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arXiv · 2205.12137

Sofic approximations and quantitative measure couplings

Amandine Escalier
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Abstract

We build quantitative measure subgroup couplings from a Brieussel-Zheng diagonal product to a lamplighter group. We use them to answer the inverse problem of the quantification; namely, find a group admitting a measure subgroup coupling with a prescribed group with prescribed quantification, in the case of the lamplighter group.

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Amandine Escalier. 2022-05-24. Sofic approximations and quantitative measure couplings. https://doi.org/10.1215/00192082-11996711

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