报告题目: Product of operators and the product of their numerical ranges

报告人：Chi-Kwong Li（College of William and Mary）

时间：2014年7月21日（星期一）15:00-16:00

地点：理科楼数学系A304

摘要：We show that a compact operator A is a multiple of a positive operator if and only if the spectrum of AB is always a subset of the closure of the product of the numerical ranges W(A) and W(B) for any (rank one) operator B. The sufficiency may fail for a general operator A. Other classes of operators for the equivalence conditions to hold are identified, and related problems are discussed.

联系人：崔健莲