English

Non-solvable torsion-free virtually solvable groups

Group Theory 2025-06-05 v8

Abstract

There are perfect Bieberbach groups of Hirsch length 15, but none in lower dimensions. We shall show that a nonsolvable, torsion free, virtually solvable group SS must have Hirsch length h(S)10h(S)\geq10. If h(S)13h(S)\leq13 then we may assume that A5A_5 is the only simple factor, but PSL(2,7)PSL(2,7) and SL(2,8)SL(2,8) may occur when h(S)14h(S)\geq14. There are no known examples with h(S)<15h(S)<15.

Cite

@article{arxiv.2302.09513,
  title  = {Non-solvable torsion-free virtually solvable groups},
  author = {Jonathan A. Hillman},
  journal= {arXiv preprint arXiv:2302.09513},
  year   = {2025}
}

Comments

v2: Results in \S5 and \S7 sharpened. Reference [5] updated. v3: New \S8, using torsion in crystallographic quotients. v4:Theorem 20 corrected, \S8 expanded. v5: Lemmas 4 and 7, and Sections 5 and 8 rewritten. v6: Reorganised. v: PSL(2,7) and SL(2,8) excluded in dimensions $<14$

R2 v1 2026-06-28T08:43:44.578Z