Search results for "c space"

showing 10 items of 552 documents

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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On a Conjecture by Christian Choffrut

2017

It is one of the most famous open problems to determine the minimum amount of states required by a deterministic finite automaton to distinguish a pair of strings, which was stated by Christian Choffrut more than thirty years ago. We investigate the same question for different automata models and we obtain new upper and lower bounds for some of them including alternating, ultrametric, quantum, and affine finite automata.

Discrete mathematicsFinite-state machineConjecture010102 general mathematics02 engineering and technology01 natural sciencesUpper and lower boundsAutomatonDeterministic finite automatonCounting problem0202 electrical engineering electronic engineering information engineeringComputer Science (miscellaneous)020201 artificial intelligence & image processingAffine transformation0101 mathematicsUltrametric spaceMathematicsInternational Journal of Foundations of Computer Science
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Counting with Probabilistic and Ultrametric Finite Automata

2014

We investigate the state complexity of probabilistic and ultrametric finite automata for the problem of counting, i.e. recognizing the one-word unary language \(C_n=\left\{ 1^n \right\} \). We also review the known results for other types of automata.

Discrete mathematicsFinite-state machineState complexityUnary languageProbabilistic logicQuantum finite automataNonlinear Sciences::Cellular Automata and Lattice GasesUltrametric spaceComputer Science::Formal Languages and Automata TheoryMathematicsAutomaton
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Common fixed points for discontinuous mappings in fuzzy metric spaces

2008

In this paper we prove some common fixed point theorems for fuzzy contraction respect to a mapping, which satisfies a condition of weak compatibility. We deduce also fixed point results for fuzzy contractive mappings in the sense of Gregori and Sapena.

Discrete mathematicsFuzzy metric spaceGeneral MathematicsFixed pointFixed-point propertyFuzzy logicFuzzy metric spaceLeast fixed pointPoints of coincidenceCommon fixed pointSettore MAT/05 - Analisi MatematicaFixed-point iterationCommon fixed pointDiscontinuous mappingCoincidence pointMathematicsRendiconti del Circolo Matematico di Palermo
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