Subalgebras of finite codimension in semiprojective 𝐶*-algebras

Enders, Dominic

doi:10.1090/proc/13620

Subalgebras of finite codimension in semiprojective $C^*$-algebras
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Proc. Amer. Math. Soc. 145 (2017), 4795-4805 Request permission

Abstract:

We show that semiprojectivity of a $C^*$-algebra is preserved when passing to $C^*$-subalgebras of finite codimension. In particular, any pullback of two semiprojective $C^*$-algebras over a finite-dimensional $C^*$-algebra is again semiprojective.

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