English

Virtual planar braid groups and permutations

Group Theory 2025-10-17 v2 Geometric Topology

Abstract

Twin groups and virtual twin groups are planar analogues of braid groups and virtual braid groups, respectively. These groups play the role of braid groups in the Alexander-Markov correspondence for the theory of stable isotopy classes of immersed circles on orientable surfaces. Motivated by the general idea of Artin and a recent work of Bellingeri and Paris \cite{BellingeriParis2020}, we obtain a complete description of homomorphisms between virtual twin groups and symmetric groups, which as an application gives us the precise structure of the automorphism group of the virtual twin group VTnVT_n on n2n \ge 2 strands. This is achieved by showing the existence of an irreducible right-angled Coxeter group KTnKT_n inside VTnVT_n. As a by-product, it also follows that the twin group TnT_n embeds inside the virtual twin group VTnVT_n, which is an analogue of a similar result for braid groups.

Keywords

Cite

@article{arxiv.2109.13035,
  title  = {Virtual planar braid groups and permutations},
  author = {Tushar Kanta Naik and Neha Nanda and Mahender Singh},
  journal= {arXiv preprint arXiv:2109.13035},
  year   = {2025}
}

Comments

29 pages, 4 figures, 2 tables