On Automatic Continuity of 3-Homomorphisms on Banach Algebras Bracic, Jankoauthor Moslehian, Mohammad SalauthorA linear map $\varphi : \mathcal{A} \rightarrow \mathcal{B}$ between (Banach) algebras is called 3- homomorphism if $\varphi (abc) = \varphi (a)\varphi (b)\varphi (c)$ for each $a, b, c \in \mathcal{A}$. We investigate 3-homomorphisms on Banach algebras with bounded approximate identities and establish in two ways (for unital and non-unital cases) that every involution preserving homomorphism between $C^\ast$-algebras is norm decreasing. Q Science, Computer Science2007Penerbit Universiti Sains MalaysiaJournal