Timeline for Do pretopoi have cohomology and homotopy groups?
Current License: CC BY-SA 4.0
8 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Jan 25, 2022 at 16:53 | vote | accept | user475784 | ||
| Jan 25, 2022 at 14:32 | answer | added | Zhen Lin | timeline score: 5 | |
| Jan 25, 2022 at 2:54 | comment | added | Alexander Campbell | It is indeed the case that abelian groups in a pretopos form an abelian category. | |
| Jan 24, 2022 at 22:18 | history | became hot network question | |||
| Jan 24, 2022 at 16:03 | answer | added | Ingo Blechschmidt | timeline score: 13 | |
| Jan 24, 2022 at 15:10 | comment | added | Donu Arapura | I don't know what a pretopos is, but if the axioms are strong enough to prove that the category of abelian groups in it is an abelian category, then you should be able to form Yoneda type $Ext$ groups, so that gives cohomology as $Ext^i(\mathbb{Z}, -)$. | |
| S Jan 24, 2022 at 14:18 | review | First questions | |||
| Jan 24, 2022 at 14:27 | |||||
| S Jan 24, 2022 at 14:18 | history | asked | user475784 | CC BY-SA 4.0 |