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arXiv · 2503.12742

W$^*$-superrigidity for property (T) groups with infinite center

Ionuţ Chifan·Adriana Fernández Quero·Denis Osin·Hui Tan
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Abstract

We propose to study a natural version of Connes' Rigidity Conjecture that involves property (T) groups with infinite center. Utilizing techniques at the intersection of von Neumann algebras and geometric group theory, we establish several cases where this conjecture holds. In particular, we provide the first example of a W$^*$-superrigid property (T) group with infinite center.

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Ionuţ Chifan, Adriana Fernández Quero, Denis Osin, Hui Tan. 2025-03-17. W$^*$-superrigidity for property (T) groups with infinite center. https://arxiv.org/abs/2503.12742

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