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arXiv · 2203.04189

Radu groups acting on trees are CCR

Lancelot Semal
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Abstract

We classify the irreducible unitary representations of closed simple groups of automorphisms of trees acting $2$-transitively on the boundary and whose local action at every vertex contains the alternating group. As an application, we confirm Claudio Nebbia's CCR conjecture on trees for $(d_0,d_1)$-semi-regular trees such that $d_0,d_1\in \Theta$, where $\Theta$ is an asymptotically dense set of positive integers.

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Lancelot Semal. 2022-03-08. Radu groups acting on trees are CCR. https://doi.org/10.1017/s1446788723000381

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