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    • CommentRowNumber1.
    • CommentAuthorDavid_Corfield
    • CommentTimeNov 12th 2021

    Since Inj had a link here, I started something.

    v1, current

    • CommentRowNumber2.
    • CommentAuthorUrs
    • CommentTimeNov 12th 2021

    Hm, it’s not clear that non-standard terminology for a trivial idea needs two separate pages, particularly if neither has anything interesting to say, so far.

    At least the entries should give references for where notation is used this way, if it is. I’d rather expect that if “Inj” is used for any category in the literature, then for subcategories of injective objects, but of course I haven’t made a survey.

    • CommentRowNumber3.
    • CommentAuthorDavid_Corfield
    • CommentTimeNov 14th 2021

    My attention was drawn to this by someone on Twitter asking for a name for the category, and finding Inj already here

    Let’s see, it’s there on p.720 of

    • John C. Baez, John Foley, Joe Moeller, and Blake S. Pollard, Network Models, Theory and Applications of Categories, Vol. 35, 2020, No. 20, pp 700-744, tac 35-20.

    But others use it for the category whose objects are injective set functions.

    Whatever we do, Inj is a page called by other pages, such as power set.

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