Lusternik–Schnirelmann category
id:
lusternik-schnirelmann-category-275-15246368
title:
Lusternik–Schnirelmann category
text:
In mathematics, the Lyusternik–Schnirelmann category of a topological space X is the homotopy invariant defined to be the smallest integer number k such that there is an open covering { U i } 1 ≤ i ≤ k of X with the property that each inclusion map U i ↪ X is nullhomotopic. For example, if X is a sphere, this takes the value two. Sometimes a different normalization of the invariant is adopted, which is one less than the definition above. Such a normalization has been adopted in the definitive mo
brand slug:
wiki
category slug:
encyclopedia
description:
original url:
https://en.wikipedia.org/wiki/Lusternik%E2%80%93Schnirelmann_category
date created:
date modified:
2019-08-09T12:33:38Z
main entity:
{"identifier":"Q2361277","url":"https://www.wikidata.org/entity/Q2361277"}
image:
fields total:
13
integrity:
13