A Computational Trichotomy for Connectivity of Boolean Satisfiability
Abstract
For Boolean satisfiability problems, the structure of the solution space is characterized by the solution graph, where the vertices are the solutions, and two solutions are connected iff they differ in exactly one variable. In 2006, Gopalan et al. studied connectivity properties of the solution graph and related complexity issues for CSPs, motivated mainly by research on satisfiability algorithms and the satisfiability threshold. They proved dichotomies for the diameter of connected components and for the complexity of the st-connectivity question, and conjectured a trichotomy for the connectivity question. Building on this work, we here prove the trichotomy: Connectivity is either in P, coNP-complete, or PSPACE-complete. Also, we correct a minor mistake of Gopalan et al., which leads to a slight shift of the boundaries towards the hard side.
Cite
@article{arxiv.1312.4524,
title = {A Computational Trichotomy for Connectivity of Boolean Satisfiability},
author = {Konrad W. Schwerdtfeger},
journal= {arXiv preprint arXiv:1312.4524},
year = {2015}
}
Comments
27 pages; severe error in the proof of Lemma 19 (now Lemma 23) corrected; all results remain true, but some new definitions and lemmas were necessary; also, a further error of Gopalan et al.'s paper is explained and corrected; several other improvements. Text overlap with arXiv:cs/0609072 due to corrections of that paper