Complementary and refined inequalities of Callebaut inequality for operators

M. Bakherad, M. S. Moslehian

The Callebaut inequality says that \begin{align*} \sum_{ j=1}^n \left(A_j\sharp B_j\right)\leq \left(\sum_{ j=1}^n A_j σB_j\right)\sharp\left(\sum_{ j=1}^n A_j σ^{\bot} B_j\right)\…