{ "id": "1811.02250", "version": "v1", "published": "2018-11-06T09:32:33.000Z", "updated": "2018-11-06T09:32:33.000Z", "title": "Profinite groups with a cyclotomic $p$-orientation", "authors": [ "Claudio Quadrelli", "Thomas Weigel" ], "comment": "34 pages", "categories": [ "math.GR", "math.NT" ], "abstract": "Profinite groups with a cyclotomic $p$-orientation are introduced and studied. The special interest in this class of groups arises from the fact that any absolute Galois group $G_{K}$ of a field $K$ is indeed a profinite group with a cyclotomic $p$-orientation $\\theta_{K,p}\\colon G_{K}\\to\\mathbb{Z}_p^\\times$ which is even Bloch-Kato. The same is true for its maximal pro-$p$ quotient $G_{K}(p)$ provided the field $K$ contains a primitive $p^{th}$-root of unity. The class of cyclotomically $p$-oriented profinite groups (resp. pro-$p$ groups) which are Bloch-Kato is closed with respect to inverse limits, free product and certain fibre products. For profinite groups with a cyclotomic $p$-orientation the classical Artin-Schreier theorem holds. Moreover, Bloch-Kato pro-$p$ groups with a cyclotomic orientation satisfy a strong form of Tits' alternative, and the elementary type conjecture formulated by I. Efrat can be restated that the only finitely generated indecomposable torsion free Bloch-Kato pro-$p$ groups with a cyclotomic orientation should be Poincar\\'e duality pro-$p$ groups of dimension less or equal to $2$.", "revisions": [ { "version": "v1", "updated": "2018-11-06T09:32:33.000Z" } ], "analyses": { "subjects": [ "20E18", "12G05" ], "keywords": [ "profinite group", "elementary type conjecture", "absolute galois group", "generated indecomposable torsion free bloch-kato", "classical artin-schreier theorem holds" ], "note": { "typesetting": "TeX", "pages": 34, "language": "en", "license": "arXiv", "status": "editable" } } }