Israel Journal of Mathematics

, Volume 57, Issue 1, pp 28–48 | Cite as

Factor orbit equivalence of compact group extensions and classification of finite extensions of ergodic automorphisms

  • Marlies Gerber


In §§1–5, we classifyn-point extensions of ergodic automorphisms up to factor orbit-equivalence (which is the natural analogue of factor isomorphism). This classification is in terms of conjugacy classes of subgroups of the symmetric group onn points, and parallels D. Rudolph’s classification ofn-point extensions of Bernoulli shifts up to factor isomorphism. In §6, we give another proof of A. Fieldsteel’s theorem on factor orbit-equivalence of compact group extensions.


Conjugacy Class Symmetric Group Pairwise Disjoint Lebesgue Space Ergodic Measure 
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Copyright information

© The Weizmann Science Press of Israel 1987

Authors and Affiliations

  • Marlies Gerber
    • 1
  1. 1.Department of MathematicsIndiana UniversityBloomingtonUSA

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