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
8RUAN Yingbin Department of Mathematics, Fujian Normal University, Fuzhou 350007, China,Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100080, China.Relations between Lipschitz functions and convex functions[J].Science China Mathematics,2005,48(5):703-710. 被引量：1
