Groups that do and do not have context-sensitive word problem
Group Theory
2008-01-30 v1
Abstract
We prove that a group has word problem that is a growing context-sensitive language precisely if its word problem can be solved using a non-deterministic Cannon's algorithm (the deterministic algorithms being defined by Goodman and Shapiro). We generalise their results to find many examples of groups not admitting non-deterministic Cannon's algorithms. This adds to the examples of Kambites and Otto of groups separating context-sensitive and growing context-sensitive word problems, and provides a new language-theoretic separation result.
Cite
@article{arxiv.0801.4533,
title = {Groups that do and do not have context-sensitive word problem},
author = {Derek F. Holt and Sarah Rees and Michael Shapiro},
journal= {arXiv preprint arXiv:0801.4533},
year = {2008}
}