On the modularity level of modular abelian varieties over number fields

Let $f$ be a weight two newform for $\Gamma_1(N)$ without complex multiplication. In this article we study the conductor of the absolutely simple factors $B$ of the variety $A_f$ over certain number fields $L$. The strategy we follow is to compute the restriction of scalars $\operatorname{Res}_{L /...

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Bibliographic Details
Authors: González-Jiménez, Enrique, Guitart Morales, Xavier
Format: article
Status:Versión aceptada para publicación
Publication Date:2010
Country:España
Institution:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repository:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:2445/193362
Online Access:https://hdl.handle.net/2445/193362
Access Level:Open access
Keyword:Teoria de nombres
Varietats abelianes
Geometria algebraica
Varietats de Shimura
Number theory
Abelian varieties
Algebraic geometry
Shimura varieties
Description
Summary:Let $f$ be a weight two newform for $\Gamma_1(N)$ without complex multiplication. In this article we study the conductor of the absolutely simple factors $B$ of the variety $A_f$ over certain number fields $L$. The strategy we follow is to compute the restriction of scalars $\operatorname{Res}_{L / Q}(B)$, and then to apply Milne's formula for the conductor of the restriction of scalars. In this way we obtain an expression for the local exponents of the conductor $\mathcal{N}_L(B)$. Under some hypothesis it is possible to give global formulas relating this conductor with $N$. For instance, if $N$ is squarefree we find that $\mathcal{N}_L(B)$ belongs to $\mathbb{Z}$ and $\mathcal{N}_L(B) \mathfrak{f}_L^{\operatorname{dim} B}=N^{\operatorname{dim} B}$, where $\mathfrak{f}_L$ is the conductor of $L$.