English

Congruence Subgroups of the Virtual Braid Group

Geometric Topology 2025-10-27 v1

Abstract

We extend the notion of congruence subgroups of the braid group to the virtual braid group using an extension of the integral Burau representation. We prove that the level 2 congruence subgroup of the virtual braid group is the pure virtual braid group, recovering a virtual analogue of a result of Arnol'd. We pose several questions which highlight the difference between the classical and virtual braid groups.

Keywords

Cite

@article{arxiv.2510.21593,
  title  = {Congruence Subgroups of the Virtual Braid Group},
  author = {Wade Bloomquist and Alexa Goldberg and Nancy Scherich},
  journal= {arXiv preprint arXiv:2510.21593},
  year   = {2025}
}
R2 v1 2026-07-01T07:04:11.893Z