A characterization of semiprojectivity for commutative C*‐algebras

  title={A characterization of semiprojectivity for commutative C*‐algebras},
  author={Adam P. W. S{\o}rensen and Hannes Thiel},
  journal={Proceedings of the London Mathematical Society},
Given a compact metric space X, we show that the commutative C*‐algebra C(X) is semiprojective if and only if X is an absolute neighbourhood retract of dimension at most 1. This confirms a conjecture of Blackadar. 
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