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Regulators of rank one quadratic twists

Christophe Delaunay, Xavier-François Roblot (2008)

Journal de Théorie des Nombres de Bordeaux

We investigate the regulators of elliptic curves with rank 1 in some families of quadratic twists of a fixed elliptic curve. In particular, we formulate some conjectures on the average size of these regulators. We also describe an efficient algorithm to compute explicitly some of the invariants of a rank one quadratic twist of an elliptic curve (regulator, order of the Tate-Shafarevich group, etc.) and we discuss the numerical data that we obtain and compare it with our predictions.

Relations between jacobians of modular curves of level p 2

Imin Chen, Bart De Smit, Martin Grabitz (2004)

Journal de Théorie des Nombres de Bordeaux

We derive a relation between induced representations on the group GL 2 ( / p 2 ) which implies a relation between the jacobians of certain modular curves of level p 2 . The motivation for the construction of this relation is the determination of the applicability of Mazur’s method to the modular curve associated to the normalizer of a non-split Cartan subgroup of GL 2 ( / p 2 ) .

Relative Bogomolov extensions

Robert Grizzard (2015)

Acta Arithmetica

A subfield K ⊆ ℚ̅ has the Bogomolov property if there exists a positive ε such that no non-torsion point of K × has absolute logarithmic height below ε. We define a relative extension L/K to be Bogomolov if this holds for points of L × K × . We construct various examples of extensions which are and are not Bogomolov. We prove a ramification criterion for this property, and use it to show that such extensions can always be constructed if some rational prime has bounded ramification index in K.

Remarks on strongly modular Jacobian surfaces

Xavier Guitart, Jordi Quer (2011)

Journal de Théorie des Nombres de Bordeaux

In [3] we introduced the concept of strongly modular abelian variety. This note contains some remarks and examples of this kind of varieties, especially for the case of Jacobian surfaces, that complement the results of [3].

Remarques sur une conjecture de Lang

Fabien Pazuki (2010)

Journal de Théorie des Nombres de Bordeaux

Le but de cet article est d’étudier une conjecture de Lang énoncée sur les courbes elliptiques dans un livre de Serge Lang, puis généralisée aux variétés abéliennes de dimension supérieure dans un article de Joseph Silverman. On donne un résultat asymptotique sur la hauteur des points de Heegner sur J 0 ( N ) , lequel permet de déduire que la conjecture est optimale dans sa formulation.

Rigid cohomology and p -adic point counting

Alan G.B. Lauder (2005)

Journal de Théorie des Nombres de Bordeaux

I discuss some algorithms for computing the zeta function of an algebraic variety over a finite field which are based upon rigid cohomology. Two distinct approaches are illustrated with a worked example.

S -integral points on elliptic curves - Notes on a paper of B. M. M. de Weger

Emanuel Herrmann, Attila Pethö (2001)

Journal de théorie des nombres de Bordeaux

In this paper we give a much shorter proof for a result of B.M.M de Weger. For this purpose we use the theory of linear forms in complex and p -adic elliptic logarithms. To obtain an upper bound for these linear forms we compare the results of Hajdu and Herendi and Rémond and Urfels.

S -integral solutions to a Weierstrass equation

Benjamin M. M. de Weger (1997)

Journal de théorie des nombres de Bordeaux

The rational solutions with as denominators powers of 2 to the elliptic diophantine equation y 2 = x 3 - 228 x + 848 are determined. An idea of Yuri Bilu is applied, which avoids Thue and Thue-Mahler equations, and deduces four-term ( S -) unit equations with special properties, that are solved by linear forms in real and p -adic logarithms.

Selmer groups for elliptic curves in l d -extensions of function fields of characteristic p

Andrea Bandini, Ignazio Longhi (2009)

Annales de l’institut Fourier

Let F be a function field of characteristic p > 0 , / F a l d -extension (for some prime l p ) and E / F a non-isotrivial elliptic curve. We study the behaviour of the r -parts of the Selmer groups ( r any prime) in the subextensions of via appropriate versions of Mazur’s Control Theorem. As a consequence we prove that the limit of the Selmer groups is a cofinitely generated (in some cases cotorsion) module over the Iwasawa algebra of / F .

Semistable reduction and torsion subgroups of abelian varieties

Alice Silverberg, Yuri G. Zarhin (1995)

Annales de l'institut Fourier

The main result of this paper implies that if an abelian variety over a field F has a maximal isotropic subgroup of n -torsion points all of which are defined over F , and n 5 , then the abelian variety has semistable reduction away from n . This result can be viewed as an extension of Raynaud’s theorem that if an abelian variety and all its n -torsion points are defined over a field F and n 3 , then the abelian variety has semistable reduction away from n . We also give information about the Néron models...

Set of Points on Elliptic Curve in Projective Coordinates

Yuichi Futa, Hiroyuki Okazaki, Yasunari Shidama (2011)

Formalized Mathematics

In this article, we formalize a set of points on an elliptic curve over GF(p). Elliptic curve cryptography [10], whose security is based on a difficulty of discrete logarithm problem of elliptic curves, is important for information security.

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