-xCaxCu24O41 with Ca doping and Related Hole Redistribution EvidenceSep 05 2011Incommensurate crystal structures of spin ladder series Sr14-xCaxCu24O41 (x=3, 7, 11, 12.2) were characterized by powder neutron scattering method and refined using the superspace group Xmmm(00{\gamma})ss0 (equivalent to superspace group Fmmm(0,0,1+{\gamma})ss0); ... More
Long Cycle Factorizations : Bijective Computation in the General CaseNov 26 2012Jan 13 2013This paper is devoted to the computation of the number of ordered factorizations of a long cycle in the symmetric group where the number of factors is arbitrary and the cycle structure of the factors is given. Jackson (1988) derived the first closed form ... More
Criteria of measure-preserving for $p$-adic dynamical systems in terms of the van der Put basisOct 16 2012This paper is devoted to (discrete) $p$-adic dynamical systems, an important domain of algebraic and arithmetic dynamics. We consider the following open problem from theory of $p$-adic dynamical systems. Given continuous function $f:Z_p > Z_p.$ Let us ... More
On Kaon production in e+e- and Semi-inclusive DIS reactionsDec 05 2006Jun 04 2007We consider semi-inclusive unpolarized DIS for the production of charged kaons and the different possibilities to test the conventionally used assumptions s-\bar=0 and D_d^{K^+-K^-}=0. The considered tests have the advantage that they do not require any ... More
Logic programming: laxness and saturationAug 27 2016Aug 30 2016A propositional logic program $P$ may be identified with a $P_fP_f$-coalgebra on the set of atomic propositions in the program. The corresponding $C(P_fP_f)$-coalgebra, where $C(P_fP_f)$ is the cofree comonad on $P_fP_f$, describes derivations by resolution. ... More
Using Structural Recursion for CorecursionMar 23 2009We propose a (limited) solution to the problem of constructing stream values defined by recursive equations that do not respect the guardedness condition. The guardedness condition is imposed on definitions of corecursive functions in Coq, AGDA, and other ... More
Classification of catalytic branching processes and structure of the criticality setFeb 14 2015We study a catalytic branching process (CBP) with any finite set of catalysts. This model describes a system of particles where the movement is governed by a Markov chain with arbitrary finite or countable state space and the branching may only occur ... More
On the existence of branched coverings between surfaces with prescribed branch data, IAug 23 2005May 26 2009For the existence of a branched covering Sigma~ --> Sigma between closed surfaces there are easy necessary conditions in terms of chi(Sigma~), chi(Sigma), orientability, the total degree, and the local degrees at the branching points. A classical problem ... More
Criteria of ergodicity for $p$-adic dynamical systems in terms of coordinate functionsMar 23 2013This paper is devoted to the problem of ergodicity of $p$-adic dynamical systems. Our aim is to present criteria of ergodicity in terms of coordinate functions corresponding to digits in the canonical expansion of $p$-adic numbers. The coordinate representation ... More
Collections of parabolic orbits in homogeneous spaces, homogeneous dynamics and hyperkahler geometryApr 13 2016Let $M$ be a hyperk\"ahler manifold with $b_2(M)\geq 5$. We improve our earlier results on the Morrison-Kawamata cone conjecture by showing that the Beauville-Bogomolov square of the primitive MBM classes (i.e. the classes whose orthogonal hyperplanes ... More
About S-\bar s, ΔS-Δ\bar s and D_d^{K+ - K-} in K^\pm Production in SidisJan 11 2008We consider semi-inclusive unpolarized DIS for the production of charged Kaons and the different possibilities, both in LO and NLO, to test the conventionally used assumptions s-\bar s=0, \Delta s-\Delta \bar s=0 and D_d^{K+ - K-}=0. The considered tests ... More
A Strategy for the Analysis of Semi-Inclusive Deep Inelastic ScatteringJul 26 2000Feb 02 2001We present a strategy for the systematic extraction of a vast amount of detailed information on polarized parton densities and fragmentation functions from semi-inclusive deep inelastic scattering l+N -> l+h+X, in both LO and NLO QCD. A method is suggested ... More
Semi-inclusive π^\pm production - tests for independent fragmentation and for polarized quark densitiesJul 07 1999Nov 24 1999We show that measurements of semi-inclusive $\pi^\pm$ asymmetries on $p$ and $n$ with polarized and unpolarized target and beams allow, without any knowledge of the polarized parton densities 1) to test independent fragmentation and SU(2) symmetry for ... More
