On a-self-adjoint, a-unitary opeators and quasiaffinities

Abstract

In this paper, we investigate properties of A-self adjoint operators and other relations on Hilbert spaces. In this context, A is a self-adjoint and an invertible operator. More results on operator equivalences including similarity, unitary and metric equivalences are discussed. We also investigate conditions under which these classes of operators are self- adjoint and unitary. We finally locate their spectra.