Dehn Functions, the Word Problem, and the Bounded Word Problem For Decidable Group Presentations
Abstract
We construct examples of finitely generated decidable group presentations that satisfy certain combinations of solvability for the word problem, solvability for the bounded word problem, and computablity for the Dehn function. We prove that no finitely generated decidable presentations exist satisfying the combinations for which we do not provide examples. The presentations we construct are also minimal. These constructions answer an open question asked by R.I. Grigorchuk and S.V. Ivanov. Our approach uses machinery developed by Birget, Ol'shanskii, Rips, and Sapir for constructing finite group presentations that simulate Turing machines. We generalize this machinery to construct finitely generated decidable group presentations that simulate computing objects similar to oracle Turing machines.
 Publication:

arXiv eprints
 Pub Date:
 December 2012
 arXiv:
 arXiv:1212.2024
 Bibcode:
 2012arXiv1212.2024C
 Keywords:

 Mathematics  Group Theory;
 20F05;
 20F06;
 20F10
 EPrint:
 Fixed typos and grammatical errors that appeared throughout the first version. arXiv admin note: text overlap with arXiv:math/9811105 by other authors