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Mark
  • Member for 13 years, 9 months
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49 votes
7 answers
5k views

Is there an algebraic approach to metric spaces?

22 votes
5 answers
2k views

Which norms have rich isometry groups?

9 votes
2 answers
968 views

Which Banach algebras are group algebras?

20 votes
8 answers
11k views

Nice applications of the spectral theorem?

7 votes
2 answers
1k views

Decomposing an arbitrary unitary representation of a connected nilpotent Lie group in terms of its irreps

67 votes
11 answers
10k views

How should one think about non-Hausdorff topologies?

10 votes
1 answer
1k views

Which groups can be recovered from their unitary dual?

5 votes
2 answers
705 views

Conditions on a metric space so that boundedness implies total boundedness

19 votes
5 answers
3k views

The definition of homotopy in algebraic topology

3 votes
1 answer
2k views

Does the category of Hilbert spaces possess a product?

175 votes
7 answers
29k views

Why do probabilists take random variables to be Borel (and not Lebesgue) measurable?