Results for "Roman-Pascal Riwar"

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Efficient quasiparticle traps with low dissipation through gap engineeringJul 10 2019Quasiparticles represent an intrinsic source of perturbation for superconducting qubits, leading to both dissipation of the qubit energy and dephasing. Recently, it has been shown that normal-metal traps may efficiently reduce the quasiparticle population ... More
Readout of relaxation rates by nonadiabatic pumping spectroscopyFeb 09 2016We put forward nonadiabatic charge pumping as a method for accessing the different charge relaxation rates as well as the relaxation rates of excited orbital states in double-quantum-dot setups, based on extremely size-limited quantum dots and dopant ... More
Strong effects of weak ac driving in short superconducting junctionsOct 14 2014We study a short superconducting junction subject to a dc and ac phase bias. The ac modulation changes the occupation of the Andreev bound states formed at the constriction by transitions between bound states and the continuum. In a short junction, the ... More
Multi-terminal Josephson junctions as topological materialsMar 23 2015Topological materials and their unusual transport properties are now at the focus of modern experimental and theoretical research. Their topological properties arise from the bandstructure determined by the atomic composition of a material and as such ... More
Topological transconductance quantization in a four-terminal Josephson junctionDec 16 2016Sep 30 2017Recently we predicted that the Andreev bound state spectrum of 4-terminal Josephson junctions may possess topologically protected zero-energy Weyl singularities, which manifest themselves in a quantized transconductance in units of $4e^2/h$ when two of ... More
Control of Andreev bound state population and related charge-imbalance effectJul 02 2014Motivated by recent experimental research, we study the processes in an ac driven superconducting constriction whereby one quasiparticle is promoted to the delocalized states outside the superconducting gap. We demonstrate that with these processes one ... More
Cross-correlations of coherent multiple Andreev reflectionsNov 01 2015We use the Landauer-B\"uttiker scattering theory for electronic transport to calculate the current cross-correlations in a voltage-biased three-terminal junction with all superconducting leads. At low bias voltage, when charge transport is due to coherent ... More
On non-repetitive sequences of arithmetic progressions:the cases $k \in \{4,5,6,7,8\}$Oct 02 2018A $d$-subsequence of a sequence $\varphi = x_1\dots x_n$ is a subsequence $x_i x_{i+d} x_{i+2d} \dots$, for any positive integer $d$ and any $i$, $1 \le i \le n$. A \textit{$k$-Thue sequence} is a sequence in which every $d$-subsequence, for $1 \le d ... More
On-Surface Hydrogen-Induced Covalent Coupling of Polycyclic Aromatic Hydrocarbons via a Superhydrogenated IntermediateApr 26 2019The activation and subsequent covalent coupling of polycyclic aromatic hydrocarbons (PAHs) are of great interest in fields like chemistry, energy, biology, or health, among others. However, this is not a trivial process. So far, it is based on the use ... More
Engineering of robust topological quantum phases in graphene nanoribbonsMay 17 2018Here we present a flexible strategy to realize robust nanomaterials exhibiting valence electronic structures whose fundamental physics is described by the SSH-Hamiltonian. These solid-state materials are realized using atomically precise graphene nanoribbons ... More
Structure-dependent electrical properties of graphene nanoribbon devices with graphene electrodesFeb 08 2019Graphene nanoribbons (GNRs) are a novel and intriguing class of materials in the field of nanoelectronics, since their properties, solely defined by their width and edge type, are controllable with high precision directly from synthesis. Here we study ... More
Deformed Dolan-Grady relations in quantum integrable modelsApr 20 2004Dec 15 2004A new hidden symmetry is exhibited in the reflection equation and related quantum integrable models. It is generated by a dual pair of operators $\{\textsf{A}, \textsf{A}^*\}\in{\cal A}$ subject to $q-$deformed Dolan-Grady relations. Using the inverse ... More
Scientific Pluralism: the battle of High Temperature SuperconductivityOct 29 2015The early development of conflicting theories (i.e. one aspect of scientific pluralism) about the microscopic mechanism of High Temperature Superconductivity is described. The biographical roots of this diversity are stressed, as well as its subjective/objective ... More
The available-enthalpy (flow-exergy) cycle. Part-I: introduction and basic equationsMar 22 2014A diagnostic package is derived from the concept of specific available enthalpy, leading to the definition of a local and complete energy cycle. It is useful to understand the transformations of energy occurring at any particular pressure level or pressure ... More
