报告题目 (Title):Measure growth in compact semisimple Lie groups and the Kemperman Inverse Problem
中文标题: 紧半单李群中的测度增长与Kemperman逆问题
报告人 (Speaker):Chieu-Minh Tran(National University of Singapore)
报告时间 (Time):2023年8月7日(周一) 15:00-16:00
报告地点 (Place):校本部 F309
邀请人(Inviter):席东盟、李晋、张德凯
主办部门:永利数学系
报告摘要:Suppose G is a compact semisimple Lie group, μ is the normalized Haar measure on G, and A, A^2⊆G are measurable. We show that μ(A^2)≥min{1,2μ(A)+ημ(A)(1-2μ(A))} with the absolute constant η>0 (independent from the choice of G) quantitatively determined. This is the continuous counterpart of celebrated product theorems by Helfgott, Pyber-Szabo, and Breuillard-Green-Tao. We also show a more general result for abstractly semisimple connected compact groups and resolve the Kemperman Inverse Problem from 1964. (Joint with Jing Yifan).