代数幾何学セミナー

過去の記録 ~09/28次回の予定今後の予定 09/29~

開催情報 火曜日 15:30~17:00 数理科学研究科棟(駒場) 122号室
担当者 權業 善範・中村 勇哉・田中公

2015年05月25日(月)

15:30-17:00   数理科学研究科棟(駒場) 122号室
松本雄也 氏 (東大数理)
Good reduction of K3 surfaces (日本語 or English)
[ 講演概要 ]
We consider degeneration of K3 surfaces over a 1-dimensional base scheme
of mixed characteristic (e.g. Spec of the p-adic integers).
Under the assumption of potential semistable reduction, we first prove
that a trivial monodromy action on the l-adic etale cohomology group
implies potential good reduction, where potential means that we allow a
finite base extension.
Moreover we show that a finite etale base change suffices.
The proof for the first part involves a mixed characteristic
3-dimensional MMP (Kawamata) and the classification of semistable
degeneration of K3 surfaces (Kulikov, Persson--Pinkham, Nakkajima).
For the second part, we consider flops and descent arguments. This is a joint work with Christian Liedtke.
[ 参考URL ]
https://www.ms.u-tokyo.ac.jp/~ymatsu/index_j.html