报告题目： On Hausdorff dimension of the set of nonergodic directions 报 告 人： 黄炎 报告人所在单位： 河南大学 报告日期： 2020-09-06 星期日 报告时间： 10:00-11:00 报告地点： 腾讯会议ID: 656 940 706 报告摘要： In this talk, we show a recent progress about Hausdorff dimension of the set of nonergodic directions. Let X be the resulting surface by gluing two copies of the flat torus along a segment with holonomy vector (lambda,mu) and let q_k be the sequence of best simultaneous approximation denominators to (lambda,mu)，related to any norm of R^2. If q_{k+1}=O(q_k^N) for some N>0, then the set of nonergodic directions in X has Hausdorff dimension 1/2; if \sum(loglogq_{k+1})/q_k=infty, then the dimension is 0. This was a joint work with Yitwah Cheung. 本年度学院报告总序号： 136