local compactness

См. также в других словарях:

• Compact space — Compactness redirects here. For the concept in first order logic, see compactness theorem. In mathematics, specifically general topology and metric topology, a compact space is an abstract mathematical space whose topology has the compactness… …   Wikipedia

• Protein domain — Pyruvate kinase, a protein from three domains (PDB 1pkn) A protein domain is a part of protein sequence and structure that can evolve, function, and exist independently of the rest of the protein chain. Each domain forms a compact three… …   Wikipedia

• Countably compact space — In mathematics a topological space is countably compact if every countable open cover has a finite subcover. Examples and Properties A compact space is countably compact. Indeed, directly from the definitions, a space is compact if and only if it …   Wikipedia

• Locally compact space — In topology and related branches of mathematics, a topological space is called locally compact if, roughly speaking, each small portion of the space looks like a small portion of a compact space.Formal definitionLet X be a topological space. The… …   Wikipedia

• Hausdorff space — In topology and related branches of mathematics, a Hausdorff space, separated space or T2 space is a topological space in which distinct points have disjoint neighbourhoods. Of the many separation axioms that can be imposed on a topological space …   Wikipedia

• Σ-compact space — In mathematics, a topological space is said to be sigma; compact if it is the union of countably many compact subspaces. A space is said to be sigma; locally compact if it is both sigma; compact and locally compact.Properties and Examples* Every… …   Wikipedia

• Riesz's lemma — is an lemma in functional analysis. It specifies (often easy to check) conditions which guarantee that a subspace in a normed linear space is dense. The result Before stating the result, we fix some notation. Let X be a normed linear space with… …   Wikipedia

• Regular space — In topology and related fields of mathematics, regular spaces and T3 spaces are particularly convenient kinds of topological spaces.Both conditions are examples of separation axioms. Definitions Suppose that X is a topological space. X is a… …   Wikipedia

• C*-algebra — C* algebras (pronounced C star ) are an important area of research in functional analysis, a branch of mathematics. The prototypical example of a C* algebra is a complex algebra A of linear operators on a complex Hilbert space with two additional …   Wikipedia

• Locally compact group — In mathematics, a locally compact group is a topological group G which is locally compact as a topological space. Locally compact groups are important because they have a natural measure called the Haar measure. This allows one to define… …   Wikipedia

• Perfect map — In mathematics, particularly topology, a perfect map is a map which preserves inverse like properties. Just as the continuous image of a connected space is always connected, if the perfect image (image under a perfect map) of a certain space X is …   Wikipedia