Tests for Sivers, Boer-Mulders and transversity distributions in difference cross sections in SIDISDec 04 2015Dec 11 2015A major experimental program is presently underway to determine the Sivers, Boer-Mulders and transversity distributions, vital for understanding the internal structure of the nucleon. To this end we consider the Sivers, Boer-Mulders and transversity azimuthal ... More
On the top-quark polarization and how to measure itOct 02 1997The top quark is expected to decay as a free particle with definite momentum and polarization. Here we consider the possibilities to obtain information about its polarization through the energy and angular distributions of the b-quarks from the decay ... More
HoTT formalisation in Coq: Dependency Graphs \& ML4PGMar 11 2014This note is a response to Bas Spitter's email of 28 February 2014 about ML4PG: "We (Jason actually) are adding dependency graphs to our HoTT library: https://github.com/HoTT/HoTT/wiki I seem to recall that finding the dependency graph was a main obstacle ... More
A Literature Survey on Empirical Evidence in Software EngineeringApr 03 2013Context: Software Engineering research makes use of collections of software artifacts (corpora) to derive empirical evidence from. Goal: To improve quality and reproducibility of research, we need to understand the characteristics of used corpora. Method: ... More
Fibrations meromorphes sur certaines varietes de classe canonique trivialeOct 14 2005Nov 16 2006Motivated by an example, due to Voisin, of a smooth simply-connected projective variety with trivial canonical class and cyclic Picard group, admitting a meromorphic endomorphism of high degree, we study meromorphic fibrations on certain varieties with ... More
Classification of multidimensional Darboux transformations: first order and continued typeMay 14 2016Oct 07 2016We analyze Darboux transformations in very general settings for multi-dimensional linear partial differential operators. We consider all known types of Darboux transformations, and present a new type. We obtain a full classification of all operators that ... More
Random graph ensembles with many short loopsApr 10 2014Networks observed in the real world often have many short loops. This violates the tree-like assumption that underpins the majority of random graph models and most of the methods used for their analysis. In this paper we sketch possible research routes ... More
Explicit monomial expansions of the generating series for connection coefficientsNov 27 2011This paper is devoted to the explicit computation of generating series for the connection coefficients of two commutative subalgebras of the group algebra of the symmetric group, the class algebra and the double coset algebra. As shown by Hanlon, Stanley ... More
Subcritical catalytic branching random walk with finite or infinite variance of offspring numberDec 06 2012Subcritical catalytic branching random walk on d-dimensional lattice is studied. New theorems concerning the asymptotic behavior of distributions of local particles numbers are established. To prove the results different approaches are used including ... More
Performance evaluation of modulation methods: a combinatorial approachJan 16 2001This paper is devoted to the presentation of a combinatorial approach for analyzing the performance of an important modulation protocol used in mobile telecommunications. We show in particular that a fundamental formula, in this context, is in fact highly ... More
Matrix Ordered Operator AlgebrasApr 12 2007Apr 22 2007We study the question when for a given *-algebra $\mathcal{A}$ a sequence of cones $C_n\in M_n(\mathcal{A})$ can be realized as cones of positive operators in a faithful *-representation of $\mathcal{A}$ on a Hilbert space. A characterization of operator ... More
Growth of matrix products and mixing properties of the horocycle flowAug 18 2010\noindent In [1] L. Polterovich and Z. Rudnick considered the behavior of a one-parameter subgroup of a Lie group under the influence of a sequence of kicks. Among others they raise the following problem: {\it is the horocycle flow stably quasi-mixing ... More
Rational curves on hyperkahler manifoldsJan 02 2014Let $M$ be an irreducible holomorphically symplectic manifold. We show that all faces of the Kahler cone of $M$ are hyperplanes $H_i$ orthogonal to certain homology classes, called monodromy birationally minimal (MBM) classes. Moreover, the Kahler cone ... More
