Timeline for Tor-amplitude [0, 1] in the setting of intersection theory on a regular surface?
Current License: CC BY-SA 3.0
6 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Aug 2, 2015 at 15:19 | vote | accept | O-Ren Ishii | ||
| Aug 1, 2015 at 22:32 | answer | added | Jason Starr | timeline score: 3 | |
| Aug 1, 2015 at 19:58 | comment | added | O-Ren Ishii | @JasonStarr: Thank you! I had a feeling that I was missing something basic. | |
| Aug 1, 2015 at 19:17 | comment | added | Jason Starr | Regarding your second question about the relationship between tor-amplitude and dimension of the support of a sheaf, one such result is the New Intersection Theorem. | |
| Aug 1, 2015 at 18:47 | comment | added | Jason Starr | On a regular scheme, effective Weil divisors are Cartier divisors, i.e., the ideal sheaf $\mathcal{I}_D$ is an invertible $\mathcal{O}_X$-module. Thus the complex supported in degrees $[-1,0]$, $\mathcal{I}_D\hookrightarrow \mathcal{O}_X$, is quasi-isomorphic to $\mathcal{O}_D$ (in degree $0$) as a complex of $\mathcal{O}_X$-modules. Thus the tor-amplitude is $[0,1]$. | |
| Aug 1, 2015 at 17:53 | history | asked | O-Ren Ishii | CC BY-SA 3.0 |