1. Upper bounds on L (1, χ ) taking into account ramified prime ideals
- Author
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Stéphane Louboutin, Institut de Mathématiques de Marseille (I2M), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU)
- Subjects
Discrete mathematics ,Dedekind zeta function ,Algebra and Number Theory ,L-function ,11R42 (11M20) ,010102 general mathematics ,Residues ,Algebraic number field ,01 natural sciences ,Prime (order theory) ,[MATH.MATH-NT]Mathematics [math]/Number Theory [math.NT] ,Conductor ,Character (mathematics) ,Quadratic equation ,0103 physical sciences ,Ray class group ,010307 mathematical physics ,0101 mathematics ,Abelian group ,Number field ,Mathematics - Abstract
Let χ range over the non-trivial primitive characters associated with the abelian extensions L / K of a given number field K , i.e. over the non-trivial primitive characters on ray class groups of K . Let f χ be the norm of the finite part of the conductor of such a character. It is known that | L ( 1 , χ ) | ≤ 1 2 Res s = 1 ( ζ K ( s ) ) log f χ + O ( 1 ) , where the implied constants in this O ( 1 ) are effective and depend on K only. The proof of this result suggests that one can expect better upper bounds by taking into account prime ideals of K dividing the conductor of χ, i.e. ramified prime ideals. This has already been done only in the case that K = Q . This paper is devoted to giving for the first time such improvements for any K . As a non-trivial example, we give fully explicit bounds when K is an imaginary quadratic number field.
- Published
- 2017