Timeline for Flatness of relative canonical bundle
Current License: CC BY-SA 2.5
3 events
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| Mar 16, 2010 at 21:12 | comment | added | BCnrd | Theorem 3.5.1 in my duality book is the reference for a solution to the Exercise 9.7. (When I wrote my original response I wanted to say the CM case is sufficient, but I didn't remember offhand if the flatness of that sheaf over the base also held. So I was lazy and just went with lci, which is certainly somewhat restrictive.) I would guess that assuming just $S_2$ is insufficient, but have no idea on a counterexample. | |
| Mar 16, 2010 at 18:29 | comment | added | Zsolt Patakfalvi | Thanks again, so it seems everything works in the CM case. Now the new question is can we weaken it even more. What about $S_r$. I am specially interested in the $S_2$ case. | |
| Mar 16, 2010 at 17:10 | history | answered | Anatoly Preygel | CC BY-SA 2.5 |