Une grammaire formelle du créole martiniquais pour la génération automatiqueOct 07 2008In this article, some first elements of a computational modelling of the grammar of the Martiniquese French Creole dialect are presented. The sources of inspiration for the modelling is the functional description given by Damoiseau (1984), and Pinalie's ... More
The attractor structure of logarithmic iterations in the complex planeDec 29 2010We use the methods of empirical mathematics to show that iterative logarithmic operations will result in an attractor point on the complex plane. Moreover, we demonstrate that different bases converge onto different attractors. Finally, we elicit the ... More
On the $\bar{\mathbb F}_l$-cohomology of a simple unitary Shimura varietyDec 07 2015Apr 06 2016We study the torsion cohomology classes of Shimura varieties of type Kottwitz-Harris-Taylor and we show that " up to an arbitrary place " one can raise them to an automorphic representation. In application, to any mod $l$ system of Hecke eigenvalues appearing ... More
A Semantics-based Communication System for Dysphasic SubjectsMar 12 1997Dysphasic subjects do not have complete linguistic abilities and only produce a weakly structured, topicalized language. They are offered artificial symbolic languages to help them communicate in a way more adapted to their linguistic abilities. After ... More
Independent Component Analysis and estimation of a quadratic functionalMay 31 2006Sep 10 2006Independent component analysis (ICA) is linked up with the problem of estimating a non linear functional of a density, for which optimal estimators are well known. The precision of ICA is analyzed from the viewpoint of functional spaces in the wavelet ... More
Réseaux d'induction des représentations elliptiques de Lubin-TateMay 19 2008We study the reduction modulo $l$ of some elliptic representations; for each of these representations, we give a particular lattice naturally obtained by parabolic induction in giving the graph of extensions between its irreducible sub-quotient of its ... More
Brighter than the sun: Powerscape visualizations illustrate power needs in neuroscience and psychologyDec 31 2015Participant needs to achieve a given power are frequently underestimated. This is particularly problematic when effect sizes are small, such as is common in neuroscience and psychology. We provide tools to make these demands immediately obvious in the ... More
Crossover in the log-gamma polymer from the replica coordinate Bethe AnsatzJul 12 2017The coordinate Bethe Ansatz solution of the log-gamma polymer is extended to boundary conditions with one fixed end and the other attached to one half of a one-dimensional lattice. The large-time limit is studied using a saddle-point approximation,and ... More
The parameters uncertainty inflation fallacyNov 14 2016Aug 24 2017Statistical estimation of the prediction uncertainty of physical models is typically hindered by the inadequacy of these models due to various approximations they are built upon. The prediction errors due to model inadequacy can be handled either by correcting ... More
Steady states in a non-conserving zero-range process with extensive rates as a model for the balance of selection and mutationApr 11 2019Jun 19 2019We consider a non-conserving zero-range process with hopping rate proportional to the number of particles at each site. Particles are added to the system with a site-dependent creation rate, and removed from the system with a uniform annihilation rate. ... More
Topology of the mesoscale connectome of the mouse brainNov 12 2018Dec 21 2018The wiring diagram of the mouse brain has recently been mapped at a mesoscopic scale in the Allen Mouse Brain Connectivity Atlas. Axonal projections from brain regions were traced using green fluoresent proteins. The resulting data were registered to ... More
Quantum centipedes with strong global constraintAug 16 2016Apr 26 2017A centipede made of $N$ quantum walkers on a one-dimensional lattice is considered. The distance between two consecutive legs is either one or two lattice spacings, and a global constraint is imposed: the maximal distance between the first and last leg ... More
Automorphic congruences and torsion in the cohomology of a simple unitary Shimura varietyOct 31 2016Jan 02 2017We first give a relative flexible process to construct torsion cohomology classes for Shimura varieties of Kottwitz-Harris-Taylor type with coefficient in a non too regular local system. We then prove that associated to each torsion cohomology class, ... More
