English

Ambiguity of {\omega}-Languages of Turing Machines

Logic in Computer Science 2015-07-01 v3 Computational Complexity Logic

Abstract

An {\omega}-language is a set of infinite words over a finite alphabet X. We consider the class of recursive {\omega}-languages, i.e. the class of {\omega}-languages accepted by Turing machines with a B\"uchi acceptance condition, which is also the class {\Sigma}11 of (effective) analytic subsets of X{\omega} for some finite alphabet X. We investigate here the notion of ambiguity for recursive {\omega}-languages with regard to acceptance by B\"uchi Turing machines. We first present in detail essentials on the literature on {\omega}-languages accepted by Turing Machines. Then we give a complete and broad view on the notion of ambiguity and unambiguity of B\"uchi Turing machines and of the {\omega}-languages they accept. To obtain our new results, we make use of results and methods of effective descriptive set theory.

Keywords

Cite

@article{arxiv.1209.5669,
  title  = {Ambiguity of {\omega}-Languages of Turing Machines},
  author = {Olivier Finkel},
  journal= {arXiv preprint arXiv:1209.5669},
  year   = {2015}
}