[geometry-ml:04887] 東工大幾何セミナー (10/21)

[Nobuhiro Honda]

幾何学メーリングリストの皆様

東工大幾何セミナーのお知らせです。
対面、Zoomのハイブリッド形式で行う予定です。
ZoomURLは講演開始前までに
http://www.math.titech.ac.jp/~honda/index.html
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10月21日(金) 16:30-18:00 
大岡山キャンパス本館2階 H224Bセミナー室
講演者　服部真史氏（京大理）
「On K-stabilty of algebraic fiber spaces」

Abstract: In K-stability, the characterization of K-stable varieties is well-studied when $K_X$ is ample or $X$ is a Calabi-Yau or Fano variety. The cscK problem of smooth fibrations was also studied by Fine and Dervan-Sektnan. Nevertheless, K-stability of a fibration with a singular fiber is not known much. We introduce adiabatic K-stability (If $f:(X,H)\to (B,L)$ is a fibration of polarized varieties, this means that K-stability of $(X,aH+L)$ for sufficiently small $a$) and show that adiabatic K-semistability of Calabi-Yau fibration (i.e., $K_X$ is relatively trivial) implies log-twisted K-semistability of the base variety by applying the canonical bundle formula. If the base is a curve, we also obtain a partial converse. In this talk, I would like to explain a sufficient condition for the existence of cscK metrics on rational elliptic surfaces as an application of our main result. In addition, I would like to explain our result on K-stability of relatively K-ample fibered surfaces.

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セミナー室の場所については
http://www.math.titech.ac.jp/map.pdf
をご覧下さい。

今後のセミナーの予定については以下をご覧ください。
http://www.math.titech.ac.jp/~honda/index.html

皆様のご参加をお待ちしております。

本多宣博
東京工業大学理学院数学系