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arXiv · 2607.29571

Strongly converging unitary representations for extensions by exact groups

David Gao·Srivatsav Kunnawalkam Elayavalli·Mahan Mj
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Abstract

We prove the existence of strongly converging unitary representations in various new settings of countable groups, in particular, arising as extensions by exact groups: semidirect products with amenable groups; generalized wreath products with abelian base; graph wreath products; various free-by-cyclic groups including Gersten's group; and general Bernoulli shift crossed products on $C^*$-algebras.

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David Gao, Srivatsav Kunnawalkam Elayavalli, Mahan Mj. 2026-07-31. Strongly converging unitary representations for extensions by exact groups. https://arxiv.org/abs/2607.29571

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