Jambura Journal of Mathematics
Vol 8, No 2: August 2025

On Deformed-Metric Equivalence of Hilbert Space Operators

Amenya Collins (Maasai Mara University)
Victor Wanjala (Maasai Mara University)
John Matuya (Maasai Mara University)



Article Info

Publish Date
20 Jul 2026

Abstract

This paper introduces and studies a novel class of equivalence relations in operator theory, called deformed-metrically equivalent operators. Two operators S and T in B(H) are said to be deformed-metrically equivalent if there exists a positive operator P such that SPS = TT. This definition generalizes traditional metric equivalence by incorporating a positive deformation operator P, enabling a richer algebraic and spectral analysis. We establish several fundamental results, including the preservation of key operator classes such as normality, posinormality, and compactness under suitable commutativity conditions. Spectral inclusion relations are derived under invertibility assumptions, and the equivalence is shown to be stable under limits, tensor products, and functional calculus. Moreover, the set of all operators deformed-metrically equivalent to a given operator forms an affine space that is closed in the weak operator topology. These findings deepen the theoretical framework of operator equivalence and reveal new connections with well-studied classes such as posinormal, supraposinormal, and k-quasi n-power posinormal operators.

Copyrights © 2025






Journal Info

Abbrev

jjom

Publisher

Subject

Mathematics

Description

Jambura Journal of Mathematics (JJoM) is a peer-reviewed journal published by Department of Mathematics, State University of Gorontalo. This journal is available in print and online and highly respects the publication ethic and avoids any type of plagiarism. JJoM is intended as a communication forum ...