3 papers
math.OA2016
Maximal amenable MASAs of the free group factor of two generators arising from the free products of hyperfinite factors
Koichi Shimada
In this paper, we give examples of maximal amenable subalgebras of the free group factor of two generators. More precisely, we consider two copies of the hyperfinite factor o…
math.OA2016
Maximal amenability of the generator subalgebra in -Gaussian von Neumann algebras
Sandeepan Parekh, Koichi Shimada, Chenxu Wen
In this article, we give explicit examples of maximal amenable subalgebras of the -Gaussian algebras, namely, the generator subalgebra is maximal amenable inside the -Gaussia…
math.OA2014
Classification of actions of compact abelian groups on subfactors with index less than 4
Koichi Shimada
We calssify actions of discrete abelian groups on some inclusions of von Neumann algebras, up to cocycle conjugacy. As an application, we classify actions of compact abelian groups…