Timeline for Is there a notion of Čech groupoid of a cover of an object in a Grothendieck site?
Current License: CC BY-SA 4.0
6 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Oct 17, 2020 at 10:39 | history | became hot network question | |||
| Oct 17, 2020 at 6:13 | vote | accept | Adittya Chaudhuri | ||
| Oct 17, 2020 at 4:37 | answer | added | Dmitri Pavlov | timeline score: 9 | |
| Oct 17, 2020 at 2:55 | comment | added | Adittya Chaudhuri | @ZhenLin No, I am not assuming that pull-backs or disjoint unions to exist . I actually just need the existence of a pretopology on a category $C$ in the sense of definition 2.24 in page 27 of homepage.sns.it/vistoli/descent.pdf. I was thinking about the functors from "such Čech groupoids" (if there is) to $BG$, the delooping of a group. I was thinking whether one can define the notion of locally trivial principal bundles over an object of a site. (I know that Grothendieck topology was introduced for different purpose but I am just curious). Apology in advance if I sound stupid. | |
| Oct 17, 2020 at 2:40 | comment | added | Zhen Lin | What kind of site? (Does it have pullbacks? Disjoint unions?) What do you hope to do with the “groupoid” you get? | |
| Oct 17, 2020 at 2:32 | history | asked | Adittya Chaudhuri | CC BY-SA 4.0 |