3 problems

Let $\Gamma$ be a countable subgroup of a Lie group $G$. Let $\Gamma$ act on $G$ by left translation, and equip $G$ with its Haar measure, which the action preserves. The resulting…

The Poisson equivalence-relation conjecture. The group $G$ is sofic if and only if the measured equivalence relation $\mathcal{R}$ is sofic. This is presented as a locally compact…

Let ${\mathcal R}$ be a standard equivalence relation on a standard probability space. Its groupoid ring is ${\mathbb Z}{\mathcal R}$, and ${\mathcal N}({\mathcal R})$ is the assoc…