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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 $X \stackrel{\simeq}{\leftarrow} \hat X \to Y$.

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 $X \stackrel{\simeq}{\leftarrow} \hat X \to Y$.

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?

• 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.

• CommentRowNumber14.
• CommentAuthorUrs
• CommentTimeJul 27th 2021