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.
This article includes a list of general references, but it lacks sufficient corresponding inline citations. (May 2020) |
Sequentially complete topological vector spaces
Every topological vector space is a uniform space so the notion of sequential completeness can be applied to them.
Properties of sequentially complete topological vector spaces
- A bounded sequentially complete disk in a Hausdorff topological vector space is a Banach disk.[1]
- A Hausdorff locally convex space that is sequentially complete and bornological is ultrabornological.[2]
Examples and sufficient conditions
- Every complete space is sequentially complete but not conversely.
- For metrizable spaces, sequential completeness implies completeness. Together with the previous property, this means sequential completeness and completeness are equivalent over metrizable spaces.
- Every complete topological vector space is quasi-complete and every quasi-complete topological vector space is sequentially complete.[3]
See also
References
Bibliography
Wikiwand in your browser!
Seamless Wikipedia browsing. On steroids.
Every time you click a link to Wikipedia, Wiktionary or Wikiquote in your browser's search results, it will show the modern Wikiwand interface.
Wikiwand extension is a five stars, simple, with minimum permission required to keep your browsing private, safe and transparent.