Search results for "metric space"

showing 10 items of 316 documents

On a theorem of Khan in a generalized metric space

2013

Existence and uniqueness of fixed points are established for a mapping satisfying a contractive condition involving a rational expression on a generalized metric space. Several particular cases and applications as well as some illustrative examples are given.

Discrete mathematicsArticle Subjectlcsh:MathematicsInjective metric spacerational expression.Pseudometric spaceFixed pointFixed pointlcsh:QA1-939Convex metric spaceMetric spaceSettore MAT/05 - Analisi MatematicaMetric (mathematics)Uniquenessgeneralized metric spaceMetric differentialMathematics
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Capabilities of Ultrametric Automata with One, Two, and Three States

2016

Ultrametric automata use p-adic numbers to describe the random branching of the process of computation. Previous research has shown that ultrametric automata can have a significant decrease in computing complexity. In this paper we consider the languages that can be recognized by one-way ultrametric automata with one, two, and three states. We also show an example of a promise problem that can be solved by ultrametric integral automaton with three states.

Discrete mathematicsBinary treeComputationPrime number020206 networking & telecommunications02 engineering and technologyNonlinear Sciences::Cellular Automata and Lattice GasesCondensed Matter::Disordered Systems and Neural NetworksAutomatonTuring machinesymbols.namesakeRegular language0202 electrical engineering electronic engineering information engineeringsymbolsMathematics::Metric Geometry020201 artificial intelligence & image processingPromise problemUltrametric spaceComputer Science::DatabasesComputer Science::Formal Languages and Automata TheoryMathematics
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Fixed points for multivalued mappings in b-metric spaces

2015

In 2012, Samet et al. introduced the notion ofα-ψ-contractive mapping and gave sufficient conditions for the existence of fixed points for this class of mappings. The purpose of our paper is to study the existence of fixed points for multivalued mappings, under anα-ψ-contractive condition of Ćirić type, in the setting of completeb-metric spaces. An application to integral equation is given.

Discrete mathematicsClass (set theory)Article Subjectlcsh:MathematicsApplied Mathematicsalpha-admissible multivalued mapping b-metric space fixed point integral equation.Fixed pointType (model theory)lcsh:QA1-939Integral equationMetric spaceSettore MAT/03 - GeometriaAnalysisMathematics
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Fixed Points for Weakα-ψ-Contractions in Partial Metric Spaces

2013

Recently, Samet et al. (2012) introduced the notion ofα-ψ-contractive mappings and established some fixed point results in the setting of complete metric spaces. In this paper, we introduce the notion of weakα-ψ-contractive mappings and give fixed point results for this class of mappings in the setting of partial metric spaces. Also, we deduce fixed point results in ordered partial metric spaces. Our results extend and generalize the results of Samet et al.

Discrete mathematicsClass (set theory)Metric spacePure mathematicsApplied MathematicsInjective metric spaceMetric mapProduct metricFixed pointAnalysisMathematicsIntrinsic metricConvex metric spaceAbstract and Applied Analysis
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On the Hierarchy Classes of Finite Ultrametric Automata

2015

This paper explores the language classes that arise with respect to the head count of a finite ultrametric automaton. First we prove that in the one-way setting there is a language that can be recognized by a one-head ultrametric finite automaton and cannot be recognized by any k-head non-deterministic finite automaton. Then we prove that in the two-way setting the class of languages recognized by ultrametric finite k-head automata is a proper subclass of the class of languages recognized by (k + 1)-head automata. Ultrametric finite automata are similar to probabilistic and quantum automata and have only just recently been introduced by Freivalds. We introduce ultrametric Turing machines an…

Discrete mathematicsClass (set theory)TheoryofComputation_COMPUTATIONBYABSTRACTDEVICESFinite-state machineHierarchy (mathematics)Nonlinear Sciences::Cellular Automata and Lattice GasesCondensed Matter::Disordered Systems and Neural NetworksAutomatonAlgebraTuring machinesymbols.namesakeTheoryofComputation_MATHEMATICALLOGICANDFORMALLANGUAGESsymbolsMathematics::Metric GeometryQuantum finite automataAutomata theoryUltrametric spaceComputer Science::Formal Languages and Automata TheoryMathematicsofComputing_DISCRETEMATHEMATICSMathematics
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Vector-valued meromorphic functions

2002

A locally complete locally convex space E satisfies that every weakly meromorphic function defined on an open subset of \( \mathbb{C} \) with values in E is meromorphic if and only if E does not contain a countable product of copies of \( \mathbb{C} \). A characterization of locally complete spaces in the spirit of known characterizations of the (metric) convex compactness property is also given.

Discrete mathematicsCompact spaceGeneral MathematicsProduct (mathematics)Regular polygonConvex setCountable setCharacterization (mathematics)Complete metric spaceMeromorphic functionMathematics
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On generalized weakly G-contraction mapping in G-metric spaces

2011

In this paper, we establish some common fixed point results for two self-mappings f and g on a generalized metric space X. To prove our results we assume that f is a generalized weakly G-contraction mapping of types A and B with respect to g.

Discrete mathematicsComputational MathematicsMetric spaceComputational Theory and MathematicsModeling and SimulationInjective metric spaceMetric (mathematics)Metric mapProduct metricContraction mappingIntrinsic metricMathematicsConvex metric spaceComputers & Mathematics with Applications
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Common fixed points in generalized metric spaces

2012

Abstract We establish some common fixed point theorems for mappings satisfying a ( ψ , φ ) -weakly contractive condition in generalized metric spaces. Presented theorems extend and generalize many existing results in the literature.

Discrete mathematicsComputational MathematicsMetric spaceFixed-point iterationSettore MAT/05 - Analisi MatematicaApplied MathematicsGeneralized metric weakly contractive condition contraction of integral type fixed point common fixed points.Common fixed pointProduct metricFixed pointIntrinsic metricMathematicsConvex metric space
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The branch set of a quasiregular mapping between metric manifolds

2016

Abstract In this note, we announce some new results on quantitative countable porosity of the branch set of a quasiregular mapping in very general metric spaces. As applications, we solve a recent conjecture of Fassler et al., an open problem of Heinonen–Rickman, and an open question of Heinonen–Semmes.

Discrete mathematicsConjectureMathematics::Complex VariablesOpen problem010102 general mathematicsMathematical analysisGeneral Medicine01 natural sciences010101 applied mathematicsSet (abstract data type)Metric spaceMetric (mathematics)Mathematics::Metric GeometryCountable set0101 mathematicsMathematicsComptes Rendus Mathematique
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Coupled fixed point, F-invariant set and fixed point of N-order

2010

‎In this paper‎, ‎we establish some new coupled fixed point theorems in complete metric spaces‎, ‎using a new concept of $F$-invariant set‎. ‎We introduce the notion of fixed point of $N$-order as natural extension of that of coupled fixed point‎. ‎As applications‎, ‎we discuss and adapt the presented results to the setting of partially ordered cone metric spaces‎. ‎The presented results extend and complement some known existence results from the literature‎.

Discrete mathematicsCoupled fixed point F-invariant set fixed point of N-order partially ordered set cone metric spaceControl and OptimizationAlgebra and Number Theory47H10‎Fixed-point theoremFixed pointFixed-point propertyCoupled fixed point‎partially ordered setLeast fixed point‎$F$-invariant set54H25Schauder fixed point theoremFixed-point iterationSettore MAT/05 - Analisi Matematica‎34B15‎cone metric space‎fixed point of $N$-orderKakutani fixed-point theoremAnalysisHyperbolic equilibrium pointMathematics
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