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Topological entropy of some automorphisms of reduced amalgamated free product C*-algebras

Ken Dykema
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Abstract

Certain classes of automorphisms of recued amalgamated free products of C*-algebras are shown to have Brown-Voiculescu topological entropy zero. Also, for automorphisms of exact C*-algebras, the Connes-Narnhofer-Thirring entropy is shown to be bounded above by the Brown-Voiculescu entropy. These facts are applied to generalize Stormer's result about entropy of automorphisms of the II_1-factor of a free group.

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Ken Dykema. 1999-11-02. Topological entropy of some automorphisms of reduced amalgamated free product C*-algebras. https://arxiv.org/abs/math/9911010

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