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    • CommentRowNumber1.
    • CommentAuthorUrs
    • CommentTimeSep 4th 2010

    added a list of examples to Lie groupoid

    • CommentRowNumber2.
    • CommentAuthorUrs
    • CommentTimeSep 4th 2010

    I saw some loose ends and made some half-hearted attempts to start filling them without really having time for this. But I created stubs for

    and

    • CommentRowNumber3.
    • CommentAuthorJohn Baez
    • CommentTimeJul 24th 2011

    In Lie groupoid I changed

    One way to deal with this is to equip the 2-category with some structure of a homotopical category and allow morphisms of Lie groupoids to be 2-anafunctors, i.e. spans of internal functors XX^YX \stackrel{\simeq}{\leftarrow} \hat X \to Y.

    to

    One way to deal with this is to equip the 2-category with some structure of a homotopical category and allow morphisms of Lie groupoids to be anafunctors, i.e. spans of internal functors XX^YX \stackrel{\simeq}{\leftarrow} \hat X \to Y.

    If it’s wrong, change it back and let me know the error of my ways!

    (I’m writing a little paper with Derek Wise on gravity and higher gauge theory, and I was looking for standard references on Lie groupoids…)

    • CommentRowNumber4.
    • CommentAuthorTobyBartels
    • CommentTimeJul 24th 2011

    You’re correct!

    • CommentRowNumber5.
    • CommentAuthorUrs
    • CommentTimeMay 20th 2019

    I was looking for any online incarnation of

    • Charles Ehresmann, Catégories topologiques et catégories différentiables, Colloque de Géometrie Differentielle Globale (Bruxelles, 1958), 137–150, Centre Belge Rech. Math., Louvain, 1959;

    such as a doi, or a jstor entry. Anything?

    diff, v62, current

    • CommentRowNumber6.
    • CommentAuthorTim_Porter
    • CommentTimeMay 20th 2019

    Try page 263 of http://ehres.pagesperso-orange.fr/C.E.WORKS_fichiers/Ehresmann_C.-Oeuvres_I-1_et_I-2.pdf, i.e. Ehresmann’s collected works. I think that is what you need.

    • CommentRowNumber7.
    • CommentAuthorUrs
    • CommentTimeMay 20th 2019

    Thanks. Might you know which page in that big file corresponds to the above article?

    (It doesn’t seem to be searchable…)

    • CommentRowNumber8.
    • CommentAuthorDavidRoberts
    • CommentTimeMay 20th 2019

    I’ll send you a copy of the paper itself, Urs.

    • CommentRowNumber9.
    • CommentAuthorUrs
    • CommentTimeMay 20th 2019

    Thanks, but I don’t need to read the paper myself, instead I want to cite it in a way that is useful to others. May we upload it here?

    • CommentRowNumber10.
    • CommentAuthorTim_Porter
    • CommentTimeMay 20th 2019
    • (edited May 20th 2019)

    Why not give the link and then add ’starting on page 263’?

    Is there a link to the collected works somewhere on the Lab? If not it may be worth while adding.

    • CommentRowNumber11.
    • CommentAuthorUrs
    • CommentTimeMay 20th 2019

    Hi Tim, ah, thanks for saying that again, had missed that. Okay, am adding the pointer to this now.

    (If this is online, I guess David’s more tractable copy may be put online, too. But it has a scary all-capital copyright WARNING right at the beginning, which intimidates even me… )

    • CommentRowNumber12.
    • CommentAuthorDavidRoberts
    • CommentTimeMay 20th 2019
    • (edited May 20th 2019)

    Yeah, please don’t upload my copy. I did get it under careful arrangements before the whole lot was scanned and put online. I think pointing to the official copy should be sufficient for now. My only worry was that the scanning had gone wrong (like on a few other pages) but I checked and it’s ok.

    • CommentRowNumber13.
    • CommentAuthorUrs
    • CommentTimeMay 20th 2019

    Sure. Okay, thanks.

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