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1. $A\times B$ is not the coproduct of $A$ and $B$ in Rel.

Anonymous

• CommentRowNumber2.
• CommentAuthorGuest
• CommentTimeNov 15th 2021
• CommentRowNumber3.
• CommentAuthorGuest
• CommentTimeApr 18th 2022
Are there any sources for SEAR in the existing mathematical literature, or is this all original research?
• CommentRowNumber4.
• CommentAuthorDavidRoberts
• CommentTimeApr 19th 2022

This is all Mike’s original research, and as far as I know, the nLab is the only place this appears in detail (I believe it may be cited/referred to in various places).

• CommentRowNumber5.
• CommentAuthorGuest
• CommentTimeApr 19th 2022
well, I guess it's up for somebody else to publish in formal journals an "Elementary Theory of the Bicategory of Relations Between Sets"
• CommentRowNumber6.
• CommentAuthorHurkyl
• CommentTimeApr 19th 2022
• (edited Apr 19th 2022)

Self-deleted. (re: the notion of allegory is just ’sets and relations’, without the E part)

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