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Intersection de courbes et de sous-groupes et problèmes de minoration de hauteur dans les variétés abéliennes C.M.

Nicolas Ratazzi (2008)

Annales de l’institut Fourier

Nous prouvons un cas particulier de la conjecture suivante e Zilber-Pink, conjecture généralisant celle de Manin-Mumford  : soit X une courbe incluse dans une variété abélienne A sur ¯ , qui n’est pas incluse dans une sous-variété de torsion  ; l’intersection de X avec la réunion de tous les sous-groupes de codimension au moins 2 est finie. Nous démontrons ici le cas où A est une puissance d’une variété abélienne C.M. simple. La preuve reprend la stratégie de Rémond (suivant Bombieri-Masser-Zannier)...

Non-existence of points rational over number fields on Shimura curves

Keisuke Arai (2016)

Acta Arithmetica

Jordan, Rotger and de Vera-Piquero proved that Shimura curves have no points rational over imaginary quadratic fields under a certain assumption. In this article, we extend their results to the case of number fields of higher degree. We also give counterexamples to the Hasse principle on Shimura curves.

Non-trivial Ш in the Jacobian of an infinite family of curves of genus 2

Anna Arnth-Jensen, E. Victor Flynn (2009)

Journal de Théorie des Nombres de Bordeaux

We give an infinite family of curves of genus 2 whose Jacobians have non-trivial members of the Tate-Shafarevich group for descent via Richelot isogeny. We prove this by performing a descent via Richelot isogeny and a complete 2-descent on the isogenous Jacobian. We also give an explicit model of an associated family of surfaces which violate the Hasse principle.

On cohomological systems of Galois representations

Wojciech Gajda, Sebastian Petersen (2016)

Banach Center Publications

The paper contains an expanded version of the talk delivered by the first author during the conference ALANT3 in Będlewo in June 2014. We survey recent results on independence of systems of Galois representations attached to ℓ-adic cohomology of schemes. Some other topics ranging from the Mumford-Tate conjecture and the Geyer-Jarden conjecture to applications of geometric class field theory are also considered. In addition, we have highlighted a variety of open questions which can lead to interesting...

On component groups of Jacobians of Drinfeld modular curves

Mihran Papikian (2004)

Annales de l'Institut Fourier

Let J 0 ( 𝔫 ) be the Jacobian variety of the Drinfeld modular curve X 0 ( 𝔫 ) over 𝔽 q ( t ) , where 𝔫 is an ideal in 𝔽 q [ t ] . Let 0 B J 0 ( 𝔫 ) A 0 be an exact sequence of abelian varieties. Assume B , as a subvariety of J 0 ( 𝔫 ) , is stable under the action of the Hecke algebra 𝕋 End ( J 0 ( 𝔫 ) ) . We give a criterion which is sufficient for the exactness of the induced sequence of component groups 0 Φ B , Φ J , Φ A , 0 of the Néron models of these abelian varieties over 𝔽 q [ [ 1 t ] ] . This criterion is always satisfied when either A or B is one-dimensional. Moreover, we prove that the sequence...

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