A GUESS ABOUT POSITIVE APPROXIMATION  

作　　者：李绍宽 

机构地区：[1]China Textile University, Shanghai 200051, PRC

出　　处：《Chinese Science Bulletin》1990年第21期1763-1764,共2页

摘　　要：In [1], P. R. Halmos proposed the following guess: for Hilbert operator A=B+ iC, the inequality(*) holds. Here δ(A) denotes the distance from A to the set of positive operators in the Hilbert space H. And he

关 键 词：POSITIVE OPERATORS numerical RANGE approximate. 

分 类 号：N[自然科学总论]