English

FPn properties of generalized Houghton groups

Group Theory 2016-08-03 v1

Abstract

This Thesis presents a 2-dimensional generalization of Houghtons' groups H_n. H_n is defined to be the group of all permutations p of a disjoint union of copies of the natural numbers N, with the property that each copy of N contains a cofinite subset on which p restricts to a translation. Our group G(n) is defined to be the group of all permutations p of a disjoint union of quadrants (i.e., copies of NxN) with the property that each quadrant contains a subquadrant on which p is a translation, while p restricted to the remaining set is piecewise isometric on a cofinite disjoint union of rays (each isometric to N). Based on K.S. Brown's treatment of the Houghton group case it is shown that G(n) is of type FP(n-1); in fact, that G(n) contains a normal subgroup N with G(n)/N = Z^(n-1) which is of type FP(n-1) and not FPn.

Keywords

Cite

@article{arxiv.1608.00933,
  title  = {FPn properties of generalized Houghton groups},
  author = {Heike Sach},
  journal= {arXiv preprint arXiv:1608.00933},
  year   = {2016}
}

Comments

This was a Frankfurt diploma thesis (1992), supervisor R. Bieri, 49 pages, in German, 21 figures