报告题目：Compact composition operators over Hardy spaces of Dirichlet series

报告人：王茂发 教授（武汉大学）

报告时间：2022年5月16日 周一上午10:00-11:00

报告地点：腾讯会议：390 831 168

报告摘要：Recently, Brevig and Perfekt introduced the mean counting functions for Dirichlet

series and used these to describe all compact composition operators, when the induced symbols

have zero characteristic, on the Hilbert space of Dirichlet series with square summable coefficient,

and left the case of positive characteristics open there. In this talk, we resolve all outstanding

cases. Precisely, we completely characterize the compactness of composition operators induced by

the symbols with positive characteristics on the Hardy spaces of Dirichlet series for general index

including non-Hilbert cases, thus resolving a problem which has been open since the bounded

composition operators were described by Gordon and Hedenmalm. 

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、副院长。主要研究方向是泛函分析及其应用，主持国家自然科学基金项目多项，

在 J. Funct. Anal.、J. Operator Theory、Integr. Equ. Oper. Theory、Math. Z. 等国际著名期刊上发表学术论文70余篇。