首页 | 本学科首页   官方微博 | 高级检索  
     检索      


Path connectivity of idempotents on a Hilbert space
Authors:Yan-Ni Chen  Hong-Ke Du  Hai-Yan Zhang
Institution:Department of Mathematics, Shaanxi University of Technology, Hanzhong 723001, People's Republic of China ; College of Mathematics and Information Science, Shaanxi Normal University, Xi'an 710062, People's Republic of China ; College of Mathematics and Information Science, Shaanxi Normal University, Xi'an 710062, People's Republic of China
Abstract:Let $ P$ and $ Q$ be two idempotents on a Hilbert space. In 2005, J. Giol in Segments of bounded linear idempotents on a Hilbert space, J. Funct. Anal. 229(2005) 405-423] had established that, if $ P+Q-I$ is invertible, then $ P$ and $ Q$ are homotopic with $ \tilde{s}(P,Q)\leq 2.$ In this paper, we have given a necessary and sufficient condition that $ \tilde{s}(P,Q)\leq 2,$ where $ \tilde{s}(P,Q)$ denotes the minimal number of segments required to connect not only from $ P$ to $ Q$, but also from $ Q$ to $ P$ in the set of idempotents.

Keywords:Idempotent  orthogonal projection  homotopic  path connectivity
点击此处可从《Proceedings of the American Mathematical Society》浏览原始摘要信息
点击此处可从《Proceedings of the American Mathematical Society》下载免费的PDF全文
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号