报告人：王俭（南开大学）

时间：2021年10月12日10:00开始

腾讯会议ID：723 955 328

摘要：In this talk,  we show that under certain boundedness condition, a $C^r$  conservative irrational pseudo-rotations on $\mathbb{T}^2$ with a generic rotation vector  is $C^{r-1}$-rigid. We also obtain $C^0$-rigidity for H\"older pseudo-rotations with similar properties. These provide a partial generalisation of the main results in [B. Bramham, Invent. Math. (2015), no. 2, 561-580; A. Avila, B. Fayad, P. Le Calvez, D. Xu and Z. Zhang,  Invent. Math. (2020), no. 3, 673–714]. Furthermore, we construct a $C^\omega$ conservative (resp. minimal)  totally irrational pseudo-rotation with a super-Liouvillean vector and bounded mean motion that is not conjugate to an irrational rotation by the classical Anosov-Katok method.  Combining with a theorem of J\"ager, we give a negative answer to a question of A. Norton and D. Sullivan in the $C^\omega$ category. This is joint work with Zhiyuan Zhang and Hui Yang respectively.

简介:王俭，南开大学数学学院副教授。博士毕业于清华大学&巴黎第十三大学，曾在南开大学陈省身数学研究所、德国马普所、巴西IMPA做博士后，2020年入选南开大学百名青年学科带头人培养计划。主要从事曲面动力系统以及辛动力系统的研究，目前在GAFA，Adv in Math, TAMS, AIHP C, IMRN 等国际知名数学期刊发表论文多篇。

邀请人：罗军

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