Let $A$ and $B$ be $C^{\ast}-$Algebras. Assume that $A \otimes B$ denotes the minimal (spatial) tensor product. Is it true that $Z(A \otimes B)= Z(A) \otimes Z(B)$ where $Z$ is used for center.
Note that $Z(A) \otimes Z(B)\subset Z(A \otimes B)$. Also as $Z(A) \otimes Z(B)$ is $*$-subalgebra Of $A \otimes B$ so using injectivity of min the identity map extends uniquely to an $*$-isometric map say $\theta: Z(A)\otimes Z(B) \to Z(A\otimes B)$. We only need to show $\theta$ is surjective. Any ideas?