## Subalgebras of finite codimension in semiprojective $C^*$-algebras

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- by Dominic Enders
- Proc. Amer. Math. Soc.
**145**(2017), 4795-4805 - DOI: https://doi.org/10.1090/proc/13620
- Published electronically: May 26, 2017
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## 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.## References

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## Bibliographic Information

**Dominic Enders**- Affiliation: Westfälische Wilhelms-Universität, Fachbereich Mathematik, Einsteinstrasse 62, 48149 Münster, Germany
- MR Author ID: 1101375
- Email: d.enders@uni-muenster.de
- Received by editor(s): July 20, 2016
- Received by editor(s) in revised form: December 5, 2016
- Published electronically: May 26, 2017
- Additional Notes: This work was supported by the SFB 878
*Groups, Geometry and Actions*and the Danish National Research Foundation through the Centre for Symmetry and Deformation (DNRF92) - Communicated by: Adrian Ioana
- © Copyright 2017 American Mathematical Society
- Journal: Proc. Amer. Math. Soc.
**145**(2017), 4795-4805 - MSC (2010): Primary 46L05
- DOI: https://doi.org/10.1090/proc/13620
- MathSciNet review: 3691996