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1. • CommentRowNumber1.
   • CommentAuthorUrs
   • CommentTimeApr 30th 2017
   • (edited May 1st 2017)
   • PermaLink
   Author: Urs
   Format: MarkdownItexI have touched the entry _[[K-topology]]_. Polished the definition and spelled out in some detail why it is not regular (while clearly Hausdorff). The example which used to be in the entry (rational numbers with their subspace K-topology [here](https://ncatlab.org/nlab/show/K-topology#RationalNumbersWithKTopology)) ends with > This space can be used to construct a quasitopological groupoid which isn’t a topological groupoid. This statement should be accompanied with some reference. I suppose it refers to a construction that David R. (who wrote this back in 2010, [rev #1](https://ncatlab.org/nlab/revision/K-topology/1)) used in one of his articles?

   I have touched the entry K-topology. Polished the definition and spelled out in some detail why it is not regular (while clearly Hausdorff).

   The example which used to be in the entry (rational numbers with their subspace K-topology here) ends with

   This space can be used to construct a quasitopological groupoid which isn’t a topological groupoid.

   This statement should be accompanied with some reference. I suppose it refers to a construction that David R. (who wrote this back in 2010, rev #1) used in one of his articles?

2. • CommentRowNumber2.
   • CommentAuthorDavidRoberts
   • CommentTimeApr 30th 2017
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   Author: DavidRoberts
   Format: MarkdownItexI can guess what the quasitopological grouped was meant to refer to (at least, I guess it was the fundamental groupoid with a topology on it), but I don't know why I link it to that example. Unless the action of the rationals on the reals with those topologies is only separately continuous. It can be taken out, I guess.

   I can guess what the quasitopological grouped was meant to refer to (at least, I guess it was the fundamental groupoid with a topology on it), but I don’t know why I link it to that example. Unless the action of the rationals on the reals with those topologies is only separately continuous. It can be taken out, I guess.