報告題目：Spectral gap in subgroups of SL_d(Z/nZ)
報告人：何偉鯤（中國科必一數學研究所）
報告時間：2023年10月19日14:00
報告地點：線上騰訊會議：791-486-685
報告摘要：Uniform spectral gap (of the discrete Laplace operators) of a family of finite groups is also known as expansion in groups or property (tau). In the case of SL_2(Z/nZ), a uniform spectral gap is present as a consequence of Selberg's 3/16 theorem and the Burger-Brooks correspondence. In this talk, I will explain how to show uniform spectral gap in broader classes of groups, using combinatorics and dynamics. This talk is based on a joint work with Nicolas de Saxce, which is build on works of Bourgain-Gamburd and Bourgain-Varju among others.
報告人簡介：何偉鯤，2017年在法國巴黎薩克雷大學取得博士學位，隨後在以色列希伯來大學和韓國高等研究院做博士後，現為中國科必一數學與系統科學研究院副研究員。研究領域為遍歷論與分形幾何。