We define what it means to be a Hausdorff space. Then we show that in Hausdorff spaces finite sets are closed, limits of convergent sequences are unique, and neighborhoods of limit points intersect the limiting set in infinitely many points.
00:00 Introduction
00:19 Motivation for Hausdorff Property
08:58 Definition: Hausdorff Space
09:35 Example: Metric Spaces
13:00 Example: Discrete Spaces
14:18 Prop: Finite subsets of Hausdorff spaces are closed
19:42 Prop: Limits are unique in Hausdorff spaces
24:50 Prop: Neighborhoods of limit points contain infinitely many points of limiting set
This lecture follows Lee's "Introduction to topological manifolds", chapter 2.
A playlist with all the videos in this series can be found here:
• Topology
22 Comments