English

On $\ell$-open $C^*$ algebras and $\ell$-closed $C^*$-algebras

Operator Algebras 2024-01-31 v2

Abstract

In this paper, we characterize \ell-open and \ell-closed CC^*-algebras and deduce that \ell-open CC^*-algebras are \ell-closed, as conjectured by Blackadar. Moreover, we show that a commutative unital CC^*-algebra is \ell-open if and only if it is semiprojective.

Keywords

Cite

@article{arxiv.2310.15155,
  title  = {On $\ell$-open $C^*$ algebras and $\ell$-closed $C^*$-algebras},
  author = {Dolapo Oyetunbi and Aaron Tikuisis},
  journal= {arXiv preprint arXiv:2310.15155},
  year   = {2024}
}

Comments

Minor changes. Added Remark 4.4 and Proposition 5.3