English

New Permutation Representations of the Braid Group

Group Theory 2008-11-27 v1

Abstract

We give a new infinite family of group homomorphisms from the braid group B_k to the symmetric group S_{mk} for all k and m \geq 2. Most known permutation representations of braids are included in this family. We prove that the homomorphisms in this family are non-cyclic and transitive. For any divisor l of m, 1\leq l < m, we prove in particular that if \frac{m}{l} is odd then there are 1 + \frac{m}{l} non-conjugate homomorphisms included in our family. We define a certain natural restriction on homomorphisms B_k to S_n, common to all homomorphisms in our family, which we term 'good', and of which there are two types. We prove that all good homomorphisms B_k to S_{mk} of type 1 are included in the infinite family of homomorphisms we gave. For m=3, we prove that all good homomorphisms B_k to S_{3k} of type 2 are also included in this family. Finally, we refute a conjecture made by Matei and Suciu regarding permutation representations of braids and give an updated conjecture.

Keywords

Cite

@article{arxiv.0811.4204,
  title  = {New Permutation Representations of the Braid Group},
  author = {Amiel Ferman and Tahl Nowik and Robert Schwartz and Mina Teicher},
  journal= {arXiv preprint arXiv:0811.4204},
  year   = {2008}
}

Comments

64pp

R2 v1 2026-06-21T11:45:21.154Z