Measure equivalence classification of transvection-free right-angled Artin groups

Abstract

We prove that if two transvection-free right-angled Artin groups are measure equivalent, then they have isomorphic extension graphs. As a consequence, two right-angled Artin groups with finite outer automorphism groups are measure equivalent if and only if they are isomorphic. This matches the quasi-isometry classification. However, in contrast with the quasi-isometry question, we observe that no right-angled Artin group is superrigid for measure equivalence in the strongest possible sense, for two reasons. First, a right-angled Artin group $G$ is always measure equivalent to any graph product of infinite countable amenable groups over the same defining graph. Second, when $G$ is nonabelian, the automorphism group of the universal cover of the Salvetti complex of $G$ always contains infinitely generated (non-uniform) lattices.

v3: Final accepted version

References in corpus (2)

• Boundary amenability and measure equivalence rigidity among two-dimensional Artin groups of hyperbolic type
• The asymptotic geometry of right-angled Artin groups, I

Cited by in corpus (6)

• Graphs and complexes of lattices
• Boundary amenability and measure equivalence rigidity among two-dimensional Artin groups of hyperbolic type
• Measure equivalence classification of right-angled Artin groups: the finite $\mathrm{Out}$ classes
• Rigidity for von Neumann algebras of graph product groups. I. Structure of automorphisms
• Measure equivalence rigidity of the handlebody groups
• Cocycle superrigidity from higher rank lattices to $\mathrm{Out}(F_N)$