Department of Mathematics, Fujian Normal University, Fuzhou, 350007, The People's Republic of China ; Department of Mathematics, Fujian Normal University, Fuzhou, 350007, The People's Republic of China
Abstract:
We prove that for every -hyponormal operator there corresponds a hyponormal operator such that and have ``equal spectral structure". We also prove that every -hyponormal operator is subdecomposable. Then some relevant quasisimilarity results are obtained, including that two quasisimilar -hyponormal operators have equal essential spectra.