9 citations · 26 across the 6 of their papers we have counts for
6 papers
On the vanishing cohomology problem for cocycle actions of groups on II factors
Sorin Popa
We prove that any free cocycle action of a countable amenable group on any II factor can be perturbed by inner automorphisms to a genuine action. This {\em vanishing co…
Cocycle and Orbit Equivalence Superrigidity for Malleable Actions of w-Rigid Groups
Sorin Popa
We prove that if a countable discrete group is {\it w-rigid}, i.e. it contains an infinite normal subgroup with the relative property (T) (e.g. $Γ= SL(2,\Bbb Z) \ltimes \Bb…
Some computations of 1-cohomology groups and construction of non orbit equivalent actions
Sorin Popa
For each group having an infinite normal subgroup with the relative property (T) (for instance where is infinite with property (T) and is arbitrary), a…
Strong rigidity of II factors arising from malleable actions of w-rigid groups, II
Sorin Popa
We prove that any isomorphism of group measure space II factors, , , with containi…
On the Cohomology of Actions of Groups by Bernoulli Shifts
Sorin Popa, Roman Sasyk
We prove that if is a countable, discrete group having infinite, normal subgroups with the relative property (T), then the Bernoulli shift action of on ${\underset g \in G…
Strong Rigidity of II Factors Arising from Malleable Actions of w-Rigid Groups, I
Sorin Popa
We consider cross-product II factors , with discrete ICC groups that contain infinite normal subgroups with the relative property (T) and $σ: G \to {\text…