Timeline for Divisor class group of quartic surfaces
Current License: CC BY-SA 3.0
3 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Mar 7, 2022 at 22:11 | vote | accept | CommunityBot | ||
| Mar 3, 2017 at 17:11 | comment | added | Mohan | @gbp No, you can not have a triple point. Consider the projection from the triple point, which gives a birational map to the plane. If $\Gamma$ is its graph, then, using the hypothesis, you can show that the projection to the plane from $\Gamma$ is an isomorphism, by showing that the map must be quasi-finite (since any curve contracted must be a line in the quartic, and there are no lines in the quartic) and then appealing to Zariski's Main Theorem . Then you have a birational morphism from the plane to the quartic, which is absurd. I do not know tacnodes which are UFDs, but not sure. | |
| Mar 2, 2017 at 1:13 | history | answered | Mohan | CC BY-SA 3.0 |