Search results for " function"

showing 10 items of 9395 documents

Strict u-ideals in Banach spaces

2009

We study strict u-ideals in Banach spaces. A Banach space X is a strict u-ideal in its bidual when the canonical decomposition X = X X ? is unconditional. We characterize Banach spaces which are strict u-ideals in their bidual and show that if X is a strict u-ideal in a Banach space Y then X contains c0. We also show that '1 is not a u-ideal.

Discrete mathematicsMathematics::Functional AnalysisMathematics::Commutative AlgebraApproximation propertyGeneral MathematicsEberlein–Šmulian theoremInfinite-dimensional vector functionBanach spaceInterpolation spaceBanach manifoldC0-semigroupLp spaceMathematicsStudia Mathematica
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Entire Functions of Bounded Type on Fréchet Spaces

1993

We show that holomorphic mappings of bounded type defined on Frechet spaces extend to the bidual. The relationship between holomorphic mappings of bounded type and of uniformly bounded type is discussed and some algebraic and topological properties of the space of all entire mappings of (uniformly) bounded type are proved, for example a holomorphic version of Schauder's theorem.

Discrete mathematicsMathematics::Functional AnalysisMathematics::Complex VariablesGeneral MathematicsBounded functionUniform boundednessBounded deformationInfinite-dimensional holomorphyBounded inverse theoremIdentity theoremExponential typeBounded operatorMathematicsMathematische Nachrichten
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Radon–Nikodym Property and Area Formula for Banach Homogeneous Group Targets

2013

We prove a Rademacher-type theorem for Lipschitz mappings from a subset of a Carnot group to a Banach homogeneous group, equipped with a suitably weakened Radon-Nikodym property. We provide a metric area formula that applies to these mappings and more generally to all almost everywhere metrically differentiable Lipschitz mappings defined on a Carnot group. peerReviewed

Discrete mathematicsMathematics::Functional AnalysisProperty (philosophy)General Mathematicsmetric area formulata111Mathematics::Analysis of PDEsCarnot groupBanach homogeneous groupsalmost everywhere differentiabilityRadon-Nikodym propertyLipschitz continuityRadon–Nikodym theoremBanach homogeneous groups; metric area formula; almost everywhere differentiability; Radon-Nikodym propertyMetric (mathematics)Homogeneous groupMathematics::Metric GeometryAlmost everywhereDifferentiable functionMathematics
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Henstock–Kurzweil–Pettis integrability of compact valued multifunctions with values in an arbitrary Banach space

2013

Abstract The aim of this paper is to describe Henstock–Kurzweil–Pettis (HKP) integrable compact valued multifunctions. Such characterizations are known in case of functions (see Di Piazza and Musial (2006)  [16] ). It is also known (see Di Piazza and Musial (2010)  [19] ) that each HKP-integrable compact valued multifunction can be represented as a sum of a Pettis integrable multifunction and of an HKP-integrable function. Invoking to that decomposition, we present a pure topological characterization of integrability. Having applied the above results, we obtain two convergence theorems, that generalize results known for HKP-integrable functions. We emphasize also the special role played in …

Discrete mathematicsMathematics::Functional AnalysisProperty (philosophy)Henstock integralIntegrable systemApplied MathematicsBanach spaceconvergence theoremsFunction (mathematics)Characterization (mathematics)set-valued Henstock-Kurzweil-Pettis integralset-valued Pettis integralsupport functionMultifunctionSettore MAT/05 - Analisi MatematicaConvergence (routing)AnalysisselectorMathematicsJournal of Mathematical Analysis and Applications
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Fixed point properties and proximinality in Banach spaces

2009

Abstract In this paper we prove the existence of a fixed point for several classes of mappings (mappings admitting a center, nonexpansive mappings, asymptotically nonexpansive mappings) defined on the closed convex subsets of a Banach space satisfying some proximinality conditions. In particular, we derive a sufficient condition, more general than weak star compactness, such that if C is a bounded closed convex subset of l 1 satisfying this condition, then every nonexpansive mapping T : C → C has a fixed point.

