On the character space of Banach vector-valued function algebras

Abstract

Given a compact space $X$ and a commutative Banach algebra $A$, the character spaces of $A$-valued function algebras on $X$ are investigated. The class of natural $A$-valued function algebras, those whose characters can be described by means of characters of $A$ and point evaluation homomorphisms, is introduced and studied. For an admissible Banach $A$-valued function algebra $\mathcal{A}$ on $X$, conditions under which the character space $M(\mathcal{A})$ is homeomorphic to $M(\mathfrak{A})\times M(A)$ are presented, where $\mathfrak{A}=C(X)\cap \mathcal{A}$ is the subalgebra of $\mathcal{A}$ consisting of scalar-valued functions. An illustration of the results is given by some examples.

to appear in Bull. Iranian Math. Soc