On the stability of a class of non-monotonic systems of parallel queuesDec 14 2015We investigate, under general stationary ergodic assumptions, the stability of systems of $S$ parallel queues in which any incoming customer joins the queue of the server having the $p+1$-th shortest workload ($p < S$), or a free server if any. This change ... More
Equivariant Cohomology and Localization Formula in SupergeometryFeb 04 2004Let G be a compact Lie group. Let M be a smooth G-manifold and V --> M be an oriented G-equivariant vector bundle. One defines the spaces of equivariant forms with generalized coefficients on V and M. An equivariant Thom form $\theta$ on V is a compactly ... More
Quarkonium measurements in nucleus--nucleus collisions with ALICEJul 20 2018Quarkonia, i.e. bound states of $b\bar{b}$ and $c\bar{c}$ quarks, are powerful observables to study the properties of nuclear matter under extreme conditions. The formation of a Quark-Gluon Plasma (QGP), which is predicted by lattice QCD calculations ... More
The first and second order approximations of the third-law moist-air entropy potential temperatureJan 23 2019May 27 2019It is important to be able to calculate the moist-air entropy of the atmosphere with precision. A potential temperature has already been defined from the third law of thermodynamics for this purpose. However, a doubt remains as to whether this entropy ... More
Persitence of non degeneracy: a local analog of Ihara's lemmaOct 14 2018Persitence of non degeneracy is a phenomenon which appears in the theory of $\overline{\mathbb Q}_l$-representations of the linear group: every irreducible submodule of the restriction to the mirabolic subgroup of an non degenerate irreducible representation ... More
Torsion classes in the cohomology of KHT Shimura varietiesDec 19 2017A particular case of Bergeron-Venkatesh's conjecture predicts that torsion classes in the cohomology of Shimura varieties are rather rare. According to this and for Kottwitz-Harris-Taylor type of Shimura varieties, we first associate to each such torsion ... More
Tetramers of two heavy and two light bosonsFeb 17 2018This article considers the bound states of two heavy and two light bosons, when a short-range force attracts the bosons of different mass, and a short-range force repel the light bosons. The existence of such four-body bound states results from the competition ... More
Root Separation for TrinomialsSep 11 2017Oct 25 2018We give a separation bound for the complex roots of a trinomial $f \in \mathbb{Z}[X]$. The logarithm of the inverse of our separation bound is polynomial in the size of the sparse encoding of $f$; in particular, it is polynomial in $\log (\deg f)$. It ... More
Comprehensive Feature-Based Landscape Analysis of Continuous and Constrained Optimization Problems Using the R-Package flaccoAug 17 2017Choosing the best-performing optimizer(s) out of a portfolio of optimization algorithms is usually a difficult and complex task. It gets even worse, if the underlying functions are unknown, i.e., so-called Black-Box problems, and function evaluations ... More
Mirabolic group, ramified Newton stratification and cohomology of Lubin-Tate spacesNov 07 2016Mar 26 2019In my 2009 paper at Inventiones, we determine the cohomology of Lubin-Tate spaces globally using the comparison theorem of Berkovich by computing the fibers at supersingular points of the perverse sheaf of vanishing cycle $\Psi$ of some Shimura variety ... More
Comments on "Isentropic Analysis of a Simulated Hurricane"Jul 14 2016This paper describes Comments to the paper of Mrowiec et al. published in the J. Atmos. Sci. in May 2016 (Vol 73, Issue 5, pages 1857-1870) and entitled "Isentropic analysis of a simulated hurricane". It is explained that the plotting of isentropic surfaces ... More
The battle of High Temperature SuperconductivityOct 29 2015Dec 02 2016The early development of conflicting theories about the microscopic mechanism of High Temperature Superconductivity is described. The biographical roots of this diversity are stressed, as well as its subjective/objective roots. This study of a specific ... More
Comments on "MSE minus CAPE is the True Conserved Variable for an Adiabatically Lifted Parcel"Sep 30 2015Dec 06 2015In a recent paper, Romps (JAS, vol.72, p.3639-3646, 2015, hereafter R15) argues that the moist-air static energy (MSE) is only approximately conserved for an adiabatically lifted parcel, and that the quantity "MSE - CAPE" could be used as a true conserved ... More
Speed and fluctuations of N-particle branching Brownian motion with spatial selectionApr 02 2013Jun 19 2018We consider branching Brownian motion on the real line with the following selection mechanism: Every time the number of particles exceeds a (large) given number $N$, only the $N$ right-most particles are kept and the others killed. After rescaling time ... More
