算子理论与算子代数及其应用报告会

报告题目：Linear combinations of composition operators on a Hilbert space of Dirichlet series

报告人：王茂发  教授 （武汉大学）

报告时间：2022年5月27日 （星期五）下午14：00-15：00

腾讯会议：392-288-808

邀请人：杨义新 教授

报告摘要：The aim of this talk is to characterize when linear combinations of composition operators are compact on the Hilbert space of Dirichlet series with square summable coefficients. Especially, we discuss the topological structure of the set of composition operators acting on the Hilbert space of Dirichlet series. It reveals that there exists a continuous arc in the set of all bounded composition operators on the space containing non-compact ones. Moreover, it is shown that the linear combinations of composition operators induced by finitely many distinct linear symbols are compact only when each one of them is compact. This is a joint work with Frederic Bayart and Xingxing Yao.

报告人简介：王茂发，武汉大学数学与统计学院教授、博士生导师。主要研究方向是泛函分析及其应用，特别是在函数空间上的算子理论方面取得了系列原创性成果。多次承担863项目、国家基金委重点项目、面上项目和教育部项目等，已在Sci. China Math., J. Funct. Anal., J. Operator Theory, Indiana Uni. J. Math.等国际知名期刊上发表SCI学术论文70余篇。