154.com皇冠学术报告

The subset selection and the partition problem for high rank positive semidefinite matrices

徐孜立

（香港科技大学）

报告时间：2022年9月9日，星期五，下午4:00-5:00

报告地点：腾讯会议：756-827-410  会议密码：1123

报告摘要：Recently Marcus-Spielman-Srivastava proved Weaver’s KS conjecture, which gives a positive solution to the Kadison-Singer problem.  Cohen and Branden independently extended this result to obtain the arbitrary-rank version of Weaver’s KS conjecture. In this talk, we present a new bound in Weaver’s KS conjecture for the arbitrary-rank case. To do that, we introduce the definition of (k,m)-characteristic polynomials and employ it to improve the previous estimate on the largest root of the mixed characteristic polynomials. We also introduce our recent work on the subset selection problem for high rank positive semidefinite matrices.

报告人简介：徐孜立，博士毕业于中科院数学与系统科学研究院，导师许志强研究员。目前在香港科技大学做博士后，合作导师蔡剑锋教授。研究方向为框架理论、势能极小化问题、球面设计、矩阵子集选择问题等。目前在国际著名期刊如Appl. Comput. Hamon. Anal. 等发表论文多篇。

邀请人： 黄猛