Timeline for Nefness on a K3 surface
Current License: CC BY-SA 3.0
4 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Nov 12, 2013 at 17:54 | comment | added | Abhinav Kumar | Not if the divisor $D$ is reducible - else take $D = C + f$ on a Hirzebruch surface with $C^2 = -2, f^2 = 0, C \cdot f = 1$, and notice $D \cdot C = -1$. If you don't assume $D$ is effective, then Jason's comment shows you that there's no way to distinguish $D$ from its negative. | |
| Nov 12, 2013 at 17:15 | comment | added | Heitor | Wait a moment. But if $D$ is effective and $D^2\geq 0$ then $D$ is nef on any surface, isn't it? | |
| Nov 12, 2013 at 17:08 | vote | accept | Heitor | ||
| Nov 12, 2013 at 17:12 | |||||
| Nov 12, 2013 at 14:12 | history | answered | Abhinav Kumar | CC BY-SA 3.0 |