Kondo screening cloud in a double-quantum dot systemFeb 16 2005We analyze the transport properties of two artificial magnetic impurities coupled togethervia a tunable RKKY interaction mediated by conduction electrons of a finite size one dimensional wire. We show that the sign of the RKKY interaction can be controlled ... More
Construction of a stationary FIFO queue with impatient customersFeb 18 2008In this paper, we study the stability of queues with impatient customers. Under general stationary ergodic assumptions, we first provide some conditions for such a queue to be regenerative (i.e. to empty a.s. an infinite number of times). In the particular ... More
On Hofmann's bilinear estimateDec 17 2008May 17 2009Using the framework of a previous article joint with Axelsson and McIntosh, we extend to systems two results of S. Hofmann for real symmetric equations and their perturbations going back to a work of B. Dahlberg for Laplace's equation on Lipschitz domains, ... More
Independent Component Analysis by WaveletsJun 29 2005Oct 20 2005We propose an ICA contrast based on the density estimation of the observed signal and its marginals by means of wavelets. The risk of the associated moment estimator is linked with approximation properties in Besov spaces. It is shown to converge faster ... More
A Chart-Parsing Algorithm for Efficient Semantic AnalysisSep 02 2002In some contexts, well-formed natural language cannot be expected as input to information or communication systems. In these contexts, the use of grammar-independent input (sequences of uninflected semantic units like e.g. language-independent icons) ... More
Modelling Semantic Association and Conceptual Inheritance for Semantic AnalysisSep 15 2001Allowing users to interact through language borders is an interesting challenge for information technology. For the purpose of a computer assisted language learning system, we have chosen icons for representing meaning on the input interface, since icons ... More
A Layered Grammar Model: Using Tree-Adjoining Grammars to Build a Common Syntactic Kernel for Related DialectsOct 07 2008This article describes the design of a common syntactic description for the core grammar of a group of related dialects. The common description does not rely on an abstract sub-linguistic structure like a metagrammar: it consists in a single FS-LTAG where ... More
Default reasoning over domains and concept hierarchiesSep 01 2004W.C. Rounds and G.-Q. Zhang (2001) have proposed to study a form of disjunctive logic programming generalized to algebraic domains. This system allows reasoning with information which is hierarchically structured and forms a (suitable) domain. We extend ... More
Shallow Circuits with High-Powered InputsApr 28 2010Jul 30 2010A polynomial identity testing algorithm must determine whether an input polynomial (given for instance by an arithmetic circuit) is identically equal to 0. In this paper, we show that a deterministic black-box identity testing algorithm for (high-degree) ... More
A hitting set construction, with application to arithmetic circuit lower boundsJul 31 2009Dec 08 2009A polynomial identity testing algorithm must determine whether a given input polynomial is identically equal to 0. We give a deterministic black-box identity testing algorithm for univariate polynomials of the form $\sum_{j=0}^t c_j X^{\alpha_j} (a + ... More
Simple Necessary Conditions for the Existence of a Hamiltonian Path with Applications to Cactus GraphsSep 05 2017We describe some necessary conditions for the existence of a Hamiltonian path in any graph (in other words, for a graph to be traceable). These conditions result in a linear time algorithm to decide the Hamiltonian path problem for cactus graphs. We apply ... More
A polynomial-time randomized reduction from tournament isomorphism to tournament asymmetryApr 27 2017The paper develops a new technique to extract a characteristic subset from a random source that repeatedly samples from a set of elements. Here a characteristic subset is a set that when containing an element contains all elements that have the same probability. ... More
The third law of thermodynamics or an absolute definition for Entropy. Part 1 : the origin and applications in thermodynamicsApr 26 2019May 29 2019This article describes the third law of thermodynamics. This law is often poorly known and is often decried, or even considered optional and irrelevant to describe weather and climate phenomena. This, however, is inaccurate and contrary to scientific ... More
Comment on the paper "Generalized dynamic equations related to condensation and freezing processes" by Wang and Huang (2018)Jan 25 2019Jan 28 2019The condensation Probability Function defined in papers of X.R. Wang is criticized on many aspects. The modified latent heat and potential temperature are plotted and compared to usual atmospheric formulations.
