English

Turing degree spectra of minimal subshifts

Formal Languages and Automata Theory 2014-09-18 v3 Discrete Mathematics Logic in Computer Science

Abstract

Subshifts are shift invariant closed subsets of ΣZd\Sigma^{\mathbb{Z}^d} , minimal subshifts are subshifts in which all points contain the same patterns. It has been proved by Jeandel and Vanier that the Turing degree spectra of non-periodic minimal subshifts always contain the cone of Turing degrees above any of its degree. It was however not known whether each minimal subshift's spectrum was formed of exactly one cone or not. We construct inductively a minimal subshift whose spectrum consists of an uncountable number of cones with disjoint base.

Keywords

Cite

@article{arxiv.1408.6487,
  title  = {Turing degree spectra of minimal subshifts},
  author = {Michael Hochman and Pascal Vanier},
  journal= {arXiv preprint arXiv:1408.6487},
  year   = {2014}
}