English

On the lower central series of some virtual knot groups

Geometric Topology 2020-07-21 v2

Abstract

We study groups of some virtual knots with small number of crossings and prove that there is a virtual knot with long lower central series which, in particular, implies that there is a virtual knot with residually nilpotent group. This gives a possibility to construct invariants of virtual knots using quotients by terms of the lower central series of knot groups. Also, we study decomposition of virtual knot groups as semi direct product and free product with amalgamation. In particular, we prove that the groups of some virtual knots are extensions of finitely generated free groups by infinite cyclic groups.

Keywords

Cite

@article{arxiv.1811.09434,
  title  = {On the lower central series of some virtual knot groups},
  author = {Valeriy G. Bardakov and Neha Nanda and Mikhail V. Neshchadim},
  journal= {arXiv preprint arXiv:1811.09434},
  year   = {2020}
}

Comments

20 pages, 8 figures modified, section 3 added