Homomorphisms from AH-algebras

Let $C$ be a general unital AH-algebra and let $A$ be a unital simple $C^*$-algebra with tracial rank at most one. Suppose that $ϕ, ψ: C\to A$ are two unital monomorphisms. We show that $ϕ$ and $ψ$ are approximately unitarily equivalent if and only if \beq[ϕ]&=&[ψ] {\rm in} KL(C,A), ϕ_{\sharp}&=&ψ_{\sharp}\tand ϕ^†&=&ψ^†, \eneq where $ϕ_{\sharp}$ and $ψ_{\sharp}$ are continuous affine maps from tracial state space $T(A)$ of $A$ to faithful tracial state space $T_{\rm f}(C)$ of $C$ induced by $ϕ$ and $ψ,$ respectively, and $ϕ^‡$ and $ψ^‡$ are induced homomorphisms from $K_1(C)$ into $\Aff(T(A))/\bar{ρ_A(K_0(A))},$ where $\Aff(T(A))$ is the space of all real affine continuous functions on $T(A)$ and $\bar{ρ_A(K_0(A))}$ is the closure of the image of $K_0(A)$ in the affine space $\Aff(T(A)).$ In particular, the above holds for $C=C(X),$ the algebra of continuous functions on a compact metric space. An approximate version of this is also obtained. We also show that, given a triple of compatible elements $κ\in KL_e(C,A)^{++},$ an affine map $γ: T(C)\to T_{\rm f}(C)$ and a \hm $\af: K_1(C)\to \Aff(T(A))/\bar{ρ_A(K_0(A))},$ there exists a unital monomorphism $ϕ: C\to A$ such that $[h]=κ,$ $h_{\sharp}=γ$ and $ϕ^†=\af.$

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