Isometric extensions, 2-cocycles and ergodicity of skew products

• Autorzy: Alexandre I. Danilenko , Mariusz Lemańczyk
• Języki publikacji: EN

Abstrakty

EN

We establish existence and uniqueness of a canonical form for isometric extensions of an ergodic non-singular transformation T. This is applied to describe the structure of commutors of the isometric extensions. Moreover, for a compact group G, we construct a G-valued T-cocycle α which generates the ergodic skew product extension $T_α$ and admits a prescribed subgroup in the centralizer of $T_α$.

Słowa kluczowe

EN

ergodic transformation; cocycle; isometric extension

Kategorie tematyczne

• 28D05: Measure-preserving transformations

• Wydawca: Institute of Mathematics Polish Academy of Sciences
• Czasopismo: Studia Mathematica
• Rocznik: 1999
• Tom: 137
• Numer: 2
• Strony: 123-142

Daty

wydano

1999

otrzymano

1997-09-22

poprawiono

1999-08-30

Twórcy

autor

Alexandre I. Danilenko

• Department of Mechanics and Mathematics, Kharkov State University, Freedom sq. 4 Kharkov, 310077, Ukraine,

autor

Mariusz Lemańczyk

• Faculty of Mathematics and Computer Science, Nicholas Copernicus University, Chopina 12/18, 87-100 Toruń, Poland,

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