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    • CommentRowNumber1.
    • CommentAuthorUrs
    • CommentTimeNov 23rd 2011

    I have created a list discrete and concrete objects - contents to be used as a “floating TOC” and have included it into relevant entries.

    In this context I have also created concrete object, co-concrete object and discrete object and codiscrete object redirect to the existing discrete space and codiscrete space.

    • CommentRowNumber2.
    • CommentAuthorMike Shulman
    • CommentTimeJan 12th 2015

    The page co-concrete object doesn’t appear to actually contain a definition of co-concrete objects.

    • CommentRowNumber3.
    • CommentAuthorUrs
    • CommentTimeJan 12th 2015

    Thanks for the alert. Hm, I forget what the definition was even supposed to be. Maybe objects XX for which XX\flat X\to X is an epi? (Which is one kind of dual to the condition for concrete objects viz. XXX \to \sharp X a mono.)

    • CommentRowNumber4.
    • CommentAuthorMike Shulman
    • CommentTimeJan 12th 2015

    That was my guess upon encountering the term.

    • CommentRowNumber5.
    • CommentAuthorUrs
    • CommentTimeJan 13th 2015

    Okay, I have edited the entry accordingly.