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 , 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.
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}
}