Dehn quandles of groups and orientable surfaces

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Dhanwani, Neeraj K., Raundal, Hitesh, Singh, Mahender
Format: Preprint
Published: 2021
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866911910817955840
author Dhanwani, Neeraj K.
Raundal, Hitesh
Singh, Mahender
author_facet Dhanwani, Neeraj K.
Raundal, Hitesh
Singh, Mahender
contents Unifying various constructions of quandles including Coxeter quandles, free quandles, knot quandles of prime knots and Dehn quandles of orientable surfaces, we introduce Dehn quandles of groups with respect to their subsets. It turns out that Dehn quandles are precisely the ones that embed naturally into their enveloping groups. We prove that the enveloping group of the Dehn quandle of a given group with respect to its generating set is a central extension of that group, and that enveloping groups of Dehn quandles of Artin groups and link groups with respect to their standard generating sets are the groups themselves. We discuss orderability of Dehn quandles and prove that free involutory quandles are left orderable, whereas certain generalised Alexander quandles are bi-orderable. Specialising to surfaces, we give generating sets for Dehn quandles of orientable surfaces with punctures and compute their automorphism groups. As applications, we recover a result of Niebrzydowski and Przytycki proving that the knot quandle of the trefoil knot is isomorphic to the Dehn quandle of the torus and also extend a result of Yetter on epimorphisms of Dehn quandles of orientable surfaces onto certain involutory homological quandles.
format Preprint
id arxiv_https___arxiv_org_abs_2106_00290
institution arXiv
publishDate 2021
record_format arxiv
spellingShingle Dehn quandles of groups and orientable surfaces
Dhanwani, Neeraj K.
Raundal, Hitesh
Singh, Mahender
Geometric Topology
Group Theory
2020: Primary 57K10, 57K20, Secondary 57K12
Unifying various constructions of quandles including Coxeter quandles, free quandles, knot quandles of prime knots and Dehn quandles of orientable surfaces, we introduce Dehn quandles of groups with respect to their subsets. It turns out that Dehn quandles are precisely the ones that embed naturally into their enveloping groups. We prove that the enveloping group of the Dehn quandle of a given group with respect to its generating set is a central extension of that group, and that enveloping groups of Dehn quandles of Artin groups and link groups with respect to their standard generating sets are the groups themselves. We discuss orderability of Dehn quandles and prove that free involutory quandles are left orderable, whereas certain generalised Alexander quandles are bi-orderable. Specialising to surfaces, we give generating sets for Dehn quandles of orientable surfaces with punctures and compute their automorphism groups. As applications, we recover a result of Niebrzydowski and Przytycki proving that the knot quandle of the trefoil knot is isomorphic to the Dehn quandle of the torus and also extend a result of Yetter on epimorphisms of Dehn quandles of orientable surfaces onto certain involutory homological quandles.
title Dehn quandles of groups and orientable surfaces
topic Geometric Topology
Group Theory
2020: Primary 57K10, 57K20, Secondary 57K12
url https://arxiv.org/abs/2106.00290