Algebraic Geometry Seminar

Seminar information archive ~05/01Next seminarFuture seminars 05/02~

Date, time & place Friday 13:30 - 15:00 118Room #118 (Graduate School of Math. Sci. Bldg.)
Organizer(s) GONGYO Yoshinori, KAWAKAMI Tatsuro, ENOKIZONO Makoto

2007/05/07

16:30-18:00   Room #122 (Graduate School of Math. Sci. Bldg.)
謝啓鴻(Xie Qihong) (東大・数理)
Pathologies on ruled surfaces in positive characteristic
[ Abstract ]
We discuss some pathologies of log varieties in positive characteristic. Mainly, we show that on ruled surfaces there are counterexamples of several logarithmic type theorems. On the other hand, we also give a characterization of the counterexamples of the Kawamata-Viehweg vanishing theorem on a geometrically ruled surface by means of the Tango invariant of the base curve.