DOI: 10.3390/axioms15100719 ISSN: 2075-1680

Operator Sum Inequalities in the A-Normalized Berezin Framework

Maryam G. Alshehri, Kais Feki

Building on recent approaches to generalized Berezin norms by by Albeladi, Feki, and Taha, this paper establishes several refined upper bounds for the A-normalized Berezin number and its associated seminorms for finite operator sums in reproducing kernel spaces, where A is a non-zero positive semidefinite operator inducing the semi-Hilbertian structure. By systematically leveraging the A-Cartesian decomposition alongside generalizations of the Dragomir, Buzano, and McCarthy inequalities, we deduce robust higher-power estimates that rectify and extend the existing literature. Furthermore, we derive an integral bound that refines the standard triangle inequality for the A-normalized Berezin operator radius, and establish a characterization of equality.