Free group $C^*$-algebras associated with $\ell_p$

Rui Okayasu

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arXiv · 1203.0800

Free group $C^*$-algebras associated with $\ell_p$

Rui Okayasu

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Abstract

For every $p\geq 2$, we give a characterization of positive definite functions on a free group with finitely many generators, which can be extended to the positive linear functionals on the free group $C^*$-algebra associated with the ideal $\ell_p$. This is a generalization of Haagerup's characterization for the case of the reduced free group $C^*$-algebra. As a consequence, the associated $C^*$-algebras are mutually non-isomorphic, and they have a unique tracial state.

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BibTeX RIS

Rui Okayasu. 2012-03-05. Free group $C^*$-algebras associated with $\ell_p$. https://arxiv.org/abs/1203.0800

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