Search results for "Metric space"

showing 6 items of 316 documents

On multivalued weakly Picard operators in partial Hausdorff metric spaces

2015

We discuss multivalued weakly Picard operators on partial Hausdorff metric spaces. First, we obtain Kikkawa-Suzuki type fixed point theorems for a new type of generalized contractive conditions. Then, we prove data dependence of a fixed points set theorem. Finally, we present sufficient conditions for well-posedness of a fixed point problem. Our results generalize, complement and extend classical theorems in metric and partial metric spaces.

multivalued operatorDiscrete mathematicsApplied MathematicsInjective metric spacedata dependencepartial metric spaceFixed-point theoremEquivalence of metricsConvex metric spaceIntrinsic metricMetric spaceHausdorff distancefixed pointSettore MAT/05 - Analisi MatematicaMetric (mathematics)Geometry and TopologyMathematicsFixed Point Theory and Applications
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The Hajłasz Capacity Density Condition is Self-improving

2022

We prove a self-improvement property of a capacity density condition for a nonlocal Hajlasz gradient in complete geodesic spaces with a doubling measure. The proof relates the capacity density condition with boundary Poincare inequalities, adapts Keith-Zhong techniques for establishing local Hardy inequalities and applies Koskela-Zhong arguments for proving self-improvement properties of local Hardy inequalities. This leads to a characterization of the Hajlasz capacity density condition in terms of a strict upper bound on the upper Assouad codimension of the underlying set, which shows the self-improvement property of the Hajlasz capacity density condition. Open Access funding provided than…

osittaisdifferentiaaliyhtälötHajlasz gradientHajłasz gradientpotentiaaliteoriaanalysis on metric spacescapacity density conditionGeometry and Topologyharmoninen analyysiepäyhtälötmetriset avaruudetThe Journal of Geometric Analysis
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Multi-marginal entropy-transport with repulsive cost

2020

In this paper we study theoretical properties of the entropy-transport functional with repulsive cost functions. We provide sufficient conditions for the existence of a minimizer in a class of metric spaces and prove the $\Gamma$-convergence of the entropy-transport functional to a multi-marginal optimal transport problem with a repulsive cost. We also prove the entropy-regularized version of the Kantorovich duality.

osittaisdifferentiaaliyhtälötPure mathematicsApplied Mathematics010102 general mathematicsMathematicsofComputing_NUMERICALANALYSISA domainFOS: Physical sciencesMathematical Physics (math-ph)matemaattinen optimointi01 natural sciences010101 applied mathematicsMetric spaceMathematics - Analysis of PDEsOptimization and Control (math.OC)FOS: MathematicsEntropy (information theory)0101 mathematicsMathematics - Optimization and ControlMathematical PhysicsAnalysisAnalysis of PDEs (math.AP)MathematicsCalculus of Variations and Partial Differential Equations
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Monotone generalized nonlinear contractions and fixed point theorems in ordered metric spaces

2011

The purpose of this paper is to present some fixed point theorems for T -weakly isotone increasing mappings which satisfy a generalized nonlinear contractive condition in complete ordered metric spaces. As application, we establish an existence theorem for a solution of some integral equations.

partially ordered setPure mathematicsweakly contractive conditionExistence theoremFixed-point theoremFixed pointFixed pointFixed-point propertyComplete metric spaceComputer Science ApplicationsCombinatoricsMetric spaceSettore MAT/05 - Analisi Matematicacomplete metric spaceModelling and SimulationModeling and Simulationaltering distance functionPartially ordered setCoincidence pointMathematicsMathematical and Computer Modelling
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Topics in calculus and geometry on metric spaces

2022

In this thesis we present an overview of some important known facts related to topology, geometry and calculus on metric spaces. We discuss the well known problem of the existence of a lipschitz equivalent metric to a given quasiultrametric, revisiting known results and counterexamples and providing some new theorems, in an unified approach. Also, in the general setting of a quasi-metric doubling space, suitable partition of unity lemmas allows us to obtain, in step two Carnot groups, the well known Whitney’s extension theorem for a given real function of class C^m defined on a closed subset of the whole space: this result relies on relevant properties of the symmetrized Taylor’s polynomial…

quasi-ultrametric spacecalculuCarnot groupconvexityLipschitz functionmetric spaceWhitney type extension theoremextension theoremdoubling spacepartitionSettore MAT/05 - Analisi Matematicasemi-distance distancepaces of homogeneous typequasi-metric spacesmetrization theoremof unity lemma
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Some fixed point theorems for occasionally weakly compatible mappings in probabilistic semi-metric spaces

2009

We prove some common fixed point theorems in probabilistic semi-metric spaces for occasionally weakly compatible mappings satisfying a generalized contractive condition. We give also results of common fixed point for mappings satisfying a condition of integral type.

semi-metric spacesSettore MAT/05 - Analisi MatematicaOccasionally weakly compatible mappingcommon fixed point theorem
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