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    • CommentRowNumber1.
    • CommentAuthorDavid_Corfield
    • CommentTimeNov 24th 2011

    After Mike’s post, scone was created. But I see at Freyd cover it says

    The Freyd cover of a category – sometimes known as the Sierpinski cone or “scone” – is a special case of Artin gluing

    Are they synonyms?

    • CommentRowNumber2.
    • CommentAuthorTodd_Trimble
    • CommentTimeNov 25th 2011

    I don’t see that scone was created. At least, when I click on that link, I am invited to create an article on scone.

    • CommentRowNumber3.
    • CommentAuthorDavid_Corfield
    • CommentTimeNov 25th 2011

    OK, maybe the stage before creation, when Urs wrote this.

    Anyway, is it redundant?

    • CommentRowNumber4.
    • CommentAuthorUrs
    • CommentTimeNov 25th 2011
    • (edited Nov 25th 2011)

    Ah, sorry for causing confusion. I thought this was a common practice several of us had adopted: you say “It would be nice if a perfect entry existed” and the thing is:

    1. while it doesn’t yet, everyone following the link is actively asked to create it (so somebody might who otherwise wouldn’t);

    2. after it is created the link automatically points to a page with (hopefully) useful information.

    • CommentRowNumber5.
    • CommentAuthorzskoda
    • CommentTimeNov 25th 2011

    Is it supposed to be written with capital S for Sierpinski ? Scone or scone ?

    • CommentRowNumber6.
    • CommentAuthorTodd_Trimble
    • CommentTimeNov 25th 2011

    @Urs: there’s no confusion about that. I wasn’t ready to create an entry there myself, because I surely wanted to familiarize myself more with Mike’s post before attempting to say anything. I just thought that maybe David meant to point somewhere else on the nLab.

    Meanwhile, I have added material to Freyd cover, on Freyd’s neat sconing argument that the terminal object of the initial topos is connected and projective.

    @Zoran: Freyd, and everyone else I know about, writes ’scone’ (lower case).

    • CommentRowNumber7.
    • CommentAuthorMike Shulman
    • CommentTimeNov 25th 2011

    I made scone redirect to Freyd cover. Thanks Todd!

    • CommentRowNumber8.
    • CommentAuthorTim_Porter
    • CommentTimeNov 25th 2011
    • (edited Nov 25th 2011)

    Scones should be eaten with clotted Devon cream!! That is unless you are Scottish (in fact Scots in the true sense) in which it may mean the site of the Abbey where the ’clach-na-cinneamhain’ should be. (It is actually kept in Edinburgh castle except when needed for coronations!)

    • CommentRowNumber9.
    • CommentAuthorMike Shulman
    • CommentTimeJan 13th 2012

    Todd, do you know a reference for that argument of Freyd?

    • CommentRowNumber10.
    • CommentAuthorTodd_Trimble
    • CommentTimeJan 13th 2012

    Mike, it’s my amplification on what Freyd wrote in Categories, Allegories 1.(10)31 (page 192). (Maybe I should attribute it to Freyd-Scedrov; I’m merely imagining Freyd as having penned that.) I don’t know of another source off the bat.

    • CommentRowNumber11.
    • CommentAuthorMike Shulman
    • CommentTimeJan 13th 2012

    Ah, thanks! (Sadly, I don’t have a copy of that book.)