skip to main content
LOTERRE

LOTERRE

Choisissez le vocabulaire dans lequel chercher

Langue des données

| español English
Aide à la recherche

Concept information

topology > general topology > compactness

Terme préférentiel

compactness  

Définition(s)

  • In mathematics, specifically general topology, compactness is a property that seeks to generalize the notion of a closed and bounded subset of Euclidean space. The idea is that a compact space has no "punctures" or "missing endpoints", i.e., it includes all limiting values of points. For example, the open interval (0,1) would not be compact because it excludes the limiting values of 0 and 1, whereas the closed interval [0,1] would be compact. Similarly, the space of rational numbers Q is not compact, because it has infinitely many "punctures" corresponding to the irrational numbers, and the space of real numbers R is not compact either, because it excludes the two limiting values + ∞ and − ∞. However, the extended real number line would be compact, since it contains both infinities. There are many ways to make this heuristic notion precise. These ways usually agree in a metric space, but may not be equivalent in other topological spaces.
    (Wikipedia, The Free Encyclopedia, https://en.wikipedia.org/wiki/Compact_space)

Concept(s) générique(s)

Synonyme(s)

  • compact space

Traductions

URI

http://data.loterre.fr/ark:/67375/PSR-MPQHSB53-6

Télécharger ce concept:

RDF/XML TURTLE JSON-LD Date de création 21/07/2023, dernière modif. 22/09/2023