Abstract
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.
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Thomsen, K. All extensions of \({C^*_r\left(\mathbb F_n\right)}\) are semi-invertible. Math. Ann. 342, 273–277 (2008). https://doi.org/10.1007/s00208-008-0232-5
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DOI: https://doi.org/10.1007/s00208-008-0232-5