Abstract
We have presented recently an example of a C*-extension, which is not invertible in the semigroup of homotopy classes of C*-extensions. Here we reveal the cause for existence of homotopy non-invertible C*-extensions: it is related to non-exact C*-algebras and to possibility to distinguish different tensor C*-norms by K-theory. We construct a special C*-algebra, K-theory of which hosts an obstruction for homotopical non-invertibility, and show that this obstruction for our example does not vanish.
Research was partially supported by RFFI grant 05-01-00923.
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Manuilov, V. (2008). On Homotopical Non-invertibility of C*-extensions. In: Bastos, M.A., Lebre, A.B., Speck, FO., Gohberg, I. (eds) Operator Algebras, Operator Theory and Applications. Operator Theory: Advances and Applications, vol 181. Birkhäuser Basel. https://doi.org/10.1007/978-3-7643-8684-9_14
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DOI: https://doi.org/10.1007/978-3-7643-8684-9_14
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