Search results for "Variable"

showing 10 items of 1674 documents

Large-x Analysis of an Operator-Valued Riemann–Hilbert Problem

2015

International audience; The purpose of this paper is to push forward the theory of operator-valued Riemann-Hilbert problems and demonstrate their effectiveness in respect to the implementation of a non-linear steepest descent method a la Deift-Zhou. In this paper, we demonstrate that the operator-valued Riemann-Hilbert problem arising in the characterization of so-called c-shifted integrable integral operators allows one to extract the large-x asymptotics of the Fredholm determinant associated with such operators.

Pure mathematicsIntegrable systemNonlinear schrodinger-equationMathematics::Complex VariablesGeneral Mathematics010102 general mathematicsMathematicsofComputing_NUMERICALANALYSIS[ MATH.MATH-MP ] Mathematics [math]/Mathematical Physics [math-ph]Fredholm determinantImpenetrable bose-gas[ MATH.MATH-FA ] Mathematics [math]/Functional Analysis [math.FA][MATH.MATH-FA]Mathematics [math]/Functional Analysis [math.FA]01 natural sciencessymbols.namesakeRiemann hypothesisOperator (computer programming)[MATH.MATH-MP]Mathematics [math]/Mathematical Physics [math-ph]0103 physical sciencesHilbert's problemssymbolsMethod of steepest descentRiemann–Hilbert problem010307 mathematical physics0101 mathematicsMathematics
researchProduct

Sharpness of uniform continuity of quasiconformal mappings onto s-John domains

2017

We construct examples to show the sharpness of uniform continuity of quasiconformal mappings onto $s$-John domains. Our examples also give a negative answer to a prediction in [7].

Pure mathematicsMathematics - Complex VariablesGeneral Mathematics010102 general mathematicsta111s-John domainquasiconformal mappinginternal diameter16. Peace & justice01 natural sciencesNegative - answerUniform continuity30C62 30C65FOS: Mathematics0101 mathematicsinternal metricComplex Variables (math.CV)Construct (philosophy)Mathematicsuniform continuity
researchProduct

Sharp estimate on the inner distance in planar domains

2020

We show that the inner distance inside a bounded planar domain is at most the one-dimensional Hausdorff measure of the boundary of the domain. We prove this sharp result by establishing an improved Painlev\'e length estimate for connected sets and by using the metric removability of totally disconnected sets, proven by Kalmykov, Kovalev, and Rajala. We also give a totally disconnected example showing that for general sets the Painlev\'e length bound $\kappa(E) \le\pi \mathcal{H}^1(E)$ is sharp.

Pure mathematicsMathematics - Complex VariablesGeneral MathematicsBoundary (topology)accessible pointsMetric Geometry (math.MG)31A15Domain (mathematical analysis)inner distancePlanarMathematics - Metric GeometryPrimary 28A75. Secondary 31A15Bounded functionTotally disconnected spaceMetric (mathematics)FOS: Mathematics28A75Hausdorff measureComplex Variables (math.CV)Painlevé lengthMathematics
researchProduct

Quasisymmetric Koebe uniformization with weak metric doubling measures

2020

We give a characterization of metric spaces quasisymmetrically equivalent to a finitely connected circle domain. This result generalizes the uniformization of Ahlfors 2-regular spaces by Merenkov and Wildrick. peerReviewed

Pure mathematicsMathematics - Complex VariablesMathematics::Complex VariablesGeneral MathematicsCharacterization (mathematics)metriset avaruudetDomain (mathematical analysis)funktioteoriaMetric spaceMetric (mathematics)FOS: MathematicsMathematics::Metric GeometrymittateoriaComplex Variables (math.CV)Uniformization (set theory)MathematicsIllinois Journal of Mathematics
researchProduct

Dirichlet approximation and universal Dirichlet series

2016

We characterize the uniform limits of Dirichlet polynomials on a right half plane. In the Dirichlet setting, we find approximation results, with respect to the Euclidean distance and {to} the chordal one as well, analogous to classical results of Runge, Mergelyan and Vitushkin. We also strengthen the notion of universal Dirichlet series.

