Speedups and orbit equivalence of finite extensions of ergodic Z-actions
نویسندگان
چکیده
We classify n-point extensions of ergodic Z-actions up to relative orbit equivalence and establish criteria under which one n-point extension of an ergodic Z-action can be sped up to be relatively isomorphic to an n-point extension of another ergodic Z-action. Both results are characterized in terms of an algebraic object associated to each n-point extension which is a conjugacy class of subgroups of the symmetric group on n elements.
منابع مشابه
Speedups and orbit equivalence of finite extensions of ergodic Zd-actions
We classify n-point extensions of ergodic Z-actions up to relative orbit equivalence and establish criteria under which one n-point extension of an ergodic Z-action can be sped up to be relatively isomorphic to an n-point extension of another ergodic Z-action. Both results are characterized in terms of an algebraic object associated to each n-point extension which is a conjugacy class of subgro...
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