{ "id": "2405.14287", "version": "v1", "published": "2024-05-23T08:02:41.000Z", "updated": "2024-05-23T08:02:41.000Z", "title": "Maps, simple groups, and arc-transitive graphs", "authors": [ "Martin W. Liebeck", "Cheryl E. Praeger" ], "comment": "48 pages (including 6 pages of results tables at the end)", "categories": [ "math.GR", "math.CO" ], "abstract": "We determine all factorisations $X=AB$, where $X$ is a finite almost simple group and $A,B$ are core-free subgroups such that $A\\cap B$ is cyclic or dihedral. As a main application, we classify the graphs $\\Gamma$ admitting an almost simple arc-transitive group $X$ of automorphisms, such that $\\Gamma$ has a 2-cell embedding as a map on a closed surface admitting a core-free arc-transitive subgroup $G$ of $X$. We prove that apart from the case where $X$ and $G$ have socles $A_n$ and $A_{n-1}$ respectively, the only such graphs are the complete graphs $K_n$ with $n$ a prime power, the Johnson graphs $J(n,2)$ with $n-1$ a prime power, and 14 further graphs. In the exceptional case, we construct infinitely many graph embeddings.", "revisions": [ { "version": "v1", "updated": "2024-05-23T08:02:41.000Z" } ], "analyses": { "subjects": [ "20B25", "20D06", "20D08", "05C25" ], "keywords": [ "simple group", "arc-transitive graphs", "prime power", "core-free subgroups", "johnson graphs" ], "note": { "typesetting": "TeX", "pages": 48, "language": "en", "license": "arXiv", "status": "editable" } } }