Timeline for Equivalent functors
Current License: CC BY-SA 3.0
4 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Sep 4, 2011 at 0:33 | vote | accept | minhtringuyen | ||
| Sep 2, 2011 at 17:17 | comment | added | Donu Arapura | You can define $Ext$ by taking derived functors of $Hom$ in either variable. If you are using the second variable, it's tautologically true (see Andreas Blass' answer). So I suspect you might be defining it via a projective resolution of $M$ (or via Yoneda or...) Then there is something to prove, but this can be found in many homological algebra texts. I'm sure someone can elaborate, but it would be good to clarify this. | |
| Sep 2, 2011 at 16:48 | answer | added | Andreas Blass | timeline score: 1 | |
| Sep 2, 2011 at 16:01 | history | asked | minhtringuyen | CC BY-SA 3.0 |