Relative solidity for biexact groups in measure equivalence

Changying Ding; Daniel Drimbe

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arXiv · 2503.24167

Relative solidity for biexact groups in measure equivalence

Changying Ding·Daniel Drimbe

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Abstract

We demonstrate a relative solidity property for the product of a nonamenable biexact group with an arbitrary infinite group in the measure equivalence setting. Among other applications, we obtain the following unique product decomposition for products of nonamenable biexact groups, strengthening \cite{Sa09}: for any nonamenable biexact groups $Γ_1,\cdots, Γ_n$, if a product group $Λ_1\times Λ_2$ is measure equivalent to $\times_{k=1}^nΓ_k$, then there exists a partition $T_1\sqcup T_2=\{1,\dots, n\}$ such that $Λ_i$ is measure equivalent to $\times_{k\in T_i}Γ_k$ for $i=1,2$.

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Changying Ding, Daniel Drimbe. 2025-03-31. Relative solidity for biexact groups in measure equivalence. https://arxiv.org/abs/2503.24167

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