Teichmuller space for hyperkahler and symplectic structuresMar 04 2015Let S be an infinite-dimensional manifold of all symplectic, or hyperkahler, structures on a compact manifold M, and $Diff_0$ the connected component of its diffeomorphism group. The quotient $S/\Diff_0$ is called the Teichmuller space of symplectic (or ... More
Obstacles to the Factorization of Linear Partial Differential Operators into Several FactorsOct 13 2010We consider algorithms for the factorization of linear partial differential operators. We introduce several new theoretical notions in order to simplify such considerations. We define an obstacle and a ring of obstacles to factorizations. We derive some ... More
On Non-singlets in Kaon Production in Semi-inclusive DIS reactionsMar 12 2007We consider semi-inclusive unpolarized DIS for the production of charged kaons and the different possibilities, both in LO and NLO, to test the conventionally used assumptions $s-\bar s=0$ and $D_d^{K^+-K^-}=0$. The considered tests have the advantage ... More
Non-singlets in Semi-inclusive DIS and inclusive e+e- annihilationDec 06 2005We show that non-singlets in semi-inclusive DIS with pi^\pm determine without assumptions Delta u_V, Delta d_V and D_u^{\pi+ - pi-}. Non-singlets in SIDIS and inclusive e+e- -annihilation with K^\pm determine (s-bar s) and (Delta s-Delta bar s), but an ... More
Statistical Proof Pattern Recognition: Automated or Interactive?Mar 05 2013In this paper, we compare different existing approaches employed in data mining of big proof libraries in automated and interactive theorem proving.
ML4PG in Computer Algebra verificationFeb 26 2013May 24 2013ML4PG is a machine-learning extension that provides statistical proof hints during the process of Coq/SSReflect proof development. In this paper, we use ML4PG to find proof patterns in the CoqEAL library -- a library that was devised to verify the correctness ... More
Darboux transformation of boundary conditions of regular Dirac Sturm--Liouville problemNov 11 2007It is shown that boundary conditions of the Darboux transformed Dirac Sturm--Liouville problem are always zero-valued independently on boundary conditions of initial problem.
Morrison-Kawamata cone conjecture for hyperkahler manifoldsAug 18 2014Oct 26 2014Let $M$ be a simple holomorphically symplectic manifold, that is, a simply connected holomorphically symplectic manifold of Kahler type with $h^{2,0}=1$. We prove that the group of holomorphic automorphisms of $M$ acts on the set of faces of its Kahler ... More
On families of lagrangian tori on hyperkaehler manifoldsMar 04 2013This is a note on Beauville's problem (solved by Greb, Lehn and Rollenske in the non-algebraic case and by Hwang and Weiss in general) whether a lagrangian torus on an irreducible holomorphic symplectic manifold is a fiber of a lagrangian fibration. We ... More
Integrable cosmological models with non-minimal coupling and bounce solutionsNov 07 2016We remind the way to obtain integrable models with non-minimally coupled scalar fields. We are interesting to models with bounce solutions and compare bounce solutions in two known integrable models. We show that only one model has a bounce solution that ... More
Secure cloud computations: Description of (fully)homomorphic ciphers within the P-adic model of encryptionMar 24 2016In this paper we consider the description of homomorphic and fully homomorphic ciphers in the $p$-adic model of encryption. This model describes a wide class of ciphers, but certainly not all. Homomorphic and fully homomorphic ciphers are used to ensure ... More
Strong and weak convergence of population size in supercritical catalytic branching processJun 18 2015A general model of catalytic branching process (CBP) with any finite number of catalysis centers in a discrete space is studied. More exactly, it is assumed that particles move in this space according to a specified Markov chain and they may produce offspring ... More
Moments of normally distributed random matrices - Bijective explicit evaluationNov 29 2013This paper is devoted to the distribution of the eigenvalues of $XUYU^t$ where $X$ and $Y$ are given symmetric matrices and $U$ is a random real valued square matrix of standard normal distribution. More specifically we look at its moments, i.e. the mathematical ... More
Centralizer of the elementary subgroup of an isotropic reductive groupDec 01 2010Dec 11 2010Let G be an isotropic reductive algebraic group over a commutative ring R. Assume that, for any maximal ideal M of R, the rank of the relative root system of G_{R_M} is greater or equal than 2. We show that under this assumption the centralizer of E(R) ... More
