Sorin Popa

most citedOn co-amenability for groups and von Neumann algebras

21 citations · 21 across the 2 of their papers we have counts for

collaborators

3 papers

math.OA2023

Non-isomorphism of $A^{* n}, 2 \leq n \leq \infty$ , for a non-separable abelian von Neumann algebra $A$

Rémi Boutonnet, Daniel Drimbe, Adrian Ioana +1

We prove that if $A$ is a non-separable abelian tracial von Neuman algebra then its free powers $A^{* n}, 2 \leq n \leq \infty$ , are mutually non-isomorphic and with trivial fundamen…

math.OA2023

Maximal amenable MASAs of radial type in the free group factors

Remi Boutonnet, Sorin Popa

We prove that if ${(M_{j}, τ_{j})}_{j \in J}$ are tracial von Neumann algebras, $s_{j} \in M_{j}$ are selfadjoint semicircular elements and $t = (t_{j})_{j}$ is a square summable $J$ -tuple of r…

math.GR2003★ 21 cited

On co-amenability for groups and von Neumann algebras

Nicolas Monod, Sorin Popa

We first show that co-amenability does not pass to subgroups, answering a question asked by Eymard in 1972. We then address co-amenability for von Neumann algebras, describing nota…

Non-isomorphism of A∗n,2≤n≤∞, for a non-separable abelian von Neumann algebra A

Maximal amenable MASAs of radial type in the free group factors

On co-amenability for groups and von Neumann algebras

Non-isomorphism of $A^{* n}, 2 \leq n \leq \infty$ , for a non-separable abelian von Neumann algebra $A$