Two impurities in a Bose-Einstein condensate: from Yukawa to Efimov attracted polaronsJul 15 2016Apr 13 2018The well-known Yukawa and Efimov potentials are two different mediated interaction potentials. The first one arises in quantum field theory from the exchange of virtual particles. The second one is mediated by a real particle resonantly interacting with ... More
Doubled patterns are $3$-avoidableOct 06 2015In combinatorics on words, a word $w$ over an alphabet $\Sigma$ is said to avoid a pattern $p$ over an alphabet $\Delta$ if there is no factor $f$ of $w$ such that $f=h(p)$ where $h:\Delta^*\to\Sigma^*$ is a non-erasing morphism. A pattern $p$ is said ... More
Using the Incompressibility Method to obtain Local Lemma results for Ramsey-type ProblemsApr 04 2008We reveal a connection between the incompressibility method and the Lovasz local lemma in the context of Ramsey theory. We obtain bounds by repeatedly encoding objects of interest and thereby compressing strings. The method is demonstrated on the example ... More
A factorisation theorem for curve with vanishing self-intersectionMay 14 2014Jun 20 2014Let C be a curve in a compact Kahler surface Y. Assume that the self-intersection of C is vanishing, and the image of the fundamental group of C in Y is of infinite index in the fundamental group of Y. Does it follow that C is a fiber of a holomorphic ... More
On the Calderón-Zygmund lemma for Sobolev functionsOct 28 2008We correct an inaccuracy in the original proof
Géométrie, points entiers et courbes entièresSep 21 2007Let $X$ be a projective variety over a number field $K$ (resp. over $\mathbb{C}$). Let $H$ be the sum of ``sufficiently many positive divisors'' on $X$. We show that any set of quasi-integral points (resp. any integral curve) in $X-H$ is not Zariski dense. ... More
Géométrie des surfaces algébriques et points entiersJun 08 2006Let $X$ be a projective normal surface over a number field $K$. Let $H$ be the sum of four properly intersecting ample effective divisors on $X$. We show that any set of $S$-integral points in $X-H$ is not Zariski dense.
The $λ$-invariant measures of subcritical Bienaymé--Galton--Watson processesAug 04 2015Jun 13 2016A $\lambda$-invariant measure of a sub-Markov chain is a left eigenvector of its transition matrix of eigenvalue $\lambda$. In this article, we give an explicit integral representation of the $\lambda$-invariant measures of subcritical Bienaym\'e--Galton--Watson ... More
On Zero Divisors with Small Support in Group Rings of Torsion-Free GroupsFeb 29 2012Kaplanski's Zero Divisor Conjecture envisions that for a torsion-free group G and an integral domain R, the group ring R[G] does not contain non-trivial zero divisors. We define the length of an element a in R[G] as the minimal non-negative integer k ... More
Realistic interpretation of Grassmann variablesFeb 20 2012Mar 26 2015The goal of this paper is to define the Grassmann integral in terms of a limit of a sum around a well-defined contour so that Grassmann numbers gain geometric meaning rather than symbols. The unusual rescaling properties of the integration of an exponential ... More
Quantum mechanics and gravity as preclusion principles of four dimensional geometriesOct 01 2008Oct 16 2008The goal of this paper is to employ a "preclusion principle" originally suggested by Rafael Sorkin in order to come up with a relativistically covariant model of quantum mechanics and gravity. Space-time is viewed as geometry as opposed to dynamics, and ... More
A Geometrical Description of Spinor FieldsFeb 13 2008Aug 05 2008The goal of this paper is to present the way to define fermionic fields and their Lagrangians in terms of three orthogonal vector fields of norm 1 together with two real valued scalar fields. This paper is based on a toy model where there are no Grassmann ... More
Homogeneous solutions to the 3D Euler systemOct 12 2015We study stationary homogeneous solutions to the 3D Euler equation. The problem is motivated be recent exclusions of self-similar blowup for Euler and its relation to Onsager conjecture and intermittency. We reveal several new classes of solutions and ... More
Superluminality in dilatationally invariant generalized Galileon theoriesJul 31 2015Mar 25 2016We consider small perturbations about homogeneous backgrounds in dilatationally-invariant Galileon models. The issues we address are stability (absence of ghosts and gradient instabilities) and superluminality. We show that in Minkowski background, it ... More
Fast Estimators for Redshift-Space ClusteringJun 08 2015Jul 18 2015Redshift-space distortions in galaxy surveys happen along the radial direction, breaking statistical translation invariance. We construct estimators for radial distortions that, using only Fast Fourier Transforms (FFTs) of the overdensity field multipoles ... More
Phaseless inverse scattering in the one-dimensional caseMar 07 2015We consider the one-dimensional Schr\"odinger equation with a potential satisfying the standard assumptions of the inverse scattering theory and supported on the half-line $x\ge 0$. For this equation at fixed positive energy we give explicit formulas ... More
On transfinite nilpotence of the Vogel-Levine localizationJun 10 2014We construct a finitely-presented group such that its Vogel-Levine localization is not transfinitely nilpotent. This answers a problem of J. P. Levine.
