Is Every Metric Space Hausdorff?

Dead Boss
Messages
150
Reaction score
1
The usual proof of this theorem seems to assume that the topology of the metric space is the one generated by the metric. But if I use another topology, for example the trivial, the space need not be Hausdorff but the metric stays the same. Am I missing something or is the statement of the theorem just sloppy?
 
Physics news on Phys.org
If you say that you have a metric space (X,d), then it is always assumed that we take the topology generated by the metric. If we happen to take another topology, then we always state this explicitely.

It's the same as saying that you work with \mathbb{R}^n. The topology is always assumed to be Euclidean unless otherwise stated.
 
Thanks. :smile:
 
A sphere as topological manifold can be defined by gluing together the boundary of two disk. Basically one starts assigning each disk the subspace topology from ##\mathbb R^2## and then taking the quotient topology obtained by gluing their boundaries. Starting from the above definition of 2-sphere as topological manifold, shows that it is homeomorphic to the "embedded" sphere understood as subset of ##\mathbb R^3## in the subspace topology.
Back
Top