Search results for " property"

showing 10 items of 705 documents

Classical operators on weighted Banach spaces of entire functions

2013

We study the operators of differentiation and of integration and the Hardy operator on weighted Banach spaces of entire functions. We estimate the norm of the operators, study the spectrum, and analyze when they are surjective, power bounded, hypercyclic, and (uniformly) mean ergodic.

Unbounded operatorMathematics::Functional AnalysisPure mathematicsMathematical societyApproximation propertyApplied MathematicsGeneral MathematicsEntire functionBanach spaceFinite-rank operatorIntegration operatorOperator theoryWeighted Banach spacesHypecyclic operatorsDifferentiation operatorMean ergodic operatorsMATEMATICA APLICADAMathematicsVolume (compression)Proceedings of the American Mathematical Society
researchProduct

Spectra and essential spectral radii of composition operators on weighted Banach spaces of analytic functions

2008

AbstractWe determine the spectra of composition operators acting on weighted Banach spaces Hv∞ of analytic functions on the unit disc defined for a radial weight v, when the symbol of the operator has a fixed point in the open unit disc. We also investigate in this case the growth rate of the Koenigs eigenfunction and its relation with the essential spectral radius of the composition operator.

Unbounded operatorSpectral theoryComposition operatorApproximation propertySpectral radiusEssential spectral radiusApplied MathematicsMathematical analysisSpectrum (functional analysis)Composition operatorsFinite-rank operatorOperator theoryKoenigs eigenfunctionSpectrumAstrophysics::Earth and Planetary AstrophysicsAnalysisWeighted Bergman spaces of infinite orderMathematicsJournal of Mathematical Analysis and Applications
researchProduct

Operator martingale decomposition and the Radon-Nikodym property in Banach spaces

2010

Abstract We consider submartingales and uniform amarts of maps acting between a Banach lattice and a Banach lattice or a Banach space. In this measure-free setting of martingale theory, it is known that a Banach space Y has the Radon–Nikodým property if and only if every uniformly norm bounded martingale defined on the Chaney–Schaefer l-tensor product E ⊗ ˜ l Y , where E is a suitable Banach lattice, is norm convergent. We present applications of this result. Firstly, an analogues characterization for Banach lattices Y with the Radon–Nikodým property is given in terms of a suitable set of submartingales (supermartingales) on E ⊗ ˜ l Y . Secondly, we derive a Riesz decomposition for uniform …

Uniform amartPure mathematicsDinculeanu operatorApproximation propertyEberlein–Šmulian theoremBanach spaceRadon–Nikodým propertyFinite-rank operatorBanach manifoldBanach lattice Banach space Bochner norm Cone absolutely summing operator Convergent martingale Convergent submartingale Dinculeanu operator Radon–Nikodým propertySettore MAT/05 - Analisi MatematicaLp spaceC0-semigroupBanach lattice Banach space Bochner norm Cone absolutely summing operator Convergent martingale Convergent submartingale Dinculeanu operator Radon–Nikodým property Uniform amartMathematicsDiscrete mathematicsMathematics::Functional AnalysisBanach spaceApplied MathematicsConvergent martingaleConvergent submartingaleBanach latticeBochner normCone absolutely summing operatorBounded functionAnalysis
researchProduct

Resonant neumann equations with indefinite linear part

2015

We consider aseminonlinear Neumann problem driven by the $p$-Laplacian plus an indefinite and unbounded potential. The reaction of the problem is resonant at $\pm \infty$ with respect to the higher parts of the spectrum. Using critical point theory, truncation and perturbation techniques, Morse theory and the reduction method, we prove two multiplicity theorems. One produces three nontrivial smooth solutions and the second four nontrivial smooth solutions.

Unique continuation propertyReduction methodApplied MathematicsMathematical analysisMultiple solutionPerturbation (astronomy)AnalysiMultiplicity (mathematics)Neumann boundary conditionResonant equationAnalysisCritical groupMathematicsMorse theory
researchProduct

Weak chord-arc curves and double-dome quasisymmetric spheres

2014

Let $\Omega$ be a planar Jordan domain and $\alpha>0$. We consider double-dome-like surfaces $\Sigma(\Omega,t^{\alpha})$ over $\overline{\Omega}$ where the height of the surface over any point $x\in\overline{\Omega}$ equals $\text{dist}(x,\partial\Omega)^{\alpha}$. We identify the necessary and sufficient conditions in terms of $\Omega$ and $\alpha$ so that these surfaces are quasisymmetric to $\mathbb{S}^2$ and we show that $\Sigma(\Omega,t^{\alpha})$ is quasisymmetric to the unit sphere $\mathbb{S}^2$ if and only if it is linearly locally connected and Ahlfors $2$-regular.

