Grüss type inequalities for positive linear maps on $C^{\ast }$-algebras

Ali Dadkhah, Mohammad Sal Moslehian

Let $\mathcal{A}$ and $\mathcal{B}$ be two unital $C^{\ast }$-algebras and let for $C\in \mathcal{A},{\Gamma }_C=\{\gamma \in \mathbb{C}:\Vert C-\gamma I\Vert ={\inf }_{\alpha \in \mathbb{C}}\Vert C-\alpha I\Vert \}$. We prove that i…