Talk:Separable sigma algebra

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No, this is called "countably generated", not "separable". Also it is not clear whether all that is about a measurable space (no measure given, just a sigma-algebra) or a measure space (a measure is given). Boris Tsirelson (talk) 21:42, 10 February 2012 (UTC)[reply]

Note that any σ-algebra generated by a countable collection of sets is countable, but the converse need not hold.

This seems simply wrong to me. See for example math.stackexchange. 80.108.41.157 (talk) 22:02, 17 December 2013 (UTC)[reply]

Sure, this is evidently wrong: the Borel σ-algebra is countably generated but contains a continuum of intervals (and other sets). I correct it. Boris Tsirelson (talk) 06:54, 20 December 2013 (UTC)[reply]