Unit sphereChord (geometry)QA299.6-43330C65 30C62Mathematics::Complex VariablesApplied Mathematics010102 general mathematicsdouble-dome-like surfacesMetric Geometry (math.MG)16. Peace & justice01 natural sciencesOmegachord-arc propertyCombinatoricsMathematics - Metric GeometryFOS: Mathematicsquasisymmetric spheresAhlfors 2-regularityMathematics::Metric GeometrySPHERESGeometry and Topology0101 mathematicsahlfors 2-regularityAnalysisMathematics
researchProduct

Strongly extreme points and approximation properties

2017

We show that if $x$ is a strongly extreme point of a bounded closed convex subset of a Banach space and the identity has a geometrically and topologically good enough local approximation at $x$, then $x$ is already a denting point. It turns out that such an approximation of the identity exists at any strongly extreme point of the unit ball of a Banach space with the unconditional compact approximation property. We also prove that every Banach space with a Schauder basis can be equivalently renormed to satisfy the sufficient conditions mentioned. In contrast to the above results we also construct a non-symmetric norm on $c_0$ for which all points on the unit sphere are strongly extreme, but …

Unit spherePure mathematicsMathematics::Functional AnalysisApproximation propertyGeneral MathematicsBanach spaceRegular polygonSchauder basisFunctional Analysis (math.FA)Mathematics - Functional Analysis46B20Bounded functionFOS: MathematicsPoint (geometry)Extreme pointMathematics
researchProduct

On holomorphic functions attaining their norms

2004

Abstract We show that on a complex Banach space X , the functions uniformly continuous on the closed unit ball and holomorphic on the open unit ball that attain their norms are dense provided that X has the Radon–Nikodym property. We also show that the same result holds for Banach spaces having a strengthened version of the approximation property but considering just functions which are also weakly uniformly continuous on the unit ball. We prove that there exists a polynomial such that for any fixed positive integer k , it cannot be approximated by norm attaining polynomials with degree less than k . For X=d ∗ (ω,1) , a predual of a Lorentz sequence space, we prove that the product of two p…

Unit spherePure mathematicsMathematics::Functional AnalysisLorentz sequence spaceFunction spaceApproximation propertyApplied MathematicsMathematical analysisBanach spaceHolomorphic functionNorm attainingHolomorphic functionPolynomialUniform continuityNorm (mathematics)Ball (mathematics)AnalysisMathematicsJournal of Mathematical Analysis and Applications
researchProduct

Perceived problems with collateral: The value of informal networking

2020

Abstract Many businesses in emerging economies are financially constrained due to their limited use of formal loans. Recent evidence suggests that negative perceptions discourage entrepreneurs from applying for loans. One of the main issues entrepreneurs mention is unattainable collateral requirements. In this paper, we contribute to this line of research by investigating the effect of networking with fellow entrepreneurs on perceived collateral problems. Drawing on quantitative and qualitative data originating from female entrepreneurs in Tanzania, we find that through networking, entrepreneurs are exposed to stories of their peers’ experiences with loans which influence their perceptions …

Value (ethics)Economics and EconometricsCollateralPerceptionmedia_common.quotation_subjectFemale entrepreneursAccess to financeQualitative propertyBusinessMarketingEmerging marketsFinancemedia_commonInternational Review of Economics & Finance
researchProduct

Patterns of Transnational Urban Drift to Latvia

2021

This chapter extends the previous knowledge on the effects of migrants’ transnational lifestyle by studying residential patterns and life preferences of Latvian return migrants and arriving foreigners. We aim to explore the geographies and narratives from interviews with migrants who had shifted to more dynamic and prosperous urban/suburban locations. The contribution sends forward the interplay between immigration and return migration experiences by questioning: (1) What are the migratory flows’ geographical contexts? (2) How do they overlap and illuminate the process of ‘urban drift’? (3) How do the ‘urban drifters’ value their current life preferences and migratory experiences? Using sec…

Value (ethics)Geographymedia_common.quotation_subjectImmigrationlanguageLatvianQualitative propertyNarrativeEconomic geographylanguage.human_languagemedia_common
researchProduct

Co‐parenting through subsidiaries: A model of value creation in the multinational firm

2017

Research summary We analyze a novel way to configure and manage multinational networks and propose a model of "co-parenting", characterized by the sharing of parenting roles and distribution of responsibilities between two units. We develop our argument around the notion of the springboard subsidiary, an operating subsidiary which assumes headquarters’ functions since it shares greater institutional closeness with both the headquarters’ country as well as with the host region. Based upon qualitative data, our inductive model revolves around three stages: establishment, consolidation and maturity, each of which reflects distinct roles and loci of decision making among the three actors involv…

Value creationStrategy and Management05 social sciencesSubsidiaryClosenessQualitative propertyConsolidation (business)Multinational corporationParenting roles0502 economics and business050211 marketingBusinessBusiness and International ManagementMarketing050203 business & managementBusiness tiesIndustrial organizationGlobal Strategy Journal
researchProduct