Discrete mathematicsMathematics::Functional AnalysisPure mathematicsApplied MathematicsRegular polygonBanach spaceCenter (group theory)Star (graph theory)Fixed pointCompact spaceBounded functionCoincidence pointAnalysisMathematicsNonlinear Analysis: Theory, Methods & Applications
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A note on banach partial *-algebras

2006

A Banach partial *-algebra is a locally convex partial *-algebra whose total space is a Banach space. A Banach partial *-algebra is said to be of type (B) if it possesses a generating family of multiplier spaces that are also Banach spaces. We describe the basic properties of such objects and display a number of examples, namely LP-like function spaces and spaces of operators on Hilbert scales.

Discrete mathematicsMathematics::Functional AnalysisPure mathematicsApproximation propertyGeneral MathematicsInfinite-dimensional vector functionEberlein–Šmulian theoremBanach spaceInterpolation spaceFinite-rank operatorBanach manifoldLp spaceMathematicsMediterranean Journal of Mathematics
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A Riemann manifold structure of the spectra of weighted algebras of holomorphic functions

2009

[EN] In this paper we give general conditions on a countable family V of weights on an unbounded open set U in a complex Banach space X such that the weighted space HV (U) of holomorphic functions on U has a Frechet algebra structure. For such weights it is shown that the spectrum of HV(U) has a natural analytic manifold structure when X is a symmetrically regular Banach space, and in particular when X = C-n. (C) 2009 Elsevier Ltd. All rights reserved.

Discrete mathematicsMathematics::Functional AnalysisPure mathematicsFréchet algebraWeighted space of holomorphic functionsHolomorphic functional calculusInfinite-dimensional vector functionSpectrum (functional analysis)Holomorphic functionFrechet algebraBanach manifoldAnalytic manifold structureAnalytic manifoldBergman spaceSymmetrically regular Banach spaceGeometry and TopologyMATEMATICA APLICADAWeighted spaceMathematicsTopology
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A space of projections on the Bergman space

2010

We define a set of projections on the Bergman space A 2 , which is parameterized by an ane subset of a Banach space of holomorphic functions in the disk and which includes the classical Forelli-Rudin projections.

Discrete mathematicsMathematics::Functional AnalysisPure mathematicsMathematics::Complex VariablesGeneral MathematicsInfinite-dimensional vector functionHolomorphic functionBanach spaceMathematics::General TopologyQuotient space (linear algebra)Continuous functions on a compact Hausdorff spaceBergman spaceBesov spaceBergman kernelMathematicsAnnales Academiae Scientiarum Fennicae Mathematica
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Remarks on mapping properties for the Bargmann transform on modulation spaces

2011

We investigate the mapping properties for the Bargmann transform and prove that this transform is isometricand bijective from modulation spaces to convenient Banach spaces of analytic functions.

Discrete mathematicsMathematics::Functional AnalysisPure mathematicsModulation spaceFunctional analysisApplied MathematicsBanach spaceBijectionInterpolation spaceLp spaceAnalysisHarmonic oscillatorAnalytic functionMathematicsIntegral Transforms and Special Functions
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Fredholm composition operators on algebras of analytic functions on Banach spaces

2010

AbstractWe prove that Fredholm composition operators acting on the uniform algebra H∞(BE) of bounded analytic functions on the open unit ball of a complex Banach space E with the approximation property are invertible and arise from analytic automorphisms of the ball.

Discrete mathematicsMathematics::Functional AnalysisPure mathematicsSpectral theoryApproximation propertyFredholm operatorGlobal analytic functionFinite-rank operatorFredholm integral equationFredholm operatorCompact operatorFredholm theorysymbols.namesakesymbolsComposition operatorBounded analytic functionAnalysisMathematicsJournal of Functional Analysis
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