• Corpus ID: 253447111

An upgrading theorem for properly proximal von Neumann algebras

@inproceedings{Ding2022AnUT,
  title={An upgrading theorem for properly proximal von Neumann algebras},
  author={Changying Ding and Srivatsav Kunnawalkam Elayavalli},
  year={2022}
}
Using computations in the bidual of $\mathbb{B}(L^2M)$ we develop a technique at the von Neumann algebra level to upgrade relative proper proximality to full proper proximality in the presence of some mixing and non co-amenability assumptions. This is used to classify subalgebras of $L\Gamma$ where $\Gamma$ is an infinite group that is biexact relative to a finite family of subgroups $\{\Lambda_i\}_{i\in I}$ such that each $\Lambda_i$ is almost malnormal in $\Gamma$. As an application we obtain… 
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