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arXiv · 1506.02950

A note on type I groups acting on d-regular trees

Corina Ciobotaru
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Abstract

In this note, we give new examples of type I groups generalizing a previous result of Ol'shanskii. More precisely, we prove that all closed non-compact subgroups of Aut(T_d) acting transitively on the vertices and on the boundary of a d-regular tree and satisfying Tits' independence property are type I groups. We claim no originality as we use standard ingredients: the polar decomposition of those groups and the admissibility of all their irreducible unitary representations.

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Corina Ciobotaru. 2015-06-09. A note on type I groups acting on d-regular trees. https://arxiv.org/abs/1506.02950

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