Search results for "Theorem"

Common fixed point theorems for families of occasionally weakly compatible mappings

2011

We prove some common fixed point theorems in probabilistic semi-metric spaces for families of occasionally weakly compatible mappings. We also give a common fixed point theorem for mappings satisfying an integral-type implicit relation.

Common fixed points of mappings satisfying implicit contractive conditions

2012

In this article we obtain, in the setting of metric spaces or ordered metric spaces, coincidence point, and common fixed point theorems for self-mappings in a general class of contractions defined by an implicit relation. Our results unify, extend, generalize many related common fixed point theorems from the literature. Mathematics Subject Classification (2000): 47H10, 54H25.

A Coupled Fixed Point Theorem in Fuzzy Metric Space Satisfying ϕ-Contractive Condition

2013

The intent of this paper is to prove a coupled fixed point theorem for two pairs of compatible and subsequentially continuous (alternately subcompatible and reciprocally continuous) mappings, satisfyingϕ-contractive conditions in a fuzzy metric space. We also furnish some illustrative examples to support our results.

WQ*-algebras of measurable operators

2012

Every C*-algebra \(\mathfrak{A}\) has a faithful *-representation π in a Hilbert space \(\mathcal{H}\). Consequently it is natural to pose the following question: under which conditions, the completion of a C*-algebra in a weaker than the given one topology, can be realized as a quasi *-algebra of operators? The present paper presents the possibility of extending the well known Gelfand — Naimark representation of C*-algebras to certain Banach C*-modules.

On second maximal subgroups of Sylow subgroups of finite groups

2011

Abstract Finite groups in which the second maximal subgroups of the Sylow p -subgroups, p a fixed prime, cover or avoid the chief factors of some of its chief series are completely classified.

Sylow numbers and nilpotent Hall subgroups

2013

Abstract Let π be a set of primes and G a finite group. We characterize the existence of a nilpotent Hall π-subgroup of G in terms of the number of Sylow subgroups for the primes in π.

Counterexamples to the Algebraic Closed Graph Theorem

1982

A Periodicity Theorem on Words and Applications

1995

We prove a periodicity theorem on words that has strong analogies with the Critical Factorization theorem and we show three applications of it.

Periodic and quasi-periodic orbits of the dissipative standard map

2011

We present analytical and numerical investigations of the dynamics of the dissipative standard map. We first study the existence of periodic orbits by using a constructive version of the implicit function theorem; then, we introduce a parametric representation, which provides the interval of the drift parameter ensuring the existence of a periodic orbit with a given period. The determination of quasi--periodic attractors is efficiently obtained using the parametric representation combined with a Newton's procedure, aimed to reduce the error of the approximate solution provided by the parametric representation. These methods allow us to relate the drift parameter of the periodic orbits to th…

Sharpness of Rickman’s Picard theorem in all dimensions

2015

We show that given \({n \geqslant 3}\), \({q \geqslant 1}\), and a finite set \({\{y_1, \ldots, y_q \}}\) in \({\mathbb{R}^n}\) there exists a quasiregular mapping \({\mathbb{R}^n\to \mathbb{R}^n}\) omitting exactly points \({y_1, \ldots, y_q}\).