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arXiv · 1311.4513

Character rigidity for lattices and commensurators

Darren Creutz·Jesse Peterson
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Abstract

We prove an operator algebraic superrigidity statement for homomorphisms of irreducible lattices, and also their commensurators, in certain higher-rank groups into unitary groups of finite factors. This extends the authors' previous work regarding non-free measure-preserving actions, and also answers a question of Connes for such groups.

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Darren Creutz, Jesse Peterson. 2013-11-18. Character rigidity for lattices and commensurators. https://arxiv.org/abs/1311.4513

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