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arXiv · 2504.17914

Etale equivalence relations with certain prescribed torsion in their homology

Michael Francesco Ala·Hung-Chang Liao·Aaron Tikuisis
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Abstract

Given a non-cyclic simple dimension group D and a subgroup E of Q/Z, we produce a minimal \'etale equivalence relation R such that H_0(\R) is isomorphic to D \oplus E, where H_0(R) denotes the zeroth homology group of R. The equivalence relation R arises by combining tail-equivalence on a Bratteli diagram with a partial homeomorphism.

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Michael Francesco Ala, Hung-Chang Liao, Aaron Tikuisis. 2025-04-24. Etale equivalence relations with certain prescribed torsion in their homology. https://arxiv.org/abs/2504.17914

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