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Timeline for Sheaves and gratings

Current License: CC BY-SA 4.0

13 events
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Jul 12, 2023 at 15:32 vote accept coudy
Jul 12, 2023 at 15:23 comment added coudy @SimonWadsley Yes, I must have read too much in the paper. Thanks.
Jul 12, 2023 at 15:19 comment added Simon Wadsley I think he says global sections is what he has in mind: (copy and pasted with minor editing) "Inversement~ tout faisceau $F$ définit une carapace, à savoir le module des sections $\Gamma(F)$ . En effet, dans l’exposé 14 (numéro 1) on a défini des supports dans $\Gamma(F)$ ; et on vérifie aussitôt que les axiomes d’une carapace sont remplis. Pour tout faisceau $F$ et toute famille $\Phi$, $\Gamma_{\Phi}(F)$ est carapace."
Jul 12, 2023 at 15:10 comment added coudy @NicolasHemelsoet Yes, but then I guess this construction gives the module of global sections. Which probably is what Cartan had in mind.
Jul 12, 2023 at 15:03 comment added Nicolas Hemelsoet If you take the subset of the product consistued of "coherent sections" then property 1 seems to work no? The projection is the obvious one if $x \in U$ and 0 else.
Jul 12, 2023 at 15:00 comment added coudy Yes, this is the translation used by Cartan. Grating is the term used by Alexander in his 1938 paper and Cartan used the same term in his 1949 course for a slightly more general concept. The definition of carapace given in the linked seminar matches the definition of a grating given in his course.
Jul 12, 2023 at 14:59 history edited LSpice CC BY-SA 4.0
(pre)- -> (pre-); name of seminar; `\cal` -> `\mathcal`
Jul 12, 2023 at 14:58 comment added LSpice Is 'grating' really the standard translation? Google thinks, with no context, that 'carapace' means 'shell', so it seems like 'shelling' might make more sense.
Jul 12, 2023 at 14:28 answer added Simon Wadsley timeline score: 3
Jul 12, 2023 at 9:59 history edited coudy CC BY-SA 4.0
Correct typo
Jul 12, 2023 at 8:25 comment added coudy @NicolasHemelsoet What would be the projection ${\cal F}(U) \mapsto {\cal F}_x$? Also I don't think that point 1 would hold.
Jul 11, 2023 at 18:34 comment added Nicolas Hemelsoet Why not product of $F(U)$ over all $U$?
Jul 11, 2023 at 17:19 history asked coudy CC BY-SA 4.0