English

Very badly ordered cycles of interval maps

Dynamical Systems 2021-12-21 v2

Abstract

We prove that a periodic orbit PP with coprime over-rotation pair is an over-twist periodic orbit iff the PP-linear map has the over-rotation interval with left endpoint equal to the over-rotation number of PP. We then show that this result fails if the over-rotation pair of PP is not coprime. Examples of patterns with non-coprime over-rotation pairs are given so that these patterns have no block structure over over-twists but have over-rotation number equal to the left endpoint of the forced over-rotation interval (such patterns are called \emph{very badly ordered}). This presents a situation in which the results about over-rotation numbers on the interval and those about classical rotation numbers for circle degree one maps are different. In the end we elucidate a rigorous description of the strongest unimodal pattern that corresponds to a given over-rotation interval and use it to construct unimodal very badly ordered patterns with arbitrary non-coprime over-rotation pair.

Keywords

Cite

@article{arxiv.1908.06145,
  title  = {Very badly ordered cycles of interval maps},
  author = {Sourav Bhattacharya and Alexander Blokh},
  journal= {arXiv preprint arXiv:1908.06145},
  year   = {2021}
}

Comments

19 pages, 5 figures; in this version 4 typos are corrected and one figure is improved; to appear in Journal of Difference Equations and Applications

R2 v1 2026-06-23T10:49:29.448Z