English

Classification of homomorphisms from $C(\Omega)$ to a $C^*$-algebra

Operator Algebras 2024-08-30 v1

Abstract

Let Ω\Omega be a compact subset of C\mathbb{C} and let AA be a unital simple, separable CC^*-algebra with stable rank one, real rank zero and strict comparison. We show that, given a Cu-morphism α:Cu(C(Ω))Cu(A)\alpha:{\rm Cu}(C(\Omega))\to {\rm Cu}(A) with α(\mathds1Ω)1A\alpha(\langle \mathds{1}_{\Omega}\rangle)\leq \langle 1_A\rangle, there exists a homomorphism ϕ:C(Ω)A\phi: C(\Omega)\to A such that Cu(ϕ)=α{\rm Cu}(\phi)=\alpha and ϕ\phi is unique up to approximate unitary equivalence. We also give classification results for maps from a large class of CC^*-algebras to AA in terms of the Cuntz semigroup.

Cite

@article{arxiv.2408.16657,
  title  = {Classification of homomorphisms from $C(\Omega)$ to a $C^*$-algebra},
  author = {Qingnan An and George Elliott and Zhichao Liu},
  journal= {arXiv preprint arXiv:2408.16657},
  year   = {2024}
}