Waveform Design for Wireless Power TransferMar 31 2016Aug 09 2016Far-field Wireless Power Transfer (WPT) has attracted significant attention in recent years. Despite the rapid progress, the emphasis of the research community in the last decade has remained largely concentrated on improving the design of energy harvester ... More
Complexity and T-invariant of Abelian and Milnor groups, and complexity of 3-manifoldsDec 09 2004We investigate the notion of complexity for finitely presented groups and the related notion of complexity for three-dimensional manifolds. We give two-sided estimates on the complexity of all the Milnor groups (the finite groups with free action on the ... More
Operational Semantics of Resolution and Productivity in Horn Clause LogicApr 14 2016Aug 17 2016This paper presents a study of operational and type-theoretic properties of different resolution strategies in Horn clause logic. We distinguish four different kinds of resolution: resolution by unification (SLD-resolution), resolution by term-matching, ... More
Finiteness of hitting times under tabooOct 26 2013We consider a continuous-time Markov chain with a finite or countable state space. For a site y and subset H of the state space, the hitting time of y under taboo H is defined to be infinite if the process trajectory hits H before y, and the first hitting ... More
On the characteristic foliation on a smooth hypersurface in a holomorphic symplectic fourfoldNov 01 2016Let $X$ be an irreducible holomorphic symplectic fourfold and $D$ a smooth hypersurface in $X$. It follows from a result by Amerik and Campana that the characteristic foliation (that is the foliation given by the kernel of the restriction of the symplectic ... More
Complexity of links in 3-manifoldsOct 07 2008We introduce a natural-valued complexity c(X) for pairs X=(M,L), where M is a closed orientable 3-manifold and L is a link contained in M. The definition employs simple spines, but for well-behaved X's we show that c(X) equals the minimal number of tetrahedra ... More
Polynomial properties of Jack connection coefficients and generalization of a result by DénesNov 30 2013Sep 14 2014This article is devoted to the computation of Jack connection coefficients, a generalization of the connection coefficients of two classical commutative subalgebras of the group algebra of the symmetric group: the class algebra and the double coset algebra. ... More
Classification of multidimensional Darboux transformations: first order and continued typeMay 14 2016Sep 26 2016We analyze Darboux transformations in very general settings for multi-dimensional linear partial differential operators. We consider all known types of Darboux transformations, and present a new type. We obtain a full classification of all operators that ... More
On the existence of branched coverings between surfaces with prescribed branch data, IINov 09 2006For a given branched covering between closed connected surfaces, there are several easy relations one can establish between the Euler characteristics of the surfaces, their orientability, the total degree, and the local degrees at the branching points, ... More
Transformation of auto-Bäcklund type for hyperbolic generalization of Burgers equationSep 06 2007Oct 17 2008We consider the hyperbolic generalization of Burgers equation with polynomial source term. The transformation of auto-B\"{a}cklund type was found. Application of the results is shown in the examples, where the pair of two stationary solutions produces ... More
Hyperbolic geometry of the ample cone of a hyperkahler manifoldNov 07 2015Let $M$ be a compact hyperkahler manifold with maximal holonomy (IHS). The group $H^2(M, R)$ is equipped with a quadratic form of signature $(3, b_2-3)$, called Bogomolov-Beauville-Fujiki (BBF) form. This form restricted to the rational Hodge lattice ... More
Doppler cooling of three-level $Λ$-systems by coherent pulse trainsMar 08 2012Sep 29 2012We explore the possibility of decelerating and Doppler cooling an ensemble of tree-level $\Lambda$-type atoms by a coherent train of short, non-overlapping laser pulses. We show that $\Lambda$-atoms can be Doppler cooled without additional repumping of ... More
The dynamics of three-level $Λ$-type system driven by the trains of ultrashort laser pulsesFeb 29 2012May 20 2012We study the dynamics of a tree-level $\Lambda$-type atoms driven by a coherent train of short, non-overlapping laser pulses.We derive analytical non-perturbative expressions for density matrix by approximating pulses by delta-function.We demonstrate ... More