Title：Collapsing geometry of hyperkaehler four-manifolds

Abstract：This talk focuses on the recent resolution of two well-known conjectures in the study of Ricci-flat four manifolds (joint with Song Sun).

(1) Any volume collapsed limit of unit-diameter hyperkaehler metrics on the K3 manifold is isometric to one of the following: the quotient of a flat 3-torus by an involution, a singular special Kaehler metric on the 2-sphere, or the unit interval.

(2) Any complete non-compact hyperkaehler 4-manifold with quadratically integrable curvature must have one of the following asymptotic model geometries: ALE, ALF, ALG, ALH, ALG* and ALH*.

With the above classification results, we obtain a rather complete picture of the collapsing geometry of hyperkaehler four manifolds.

报告人：张若冰，普林斯顿大学 （研究方向：微分几何和偏微分方程）

报告时间：2021年11月4日（星期四）上午10:00-11:00

报告方式：腾讯会议，会议ID：499 879 763

https://meeting.tencent.com/dm/ZFUSkTNpHTSQ

邀请人：李刚