Algebraic orthogonality in $C^{\ast }$--algebras-II

Anil Kumar Karn

We prove the following: Let $A$ be a C${}^{\ast }$-algebra. Then for $a,b\in A^{+}\setminus \{0\}$, we have $ab=0$ if and only is $\Vert \Vert c \Vert^{-1} c + \Vert d \Vert^{-1}…