Ensemble Copula Coupling as a Multivariate Discrete Copula ApproachMay 15 2013May 24 2013In probability and statistics, copulas play important roles theoretically as well as to address a wide range of problems in various application areas. In this paper, we introduce the concept of multivariate discrete copulas, discuss their equivalence ... More
Triangularizability of trace-class operators with increasing spectrumAug 31 2015Dec 08 2016For any measurable set $E$ of a measure space $(X, \mu)$, let $P_E$ be the (orthogonal) projection on the Hilbert space $L^2(X, \mu)$ with the range $ran \, P_E = \{f \in L^2(X, \mu) : f = 0 \ \ a.e. \ on \ E^c\}$ that is called a standard subspace of ... More
Ideal polyhedral surfaces in Fuchsian manifoldsApr 16 2018Apr 28 2019Let $S_{g,n}$ be a surface of genus $g > 1$ with $n>0$ punctures equipped with a complete hyperbolic cusp metric. Then it can be uniquely realized as the boundary metric of an ideal Fuchsian polyhedron. In the present paper we give a new variational proof ... More
Global existence and stability of nearly aligned flocksFeb 24 2018Mar 14 2018We study regularity of a hydrodynamic singular model of collective behavior introduced in \cite{ST1}. In this note we address the question of global well-posedness in multi-dimensional settings. It is shown that any initial data $(u,\rho)$ with small ... More
Factory of realities: on the emergence of virtual spatiotemporal structuresNov 30 2016The ubiquitous nature of modern Information Retrieval and Virtual World give rise to new realities. To what extent are these "realities" real? Which "physics" should be applied to quantitatively describe them? In this essay I dwell on few examples. The ... More
Autoparallel variational description of the free relativistic top third order dynamicsJul 12 2014A second order variational description of the autoparallel curves of some differential-geometric connection for the third order Mathisson's 'new mechanics' of a relativistic free spinning particle is suggested starting from general requirements of invariance ... More
Canonical formalism for quasi-classical particle "Zitterbewegung" in Ostrohrads'kyj mechanicsJul 15 2014The homogeneous canonical formalism of Rund is applied to the second-order Lagrangian model of the self-interacting particle of Bopp. The quasi-classical free spinning particle of Mathisson appears then as a constrained subsystem of the previous system. ... More
$\infty$-Open-multicommutativity in the category $\comp$Feb 23 2005In this paper the notion of $\infty$-open-multicommutativity of functors in the category of compact Hausdorff spaces is considered. This property is a generalization of the open-multicommutativity on the case of infinite diagrams. It is proved that every ... More
Frame expansions with erasures: an approach through the non-commutative operator theoryMay 28 2004In modern communication systems such as the Internet, random losses of information can be mitigated by oversampling the source. This is equivalent to expanding the source using overcomplete systems of vectors (frames), as opposed to the traditional basis ... More
Operator norm and numerical radius analogues of Cohen's inequalityMay 20 2019Let $D$ be an invertible multiplication operator on $L^2(X, \mu)$, and let $A$ be a bounded operator on $L^2(X, \mu)$. In this note we prove that $\|A\|^2 \le \|D A\| \, \|D^{-1} A\|$, where $\|\cdot\|$ denotes the operator norm. If, in addition, the ... More
Extended weight semigroups of affine spherical homogeneous spaces of non-simple semisimple algebraic groupsDec 01 2010Nov 13 2011The extended weight semigroup of a homogeneous space G/H of a connected semisimple algebraic group G characterizes the spectra of the representations of G on the spaces of regular sections of homogeneous linear bundles over G/H, including the space of ... More
Once More on Positive CommutatorsNov 05 2012Let A and B be bounded operators on a Banach lattice E such that the commutator C=AB-BA and the product BA are positive operators. If the product AB is a power-compact operator, then C is a quasi-nilpotent operator having a triangularizing chain of closed ... More
When powers of a matrix coincide with its Hadamard powersSep 01 2015We characterize matrices whose powers coincide with their Hadamard powers.
