Year: 2026
Type: preprint
Abstract: We construct two explicit countable discrete groups $Γ_1$ and $Γ_2$ that are both ICC and have Kazhdan's property (T). Although $Γ_1$ and $Γ_2$ are not isomorphic as groups, their group von Neumann algebras are isomorphic: $L(Γ_1)\cong L(Γ_2)$. This provides a counterexample to Connes' rigidity conjecture for ICC property (T) groups. This result was obtained with assistance from GPT-5.6 Sol, independently of and concurrently with work by OpenAI.
Source: arXiv (Cornell University)
Author: Zhou, Shuoxing
Language: English
Subfield: Mathematical Physics
Field: Mathematics
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7172379511