3 papers
math.OA2026
Amenable absorption in von Neumann algebras of hyperbolic groups
Juan Felipe Ariza Mejia, Ionut Chifan, Adriana Fernandez Quero +1
We prove that the von Neumann algebra $\cL(G)$ associated with any hyperbolic group satisfies the following \emph{amenable absorption property}: for any infinite maximal amenab…
math.OA2026
Non-amenable C-superrigid groups that are not W-superrigid
Juan Felipe Ariza Mejía, Ionuţ Chifan, Adriana Fernández Quero
Using techniques at the intersection of deformation/rigidity theory, geometric group theory, and the theory of -algebras, we construct a continuum of nonamenable groups th…
math.OA2025
McDuff superrigidity for group II factors
Juan Felipe Ariza Mejía, Ionuţ Chifan, Denis Osin +1
Developing new techniques at the interface of geometric group theory and von Neumann algebras, we identify the first examples of ICC groups whose von Neumann algebras are McDuf…