Normalizers inside Amalgamated Free Product von Neumann Algebras
Normalizers inside Amalgamated Free Product von Neumann Algebras
Recently, Adrian Ioana proved that all crossed products L^\infty(X) \rtimes (\Gamma_1*\Gamma_2) by free ergodic probability measure preserving actions of a nontrivial free product group \Gamma_1 * \Gamma_2 have a unique Cartan subalgebra up to unitary conjugacy. Ioana deduced this result from a more general dichotomy theorem on the normalizer \mathcal …