Pure mathematicsMathematics - Complex VariablesUniversal seriesApplied MathematicsGeneral Mathematics010102 general mathematicsMathematics::Analysis of PDEsMathematics::Spectral Theory16. Peace & justice01 natural sciencesDirichlet distributionEuclidean distancesymbols.namesakeChordal graph0103 physical sciencesRight half-planeFOS: Mathematics30K10symbols010307 mathematical physicsComplex Variables (math.CV)0101 mathematicsDirichlet seriesMathematicsProceedings of the American Mathematical Society
researchProduct

Classification of Stable Germs by Their Local Algebras

2020

We prove Mather’s theorem that stable germs are classified up to \(\mathscr {A}\)-equivalence by their local algebras. We sketch his calculation of the nice dimensions, together with his classification of stable germs in the nice dimensions, and prove that in the nice dimensions every stable germ is quasi-homogeneous with respect to suitable coordinates.

Pure mathematicsMathematics::Algebraic GeometryMathematics::Complex VariablesGermSketchMathematics
researchProduct

Holomorphic mappings of bounded type

1992

Abstract For a Banach space E, we prove that the Frechet space H b(E) is the strong dual of an (LB)-space, B b(E), which leads to a linearization of the holomorphic mappings of bounded type. It is also shown that the holomorphic functions defined on (DFC)-spaces are of uniformly bounded type.

Pure mathematicsMathematics::Complex VariablesApplied MathematicsHolomorphic functional calculusMathematical analysisHolomorphic functionBanach spaceType (model theory)Bounded typeLinearizationFréchet spaceUniform boundednessAnalysisMathematicsJournal of Mathematical Analysis and Applications
researchProduct

Königs eigenfunction for composition operators on Bloch and H∞ type spaces

2017

Abstract We discuss when the Konigs eigenfunction associated with a non-automorphic selfmap of the complex unit disc that fixes the origin belongs to Banach spaces of holomorphic functions of Bloch and H ∞ type. In the latter case, our characterization answers a question of P. Bourdon. Some spectral properties of composition operators on H ∞ for unbounded Konigs eigenfunction are obtained.

Pure mathematicsMathematics::Complex VariablesComposition operatorApplied Mathematics010102 general mathematicsMathematical analysisBanach spaceHolomorphic functionComposition (combinatorics)EigenfunctionType (model theory)Characterization (mathematics)01 natural sciences010101 applied mathematicsComputer Science::Discrete Mathematics0101 mathematicsUnit (ring theory)AnalysisMathematicsJournal of Mathematical Analysis and Applications
researchProduct

Fractional integration, differentiation, and weighted Bergman spaces

1999

We study the action of fractional differentiation and integration on weighted Bergman spaces and also the Taylor coeffficients of functions in certain subclasses of these spaces. We then derive several criteria for the multipliers between such spaces, complementing and extending various recent results. Univalent Bergman functions are also considered.

Pure mathematicsMathematics::Complex VariablesGeneral Mathematics010102 general mathematicsMathematical analysisMathematical statisticsTaylor coefficientsMathematics & Statistics01 natural sciencesAction (physics)010101 applied mathematicsFractional differentiationBergman space0101 mathematicsMathematicsBergman kernel
researchProduct

Infinite Dimensional Holomorphy

2019

We give an introduction to vector-valued holomorphic functions in Banach spaces, defined through Frechet differentiability. Every function defined on a Reinhardt domain of a finite-dimensional Banach space is analytic, i.e. can be represented by a monomial series expansion, where the family of coefficients is given through a Cauchy integral formula. Every separate holomorphic (holomorphic on each variable) function is holomorphic. This is Hartogs’ theorem, which is proved using Leja’s polynomial lemma. For infinite-dimensional spaces, homogeneous polynomials are defined as the diagonal of multilinear mappings. A function is holomorphic if and only if it is Gâteaux holomorphic and continuous…

Pure mathematicsMathematics::Complex VariablesHomogeneous polynomialBanach spaceHolomorphic functionDifferentiable functionHartogs' theoremInfinite-dimensional holomorphyMathematics::Symplectic GeometryCauchy's integral formulaAnalytic functionMathematics
researchProduct