Is Every Metric Space Hausdorff?

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The discussion centers on the assumption that a metric space's topology is generated by its metric, which is crucial for the theorem stating that every metric space is Hausdorff. When an alternative topology, such as the trivial topology, is applied, the space may not be Hausdorff despite the metric remaining unchanged. This raises questions about the clarity of the theorem's statement and whether it adequately specifies the topology in use. Participants emphasize that without explicitly stating the topology, the assumption defaults to the one generated by the metric. Overall, the conversation highlights the importance of clarity in mathematical definitions and assumptions.
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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?
 
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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:
 

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