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Timeline for Sheaf description of $G$-bundles

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Dec 2, 2019 at 8:52 comment added ACL @LSpice, it is at the beginning of section III (Interlude: Review of algebraic groups), page 211. The statement of Chevalley's theorem is on page 212. The key word is “construction”. (I imagine it shortens the expression “construction tensorielle”.)
Dec 1, 2019 at 3:05 comment added LSpice @ACL, do you happen to remember where in Katz - A conjecture in the arithmetic theory of differential equations that result appears? The word 'tensor' appears 4 times in the paper, and none of them seems obviously to be the quoted result.
S May 4, 2016 at 15:47 history suggested Armando j18eos CC BY-SA 3.0
I had correct the code!
May 4, 2016 at 15:37 review Suggested edits
S May 4, 2016 at 15:47
Jan 31, 2014 at 9:19 comment added ACL @AntonGeraschenko: I learnt this in Katz's paper on (Bulletin SMF, 1982, numdam.org/item?id=BSMF_1982__110__203_0). He refers to Chevalley's 1968 book on Lie groups.
Jan 30, 2014 at 23:14 comment added Anton Geraschenko @ACL: Can you give me a reference for that? At some point I tried describing what sorts of tensor relations give a vector space the structure of a representation of given a finite group, but I didn't get anything I was happy with. I didn't know that there was a general result along these lines for affine algebraic groups.
Jan 30, 2014 at 7:44 comment added ACL @Anton: Algebraic subgroups of $GL(n)$ can be described by matrices fixing some tensor; consequently, $G$-bundles can be described as a vector bundle + some tensors.
Jan 30, 2014 at 4:56 history edited Anton Geraschenko CC BY-SA 3.0
Correction: Aut(F) should have been Isom(O^n, F). While I'm here, texifying and cleaning up a couple of stylistic things.
Oct 25, 2009 at 16:00 comment added Charles Siegel This is the closest to the sort of thing I was looking for. Since asking, I realized that there was an obvious description that was what I was looking for, for any fiber bundle with fiber F, a locally trivial F-bundle should be (it's in my scratch notebook, not fully proved but should work) equivalent to a sheaf of sets locally isomorphic to sheaf Hom(X,F). This recovers the equivalence for vector bundles, and does about what I want for G-bundles.
Oct 25, 2009 at 15:59 vote accept Charles Siegel
Oct 25, 2009 at 4:37 history edited Anton Geraschenko CC BY-SA 2.5
added 342 characters in body
Oct 25, 2009 at 4:01 history answered Anton Geraschenko CC BY-SA 2.5