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arXiv · 2310.15155

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

Dolapo Oyetunbi·Aaron Tikuisis
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Abstract

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

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BibTeXRIS

Dolapo Oyetunbi, Aaron Tikuisis. 2023-10-23. On $\ell$-open $C^*$ algebras and $\ell$-closed $C^*$-algebras. https://arxiv.org/abs/2310.15155

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