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Set-theoretical entropies of generalized shifts

Dynamical Systems 2018-06-12 v2

Abstract

In the following text for arbitrary XX with at least two elements, nonempty set Γ\Gamma and self-map φ:ΓΓ\varphi:\Gamma\to\Gamma we prove the set-theoretical entropy of generalized shift σφ:XΓXΓ\sigma_\varphi:X^\Gamma\to X^\Gamma (σφ((xα)αΓ)=(xφ(α))αΓ\sigma_\varphi((x_\alpha)_{\alpha\in\Gamma})=(x_{\varphi(\alpha)})_{\alpha\in\Gamma} (for (xα)αΓXΓ(x_\alpha)_{\alpha\in\Gamma}\in X^\Gamma)) is either zero or infinity, moreover it is zero if and only if φ\varphi is quasi-periodic. We continue our study on contravariant set-theoretical entropy of generalized shift and motivate the text using counterexamples dealing with algebraic, topological, set-theoretical and contravariant set-theoretical positive entropies of generalized shifts.

Keywords

Cite

@article{arxiv.1709.01579,
  title  = {Set-theoretical entropies of generalized shifts},
  author = {Zahra Nili Ahmadabadi and Fatemah Ayatollah Zadeh Shirazi},
  journal= {arXiv preprint arXiv:1709.01579},
  year   = {2018}
}

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12 pages