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arXiv · 0906.4916

The full group C*-algebra of the modular group is primitive

Erik Bedos·Tron Omland
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Abstract

We show that the full group C$^*$-algebra of $PSL(n, \Z)$ is primitive when $n=2$, and not primitive when $n\geq 3$. Moreover, we show that there exists an uncountable family of pairwise inequivalent, faithful irreducible representations of $C^*(PSL(2,\Z))$.

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Erik Bedos, Tron Omland. 2009-06-26. The full group C*-algebra of the modular group is primitive. https://arxiv.org/abs/0906.4916

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