8 papers
Invariant subalgebras of von Neumann algebras arising from negatively curved groups
Ionut Chifan, Sayan Das, Bin Sun
Using an interplay between geometric methods in group theory and soft von Neuman algebraic techniques we prove that for any icc, acylindrically hyperbolic group its von Neumann…
Agrarian and -Betti numbers of locally indicable groups, with a twist
Dawid Kielak, Bin Sun
We prove that twisted -Betti numbers of locally indicable groups are equal to the usual -Betti numbers rescaled by the dimension of the twisting representation; thi…
Wreath-like products of groups and their von Neumann algebras I: -superrigidity
Ionut Chifan, Adrian Ioana, Denis Osin +1
We introduce a new class of groups called wreath-like products. These groups are close relatives of the classical wreath products and arise naturally in the context of group theore…
Cohomology of group theoretic Dehn fillings II
Nansen Petrosyan, Bin Sun
We study the cohomology of group theoretic Dehn fillings. Applying the Cohen-Lyndon property for sufficiently deep Dehn fillings of hyperbolically embedded subgroups $H\hookrightar…
Cohomology of group theoretic Dehn fillings II: A spectral sequence
Bin Sun
This is the second paper in a series of three papers aiming to study cohomology of group theoretic Dehn fillings. In the present paper, we derive a spectral sequence for Cohen-Lynd…
Cohomology of group theoretic Dehn fillings I: Cohen-Lyndon type theorems
Bin Sun
This is the first paper of two papers in a row aiming to study cohomology of group theoretic Dehn fillings. In the present paper, we prove a particular free product structure, whic…