New holomorphically closed subalgebras of $C^*$-algebras of hyperbolic groups

Michael Puschnigg

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arXiv · 0904.3675

New holomorphically closed subalgebras of $C^*$-algebras of hyperbolic groups

Michael Puschnigg

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Abstract

We construct dense, unconditional subalgebras of the reduced group $C^*$-algebra of a word-hyperbolic group, which are closed under holomorphic functional calculus and possess many bounded traces. Applications to the cyclic cohomology of group $C^*$-algebras and to delocalized $L^2$-invariants of negatively curved manifolds are given.

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Michael Puschnigg. 2009-04-23. New holomorphically closed subalgebras of $C^*$-algebras of hyperbolic groups. https://arxiv.org/abs/0904.3675

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