{ "id": "2109.06693", "version": "v1", "published": "2021-09-14T13:53:10.000Z", "updated": "2021-09-14T13:53:10.000Z", "title": "On the realization of subgroups of $PGL(2,F)$, and their automorphism groups, as Galois groups over function fields", "authors": [ "Rod Gow", "Gary McGuire" ], "categories": [ "math.NT", "math.AG", "math.GR" ], "abstract": "Let $F$ be any field. We give a short and elementary proof that any finite subgroup $G$ of $PGL(2,F)$ occurs as a Galois group over the function field $F(x)$. We also develop a theory of descent to subfields of $F$. This enables us to realize the automorphism groups of finite subgroups of $PGL(2,F)$ as Galois groups.", "revisions": [ { "version": "v1", "updated": "2021-09-14T13:53:10.000Z" } ], "analyses": { "subjects": [ "12F12", "11S20" ], "keywords": [ "galois group", "function field", "automorphism groups", "finite subgroup", "realization" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }