Opuscula Math.
27
, no. 1
(), 73-81
Opuscula Mathematica

# On quasi-similarity and ω-hyponormal operators

Abstract. In this paper, it is shown that a Putnam-Fuglede type commutativity theorem holds for $$\omega$$-hyponormal operators, the normal parts of quasi-similar $$\omega$$-hyponormal operators are unitarily equivalent and a $$\omega$$-hyponormal spectral operator is normal.
Keywords: $$\omega$$-hyponormal operators, quasi-similarity.
Mathematics Subject Classification: 47B20.