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Continuous orbit equivalence up to equivalence relations

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 نشر من قبل XiangQi Qiang
 تاريخ النشر 2021
  مجال البحث
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We introduce notions of continuous orbit equivalence and strong (respective, weak) continuous orbit equivalence for automorphism systems of {e}tale equivalence relations, and characterize them in terms of the semi-direct product groupoids, as well as their reduced groupoid $C^*$-algebras with canonical Cartan subalgebras. In particular, we study topological rigidity of expansive automorphism actions on compact (connected) metrizable groups.



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