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Anton Petrunin
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It is not exactly the same: even if all bounded subsets are totally bounded, there might be bounded sequence contains a Cauchy subsequence. But if you assume that the space is complete, then it is the same.

Proper space is the a complete space such that any bounded subset is totally bounded,

  • or equivalently, in which any bounded sequence contains a Cauchy subsequence,
  • or equivalently, any bounded closed set is compace,
  • or equivalently, the distance function from one (and therefore any) point is proper; the latter means that invese image of any compact set is compact.
Anton Petrunin
  • 45k
  • 14
  • 135
  • 299