Search results for "FIX"

showing 10 items of 1335 documents

Uniformly nonsquare Banach spaces have the fixed point property for nonexpansive mappings

2006

Abstract It is shown that if the modulus Γ X of nearly uniform smoothness of a reflexive Banach space satisfies Γ X ′ ( 0 ) 1 , then every bounded closed convex subset of X has the fixed point property for nonexpansive mappings. In particular, uniformly nonsquare Banach spaces have this property since they are properly included in this class of spaces. This answers a long-standing question in the theory.

Discrete mathematicsMathematics::Functional AnalysisPure mathematicsUniformly nonsquare spacesApproximation propertyEberlein–Šmulian theoremBanach spaceNonexpansive mappingsUniformly convex spaceBanach manifoldFixed-point propertyNearly uniform smoothnessFixed pointsReflexive spaceLp spaceAnalysisMathematicsJournal of Functional Analysis
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Fixed point results on metric and partial metric spaces via simulation functions

2015

We prove existence and uniqueness of fixed point, by using a simulation function and a lower semi-continuous function in the setting of metric space. As consequences of this study, we deduce several related fixed point results, in metric and partial metric spaces. An example is given to support the new theory.

Discrete mathematicsMetric spaceNonlinear contractionAlgebra and Number TheoryPartial metric spaceSimulation functionSettore MAT/05 - Analisi MatematicaMetric (mathematics)Fixed pointFixed pointMetric spaceAnalysisMathematics
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On fixed points for a–n–f-contractive multi-valued mappings in partial metric spaces

2015

Recently, Samet et al. introduced the notion of α-ψ-contractive type mappings and established some fixed point theorems in complete metric spaces. Successively, Asl et al. introduced the notion of αӿ-ψ-contractive multi-valued mappings and gave a fixed point result for these multivalued mappings. In this paper, we establish results of fixed point for αӿ-admissible mixed multivalued mappings with respect to a function η and common fixed point for a pair (S; T) of mixed multi-valued mappings, that is, αӿ-admissible with respect to a function η in partial metric spaces. An example is given to illustrate our result.

Discrete mathematicsMetric spacePartial metric spaceSettore MAT/05 - Analisi MatematicaApplied Mathematicsαӿ-admissible pair with respect to a function ηFixed pointFixed pointα-η-ψ-contractive conditionCommon fixed pointMulti valuedAnalysisMathematicsNonlinear Analysis: Modelling and Control
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Common fixed point theorems for multi-valued maps

2012

Abstract We establish some results on coincidence and common fixed points for a two-pair of multi-valued and single-valued maps in complete metric spaces. Presented theorems generalize recent results of Gordji et al [4] and several results existing in the literature.

Discrete mathematicsMetric spaceSettore MAT/05 - Analisi MatematicaGeneral MathematicsCommon fixed pointGeneral Physics and AstronomyCoincidence point common fixed point multi-valued mapsFixed pointCoincidence pointMulti valuedCoincidenceMathematics
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Meir-Keeler Type Contractions for Tripled Fixed Points

2012

Abstract In 2011, Berinde and Borcut [6] introduced the notion of tripled fixed point in partially ordered metric spaces. In our paper, we give some new tripled fixed point theorems by using a generalization of Meir-Keeler contraction.

Discrete mathematicsMetric spaceSettore MAT/05 - Analisi MatematicaGeneralizationGeneral MathematicsMathematics::General TopologyGeneral Physics and AstronomyFixed-point theoremTripled fixed point theorems Meir-Keeler type contractions partially ordered sets.Type (model theory)Fixed pointPartially ordered setMathematicsActa Mathematica Scientia
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Metric or partial metric spaces endowed with a finite number of graphs: a tool to obtain fixed point results

2014

Abstract We give some fixed point theorems in the setting of metric spaces or partial metric spaces endowed with a finite number of graphs. The presented results extend and improve several well-known results in the literature. In particular, we discuss a Caristi type fixed point theorem in the setting of partial metric spaces, which has a close relation to Ekelandʼs principle.

Discrete mathematicsMetric spaceUniform continuityInjective metric spaceCaristi's fixed point theorem Ekeland's principle graph metric space partial metric space.Metric mapMetric treeGeometry and TopologyEquivalence of metricsSettore MAT/03 - GeometriaConvex metric spaceMathematicsIntrinsic metric
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Brauer characters and coprime action

2016

Abstract It is an open problem to show that under a coprime action, the number of invariant Brauer characters of a finite group is the number of the Brauer characters of the fixed point subgroup. We prove that this is true if the non-abelian simple groups satisfy a stronger condition.

Discrete mathematicsModular representation theoryPure mathematicsFinite groupAlgebra and Number TheoryBrauer's theorem on induced charactersCoprime integers010102 general mathematics02 engineering and technologyFixed point021001 nanoscience & nanotechnology01 natural sciencesSimple group0101 mathematicsInvariant (mathematics)Mathematics::Representation Theory0210 nano-technologyBrauer groupMathematicsJournal of Algebra
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Periodicity vectors for labelled trees

2003

AbstractThe concept of a periodicity vector is introduced in the context of labelled trees, and some new periodicity theorems are obtained. These results constitute generalizations of the classical periodicity theorem of Fine and Wilf for words. The concept of a tree congruence is also generalized and the isomorphism between the lattice of tree congruences and the lattice of unlabelled trees (prefix codes) is established.

Discrete mathematicsMonoidPrefix codePeriodicityApplied MathematicsContext (language use)Congruence relationTree (graph theory)CombinatoricsFormal languagesLattice (music)Labelled treeCongruence (manifolds)Periodicity vectorDiscrete Mathematics and CombinatoricsIsomorphismMathematicsDiscrete Applied Mathematics
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Partial Hausdorff metric and Nadler’s fixed point theorem on partial metric spaces

2012

Abstract In this paper, we introduce the concept of a partial Hausdorff metric. We initiate study of fixed point theory for multi-valued mappings on partial metric space using the partial Hausdorff metric and prove an analogous to the well-known Nadlerʼs fixed point theorem. Moreover, we give a homotopy result as application of our main result.

Discrete mathematicsNadlerʼs fixed point theoremPure mathematicsInjective metric spacePartial Hausdorff metricMulti-valued mappingsNadler’s fixed point theoremMulti-valued mappingConvex metric spaceIntrinsic metricMetric spaceHausdorff distanceSettore MAT/05 - Analisi MatematicaHausdorff dimensionHausdorff measureGeometry and TopologyMetric differentialMathematics
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Semi-compatible and reciprocally continuous maps in weak non-Archimedean Menger PM-spaces

2012

In this paper, we introduce semi-compatible maps and reciprocally continuous maps in weak non-Archimedean PM-spaces and establish a common fixed point theorem for such maps. Moreover, we show that, in the context of reciprocal continuity, the notions of compatibility and semi-compatibility of maps become equivalent. Our result generalizes several fixed point theorems in the sense that all maps involved in the theorem can be discontinuous even at the common fixed point.

Discrete mathematicsNon-Archimedean Menger Space Compatible Semi compatible Weakly compatible Reciprocally continuousWeakly compatibleSettore MAT/05 - Analisi MatematicaGeneral MathematicsCompatibility (mechanics)Common fixed pointFixed-point theoremCommon fixed point theoremReciprocalMathematics
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