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  1. A×BA\times B is not the coproduct of AA and BB in Rel.

    Anonymous

    diff, v56, current

    • 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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