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1. • CommentRowNumber1.
   • CommentAuthorNoam_Zeilberger
   • CommentTimeJan 31st 2016
   • (edited Jan 31st 2016)
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   Author: Noam_Zeilberger
   Format: MarkdownItexI'm thinking of creating a little page called [[rigid object]] about the property of an object of a category having no non-trivial automorphisms. How standard is this terminology? I've seen it used in a few places, for example in [this paper by Kock et al.](http://arxiv.org/pdf/0706.1033v2.pdf). On the other hand, it seems that "rigid object" is also sometimes used to refer to an object of a monoidal category with both left and right duals, as in a [[rigid monoidal category]]. Is there any connection between these two usages?

   I’m thinking of creating a little page called rigid object about the property of an object of a category having no non-trivial automorphisms. How standard is this terminology? I’ve seen it used in a few places, for example in this paper by Kock et al.. On the other hand, it seems that “rigid object” is also sometimes used to refer to an object of a monoidal category with both left and right duals, as in a rigid monoidal category. Is there any connection between these two usages?

2. • CommentRowNumber2.
   • CommentAuthorTodd_Trimble
   • CommentTimeJan 31st 2016
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   Author: Todd_Trimble
   Format: MarkdownItexThat terminology is very standard as far as I'm concerned, but I very much doubt there's any significant connection between those two usages. My opinion is that it would be good to create such a page.

   That terminology is very standard as far as I’m concerned, but I very much doubt there’s any significant connection between those two usages. My opinion is that it would be good to create such a page.

3. • CommentRowNumber3.
   • CommentAuthorNoam_Zeilberger
   • CommentTimeFeb 1st 2016
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   Author: Noam_Zeilberger
   Format: MarkdownItexOK, I went ahead and made a start at [[rigid object]].

   OK, I went ahead and made a start at rigid object.

4. • CommentRowNumber4.
   • CommentAuthorTodd_Trimble
   • CommentTimeFeb 1st 2016
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   Author: Todd_Trimble
   Format: MarkdownItexI added a little bit about rigid spaces.

   I added a little bit about rigid spaces.

5. • CommentRowNumber5.
   • CommentAuthorMike Shulman
   • CommentTimeFeb 2nd 2016
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   Author: Mike Shulman
   Format: MarkdownItexI added a generalization to higher categories, and an example of Eilenberg--MacLane spaces of symmetric groups.

   I added a generalization to higher categories, and an example of Eilenberg–MacLane spaces of symmetric groups.

6. • CommentRowNumber6.
   • CommentAuthorNoam_Zeilberger
   • CommentTimeFeb 2nd 2016
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   Author: Noam_Zeilberger
   Format: MarkdownItexThanks for adding these examples, Todd and Mike!

   Thanks for adding these examples, Todd and Mike!