Saved in:
Bibliographic Details
Main Authors: Chen, Jiyong, Tang, Yi Xiao
Format: Preprint
Published: 2026
Subjects:
Online Access:https://arxiv.org/abs/2603.08129
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866918379904827392
author Chen, Jiyong
Tang, Yi Xiao
author_facet Chen, Jiyong
Tang, Yi Xiao
contents Orientably-regular maps are highly symmetric embeddings of graphs in oriented surfaces. Among them, chiral maps are those which fail to be isomorphic to their mirror images. We prove that, as $n\to\infty$, chirality is generic for orientably-regular maps with automorphism groups $S_n$ or $A_n$: the proportion of chiral maps tends to $1$ in both families. We also obtain the corresponding asymptotic result for orientably-regular hypermaps with automorphism groups $S_n$ or $A_n$. A key ingredient is a sharp asymptotic generation statement: if one chooses an involution of $S_n$ uniformly at random and then chooses an independent uniformly random element of $S_n$, the probability that these two elements generate $S_n$ and $A_n$ tends to $\frac{3}{4}$ and $\frac{1}{4}$ as $n\to\infty$, respectively.
format Preprint
id arxiv_https___arxiv_org_abs_2603_08129
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Proportion of chiral maps with automorphism group $\mathcal{S}_n$ and $\mathcal{A}_n$
Chen, Jiyong
Tang, Yi Xiao
Group Theory
Combinatorics
Orientably-regular maps are highly symmetric embeddings of graphs in oriented surfaces. Among them, chiral maps are those which fail to be isomorphic to their mirror images. We prove that, as $n\to\infty$, chirality is generic for orientably-regular maps with automorphism groups $S_n$ or $A_n$: the proportion of chiral maps tends to $1$ in both families. We also obtain the corresponding asymptotic result for orientably-regular hypermaps with automorphism groups $S_n$ or $A_n$. A key ingredient is a sharp asymptotic generation statement: if one chooses an involution of $S_n$ uniformly at random and then chooses an independent uniformly random element of $S_n$, the probability that these two elements generate $S_n$ and $A_n$ tends to $\frac{3}{4}$ and $\frac{1}{4}$ as $n\to\infty$, respectively.
title Proportion of chiral maps with automorphism group $\mathcal{S}_n$ and $\mathcal{A}_n$
topic Group Theory
Combinatorics
url https://arxiv.org/abs/2603.08129