On Unitary Quasi-equivalence and Partial Isometry Operators in Hilbert Spaces

Unitary quasi-equivalence has been shown to be an equivalence relation. Similarly, unitary quasi-equivalence has been proven to preserve normality, hyponormality and binormality of operators. However, the properties of unitary quasi-equivalence and partial isometric operators have not been established. In this paper therefore, the study aims to determine the properties of unitary quasi-equivalence and isometry, co-isometry and partial isometry operators.