Vol. 195, No. 2, 2000

Download This Article
Download this article. For Screen
For Printing
Recent Issues
Vol. 332: 1  2
Vol. 331: 1  2
Vol. 330: 1  2
Vol. 329: 1  2
Vol. 328: 1  2
Vol. 327: 1  2
Vol. 326: 1  2
Vol. 325: 1  2
Online Archive
Volume:
Issue:
     
The Journal
About the journal
Ethics and policies
Peer-review process
 
Submission guidelines
Submission form
Editorial board
Officers
 
Subscriptions
 
ISSN 1945-5844 (electronic)
ISSN 0030-8730 (print)
 
Special Issues
Author index
To appear
 
Other MSP journals

Nicholas S. Ormes

Abstract

In this paper we investigate the role of real-valued coboundaries for classifying of minimal homeomorphisms of the Cantor set. This work follows the work of Giordano, Putnam, and Skau who showed that one can use integer-valued coboundaries to characterize minimal homeomorphisms up to strong orbit equivalence. First, we prove a rigidity result. We show that there is an orbit equivalence between minimal Cantor systems which preserves real-valued coboundaries if and only if the systems are flip conjugate. Second, we investigate a real analogue of the dynamical unital ordered cohomology group studied by Giordano, Putnam and Skau. We show that, in general, isomorphism of our unital ordered vector space determines a weaker relation than strong orbit equivalence and we characterize this relation in a certain finite dimensional case. Finally, we consider isomorphisms of this vector space which preserve the cohomology subgroup. We show that such an isomorphism gives rise to a strictly stronger relation than strong orbit equivalence. In particular, it determines topological discrete spectrum, but does not determine systems up to flip conjugacy.

In this paper we investigate the role of real-valued coboundaries for classifying of minimal homeomorphisms of the Cantor set. This work follows the work of Giordano, Putnam, and Skau who showed that one can use integer-valued coboundaries to characterize minimal homeomorphisms up to strong orbit equivalence. First, we prove a rigidity result. We show that there is an orbit equivalence between minimal Cantor systems which preserves real-valued coboundaries if and only if the systems are flip conjugate. Second, we investigate a real analogue of the dynamical unital ordered cohomology group studied by Giordano, Putnam and Skau. We show that, in general, isomorphism of our unital ordered vector space determines a weaker relation than strong orbit equivalence and we characterize this relation in a certain finite dimensional case. Finally, we consider isomorphisms of this vector space which preserve the cohomology subgroup. We show that such an isomorphism gives rise to a strictly stronger relation than strong orbit equivalence. In particular, it determines topological discrete spectrum, but does not determine systems up to flip conjugacy.

In this paper we investigate the role of real-valued coboundaries for classifying of minimal homeomorphisms of the Cantor set. This work follows the work of Giordano, Putnam, and Skau who showed that one can use integer-valued coboundaries to characterize minimal homeomorphisms up to strong orbit equivalence. First, we prove a rigidity result. We show that there is an orbit equivalence between minimal Cantor systems which preserves real-valued coboundaries if and only if the systems are flip conjugate. Second, we investigate a real analogue of the dynamical unital ordered cohomology group studied by Giordano, Putnam and Skau. We show that, in general, isomorphism of our unital ordered vector space determines a weaker relation than strong orbit equivalence and we characterize this relation in a certain finite dimensional case. Finally, we consider isomorphisms of this vector space which preserve the cohomology subgroup. We show that such an isomorphism gives rise to a strictly stronger relation than strong orbit equivalence. In particular, it determines topological discrete spectrum, but does not determine systems up to flip conjugacy.

In this paper we investigate the role of real-valued coboundaries for classifying of minimal homeomorphisms of the Cantor set. This work follows the work of Giordano, Putnam, and Skau who showed that one can use integer-valued coboundaries to characterize minimal homeomorphisms up to strong orbit equivalence. First, we prove a rigidity result. We show that there is an orbit equivalence between minimal Cantor systems which preserves real-valued coboundaries if and only if the systems are flip conjugate. Second, we investigate a real analogue of the dynamical unital ordered cohomology group studied by Giordano, Putnam and Skau. We show that, in general, isomorphism of our unital ordered vector space determines a weaker relation than strong orbit equivalence and we characterize this relation in a certain finite dimensional case. Finally, we consider isomorphisms of this vector space which preserve the cohomology subgroup. We show that such an isomorphism gives rise to a strictly stronger relation than strong orbit equivalence. In particular, it determines topological discrete spectrum, but does not determine systems up to flip conjugacy.

In this paper we investigate the role of real-valued coboundaries for classifying of minimal homeomorphisms of the Cantor set. This work follows the work of Giordano, Putnam, and Skau who showed that one can use integer-valued coboundaries to characterize minimal homeomorphisms up to strong orbit equivalence. First, we prove a rigidity result. We show that there is an orbit equivalence between minimal Cantor systems which preserves real-valued coboundaries if and only if the systems are flip conjugate. Second, we investigate a real analogue of the dynamical unital ordered cohomology group studied by Giordano, Putnam and Skau. We show that, in general, isomorphism of our unital ordered vector space determines a weaker relation than strong orbit equivalence and we characterize this relation in a certain finite dimensional case. Finally, we consider isomorphisms of this vector space which preserve the cohomology subgroup. We show that such an isomorphism gives rise to a strictly stronger relation than strong orbit equivalence. In particular, it determines topological discrete spectrum, but does not determine systems up to flip conjugacy.

Authors
Nicholas S. Ormes
Department of Mathematics
University of Texas
Austin, TX 78712