English

Infinite measures on Cantor spaces

Dynamical Systems 2011-02-08 v1

Abstract

We study the set M(X)M_\infty(X) of all infinite full non-atomic Borel measures on a Cantor space X. For a measure μ\mu from M(X)M_\infty(X) we define a defective set Mμ={xX:foranyclopensetUwhichcontainsxwehaveμ(U)=}M_\mu = \{x \in X : for any clopen set U which contains x we have \mu(U) = \infty \}. We call a measure μ\mu from M(X)M_\infty(X) non-defective (μM0(X)\mu \in M_\infty^0(X)) if μ(Mμ)=0\mu(M_\mu) = 0. The paper is devoted to the classification of measures μ\mu from M0(X)M_\infty^0(X) with respect to a homeomorphism. The notions of goodness and clopen values set S(μ)S(\mu) are defined for a non-defective measure μ\mu. We give a criterion when two good non-defective measures are homeomorphic and prove that there exist continuum classes of weakly homeomorphic good non-defective measures on a Cantor space. For any group-like subset D[0,)D \subset [0,\infty) we find a good non-defective measure μ\mu on a Cantor space X with S(μ)=DS(\mu) = D and an aperiodic homeomorphism of X which preserves μ\mu. The set SS of infinite ergodic R-invariant measures on non-simple stationary Bratteli diagrams consists of non-defective measures. For μS\mu \in S the set S(μ)S(\mu) is group-like, a criterion of goodness is proved for such measures. We show that a homeomorphism class of a good measure from SS contains countably many distinct good measures from SS.

Keywords

Cite

@article{arxiv.1102.1072,
  title  = {Infinite measures on Cantor spaces},
  author = {Olena Karpel},
  journal= {arXiv preprint arXiv:1102.1072},
  year   = {2011}
}

Comments

23 pages

R2 v1 2026-06-21T17:22:06.993Z