arXiv subjects

Basile Morando

Publications and source records attributed to Basile Morando.

2 recordsLinked to original sources

arXiv2025

The regular representation of Neretin groups is factorial

We show that the left regular representation of Neretin groups is factorial, providing the first example of a non-discrete simple group with this property. This is based on a new criterion of factoriality for totally disconnected groups. For groups G satisfying the criterion, we determine the type of the factor L(G) and derive factoriality results for crossed products associated to G-actions on von Neumann algebras.

math.OA↗

arXiv2024

Strictly outer actions of locally compact groups: beyond the full factor case

We show that, given a continuous action $\alpha$ of a locally compact group $G$ on a factor $M$, the relative commutant $M'\cap(M\rtimes_{\alpha} G)$ is contained in $M\rtimes_{\alpha} H$ where $H$ is the subgroup of elements acting without spectral gap. As a corollary, we answer a question of Marrakchi and Vaes by showing that if $M$ is semifinite and $\alpha_g$ is not approximately inner for all $g\neq 1$, then $M'\cap (M\rtimes_{\alpha} G)=\mathbb{C}$.

math.OA↗