Characterization of operator convex functions by certain operator inequalities
Characterization of operator convex functions by certain operator inequalities
For λ ∈ (0,1) , let ψ be a non-constant, non-negative, continuous function on (0,∞) and let Γ λ (ψ) be the set of all non-trivial operator means σ such that an inequalityholds for all A,B ∈ B(H) ++ .Then we have:1. ψ is a decreasing operator convex function if …