Concept

Sequentially complete

In mathematics, specifically in topology and functional analysis, a subspace S of a uniform space X is said to be sequentially complete or semi-complete if every Cauchy sequence in S converges to an element in S. X is called sequentially complete if it is a sequentially complete subset of itself. Every topological vector space is a uniform space so the notion of sequential completeness can be applied to them. A bounded sequentially complete disk in a Hausdorff topological vector space is a Banach disk. A Hausdorff locally convex space that is sequentially complete and bornological is ultrabornological. Every complete space is sequentially complete but not conversely. A metrizable space then it is complete if and only if it is sequentially complete. Every complete topological vector space is quasi-complete and every quasi-complete topological vector space is sequentially complete.

Source officielle

https://en.wikipedia.org/wiki/Sequentially_complete

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Séances de cours associées (1)

Analyse fonctionnelle : Banach et Hilbert Spaces

Couvre les espaces de Banach et de Hilbert, la séparabilité, la norme, la continuité et l'analyse fonctionnelle.

Publications associées (1)

A general framework for homotopic descent and codescent

Kathryn Hess Bellwald

In this paper we elaborate a general homotopy-theoretic framework in which to study problems of descent and completion and of their duals, codescent and cocompletion. Our approach to homotopic (co)descent and to derived (co)completion can be viewed as $\in ...

2010

Concepts associés (2)

Bornological space

In mathematics, particularly in functional analysis, a bornological space is a type of space which, in some sense, possesses the minimum amount of structure needed to address questions of boundedness of sets and linear maps, in the same way that a topological space possesses the minimum amount of structure needed to address questions of continuity. Bornological spaces are distinguished by the property that a linear map from a bornological space into any locally convex spaces is continuous if and only if it is a bounded linear operator.

Complete topological vector space

In functional analysis and related areas of mathematics, a complete topological vector space is a topological vector space (TVS) with the property that whenever points get progressively closer to each other, then there exists some point towards which they all get closer. The notion of "points that get progressively closer" is made rigorous by or , which are generalizations of , while "point towards which they all get closer" means that this Cauchy net or filter converges to The notion of completeness for TVSs uses the theory of uniform spaces as a framework to generalize the notion of completeness for metric spaces.