Mathematische Annalen

, Volume 342, Issue 2, pp 273–277 | Cite as

All extensions of \({C^*_r\left(\mathbb F_n\right)}\) are semi-invertible

  • Klaus ThomsenEmail author


It is shown that an extension of the reduced group C *-algebra of a free group by the compact operators can be made asymptotically split by addition of another extension which admits a completely positive lifting.

Mathematics Subject Classification (2000)



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Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  1. 1.Institut for matematiske fagAarhus CDenmark

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