{ "id": "math/0112319", "version": "v1", "published": "2001-12-04T00:00:00.000Z", "updated": "2001-12-04T00:00:00.000Z", "title": "Extensions of number fields with wild ramification of bounded depth", "authors": [ "Farshid Hajir", "Christian Maire" ], "categories": [ "math.NT" ], "abstract": "We consider p-extensions of number fields such that the filtration of the Galois group by higher ramification groups is of prescribed finite length. We extend well-known properties of tame extensions to this more general setting; for instance, we show that these towers, when infinite, are ``asymptotically good'' (an explicit bound for the root discriminant is given). We study the difficult problem of bounding the relation-rank of the Galois groups in question. Results of Gordeev and Wingberg imply that the relation-rank can tend to infinity when the set of ramified primes is fixed but the length of the ramification filtration becomes large. We show that all p-adic representations of these Galois groups are potentially semistable; thus, a conjecture of Fontaine and Mazur on the structure of tamely ramified Galois p-extensions extends to our case. Further evidence in support of this conjecture is presented.", "revisions": [ { "version": "v1", "updated": "2001-12-04T00:00:00.000Z" } ], "analyses": { "keywords": [ "number fields", "wild ramification", "bounded depth", "galois group", "extend well-known properties" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2001math.....12319H" } } }