On Approximation Properties of Pimsner Algebras and Crossed Products by Hilbert Bimodules
نویسنده
چکیده
Let X be a Hilbert bimodule over a C-algebra A and OX = A ⋊X Z. Using a finite section method we construct a sequence of completely positive contractions factoring through matrix algebras over A which act on sξs ∗ η as Schur multipliers converging to the identity. This shows immediately that for a finitely generated X the algebra OX inherits any standard approximation property such as nuclearity, exactness, CBAP or OAP from A. We generalise this to certain general Pimsner algebras by proving semi-splitness of the Toeplitz extension under certain conditions and discuss some examples.
منابع مشابه
A Note on Approximation Properties of Crossed Products by Hilbert Bimodules
Let X be a Hilbert bimodule over a C∗-algebra A and OX = A⋊X Z. Using a finite section method we construct a sequence of completely positive contractions factoring through matrix algebras over A which act on sξs ∗ η as Schur multipliers converging to the identity. This shows immediately that for a finitely generated X the algebra OX inherits any standard approximation property such as nuclearit...
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