Compactness

From Maths
Revision as of 14:23, 13 February 2015 by Alec (Talk | contribs) (Created page with " ==Definition== A topological space is compact if every open cover (often denoted <math>\mathcal{A}</math>) of <math>X</math> contains...")

(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to: navigation, search

Definition

A topological space is compact if every open cover (often denoted [math]\mathcal{A}[/math]) of [math]X[/math] contains a finite sub-collection that also covers [math]X[/math]

Lemma for a set being compact


TODO: Note: details on Munkres p164