Ramification in Local Galois Groups-the Second Central Step
نویسندگان
چکیده
منابع مشابه
Galois Groups of Local Fields, Lie Algebras and Ramification
Suppose K is a local field with finite residue field of characteristic p 6= 2 and K<p(M) is its maximal p-extension such that Gal(K<p(M)/K) has period p M and nilpotent class < p. If charK = 0 we assume that K contains a primitive p -th root of unity. The paper contains an overview of methods and results describing the structure of this Galois group together with its filtration by ramification ...
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We recall the definition and basic properties of ramification groups. We compute it in the most elementary cases. One is the classical case, i.e., the case where the residue field is perfect. The other is the abelian and the equal characterictic case. Plan 1. Ramification groups. 2. Classical case. 3. Rank 1 case. (Possible) Applications. 1. Grothendieck-Ogg-Shafarevich formula, conductor formu...
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Let p be an odd prime number and F a field containing a primitive pth root of unity. We prove a new restriction on the group-theoretic structure of the absolute Galois group GF of F . Namely, the third subgroup G (3) F in the descending p-central sequence of GF is the intersection of all open normal subgroups N such that GF /N is 1, Z/p , or the modular group Mp3 of order p .
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ژورنال
عنوان ژورنال: Pure and Applied Mathematics Quarterly
سال: 2009
ISSN: 1558-8599,1558-8602
DOI: 10.4310/pamq.2009.v5.n1.a9