A study of energy concentration and drain in incompressible fluidsMay 07 2012May 22 2012In this paper we examine two opposite scenarios of energy behavior for solutions of the Euler equation. We show that if $u$ is a regular solution on a time interval $[0,T)$ and if $u \in L^rL^\infty$ for some $r\geq \frac{2}{N}+1$, where $N$ is the dimension ... More
Order problem for canonical systems and a conjecture of ValentFeb 16 2015We establish a sharp upper estimate for the order of a canonical system in terms of the Hamiltonian. This upper estimate becomes an equality in the case of Krein strings. As an application we prove a conjecture of Valent about the order of a certain class ... More
A generalization of Levinger's theorem to positive kernel operatorsApr 18 2003We prove some inequalities for the spectral radius of positive operators on Banach function spaces. In particular, we show the following extension of Levinger's theorem. Let $K$ be a positive compact kernel operator on $L^2(X,\mu)$ with the spectral radius ... More
Space-time discretization of the heat equation. A concise Matlab implementationDec 25 2012Sep 25 2013A concise Matlab implementation of a stable parallelizable space-time Petrov-Galerkin discretization for parabolic evolution equations is given. Emphasis is on reusability of spatial finite element codes.
Skipping Selected Steps of DWT Computation in Lossless JPEG 2000 for Improved BitratesAug 01 2016Jan 02 2017In order to improve bitrates of lossless JPEG 2000, we propose to modify the discrete wavelet transform (DWT) by skipping selected steps of its computation. We employ a heuristic to construct the skipped steps DWT (SS-DWT) in an image-adaptive way and ... More
Quasi-Hamiltonian description of classical spinNov 03 2015A family of Lagrange functions is considered, each producing the classical relativistic free spinning particle equation of motion of the third order. On this grounds a generalized Hamilton-Ostrohrads'kyj description of the free relativistic spherical ... More
The embedded contact homology of sutured solid toriOct 31 2009May 16 2011We calculate the relative versions of embedded contact homology, contact homology and cylindrical contact homology of the sutured solid torus $(S^1\times D^2,\Gamma)$, where $\Gamma$ consists of $2n$ parallel longitudinal sutures.
On the solutions of generalized discrete Poisson equationJun 19 2007The set of common numerical and analytical problems is introduced in the form of the generalized multidimensional discrete Poisson equation. It is shown that its solutions with square-summable discrete derivatives are unique up to a constant. The proof ... More
Invertibility of symmetric random matricesFeb 01 2011Mar 16 2012We study n by n symmetric random matrices H, possibly discrete, with iid above-diagonal entries. We show that H is singular with probability at most exp(-n^c), and the spectral norm of the inverse of H is O(sqrt{n}). Furthermore, the spectrum of H is ... More
On rational approximations of algebraic numbers of higher orders and certain parametrization for generalized Pell's equationsMar 29 2011A new algebraic object is introduced - recurrent fractions, which is an n-dimensional generalization of continued fractions. It is used to describe an algorithm for rational approximations of algebraic irrational numbers. Some parametrization for generalized ... More
A Model Structure On The Category Of Small Acyclic CategoriesAug 05 2015In this paper, we show that the Thomason model structure restricts to a Quillen equivalent cofibrantly generated model structure on the category of acyclic categories, whose generating cofibrations are the same as those generating the Thomason model structure. ... More
On Hardy-Littlewood-type and Hausdorff-Young-type inequalities for generalized Gegenbauer expansionsFeb 13 2016Using well-known techniques, we establish Hardy-Littlewood-type and Hausdorff-Young-type inequalities for generalized Gegenbauer expansions and their unification.
On Paley-type and Hausdorff-Young-Paley-type inequalities for generalized Gegenbauer expansionsFeb 26 2016We establish Paley-type and Hausdorff-Young-Paley-type inequalities for generalized Gegenbauer expansions.
Strongly solvable spherical subgroups and their combinatorial invariantsDec 13 2012Mar 26 2015A subgroup H of an algebraic group G is said to be strongly solvable if H is contained in a Borel subgroup of G. This paper is devoted to establishing relationships between the following three combinatorial classifications of strongly solvable spherical ... More
On the sharpness of one inequality of different metrics for algebraic polynomialsJul 05 2016We prove that the previously established inequality of different metrics for algebraic polynomials is sharp in the sense of order.