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1. • CommentRowNumber1.
   • CommentAuthorUrs
   • CommentTimeMar 26th 2010
   • (edited Mar 26th 2010)
   • PermaLink
   Author: Urs
   Format: Markdownthere have been recent edits at [[partially ordered dagger category]]. i edited a bit in an attempt to polish. Tim Porter mentions parially ordered groupoids here. I am not sure why. These are not dagger categories, are they? This should go in another entry then, I suppose?

   there have been recent edits at partially ordered dagger category. i edited a bit in an attempt to polish.

   Tim Porter mentions parially ordered groupoids here. I am not sure why. These are not dagger categories, are they? This should go in another entry then, I suppose?

2. • CommentRowNumber2.
   • CommentAuthorIan_Durham
   • CommentTimeMar 26th 2010
   • PermaLink
   Author: Ian_Durham
   Format: HtmlOops. Spelled "ordered" wrong. Should be [[partially ordered dagger category]].

   Oops. Spelled "ordered" wrong. Should be partially ordered dagger category.
3. • CommentRowNumber3.
   • CommentAuthorTim_Porter
   • CommentTimeMar 27th 2010
   • PermaLink
   Author: Tim_Porter
   Format: MarkdownPerhaps one should have [[partially ordered category]] separated from [[partially ordered dagger category]]. @Urs: I do not quite see what you mean. Looking at the definition of dagger cat., it seemed to me that a groupoid gave an example of one. Am I confused? The type of ordered groupoid that Lawson looks at is the groupoid of partial symmetries of a set. The objects are the subsets of a set X and the morphisms are the bijections. The order relation is about one bijection being the restriction of another. Doesn't that give an example .... I am not thinking clearly and need another coffee so I may be confused. (Alternatively I may have had too may coffees!!)

   Perhaps one should have partially ordered category separated from partially ordered dagger category.

   @Urs: I do not quite see what you mean. Looking at the definition of dagger cat., it seemed to me that a groupoid gave an example of one. Am I confused?

   The type of ordered groupoid that Lawson looks at is the groupoid of partial symmetries of a set. The objects are the subsets of a set X and the morphisms are the bijections. The order relation is about one bijection being the restriction of another.

   Doesn't that give an example .... I am not thinking clearly and need another coffee so I may be confused. (Alternatively I may have had too may coffees!!)

4. • CommentRowNumber4.
   • CommentAuthorUrs
   • CommentTimeMar 27th 2010
   • PermaLink
   Author: Urs
   Format: Markdown> I do not quite see what you mean. Looking at the definition of dagger cat., it seemed to me that a groupoid gave an example of one. Am I confused? I guess you are right, I didn't think about it. Let's just make it clear in the entry what's going on.

   I do not quite see what you mean. Looking at the definition of dagger cat., it seemed to me that a groupoid gave an example of one. Am I confused?

   I guess you are right, I didn't think about it. Let's just make it clear in the entry what's going on.