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RADU GROUPS ACTING ON TREES ARE CCR
Part of:
Structure and classification of infinite or finite groups
Locally compact groups and their algebras
Low-dimensional topology
Published online by Cambridge University Press: 06 March 2024
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.
Keywords
MSC classification
- Type
- Research Article
- Information
- Copyright
- © The Author(s), 2024. Published by Cambridge University Press on behalf of Australian Mathematical Publishing Association Inc.
Footnotes
Communicated by George Willis
The author is an F.R.S.-FNRS Research Fellow.
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