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Generators and integer points on the elliptic curve y² = x³ - nx

Yasutsugu Fujita, Nobuhiro Terai (2013)

Acta Arithmetica

Let E be an elliptic curve over the rationals ℚ given by y² = x³ - nx with a positive integer n. We consider first the case where n = N² for a square-free integer N. Then we show that if the Mordell-Weil group E(ℚ ) has rank one, there exist at most 17 integer points on E. Moreover, we show that for some parameterized N a certain point P can be in a system of generators for E(ℚ ), and we determine the integer points in the group generated by the point P and the torsion points. Secondly, we consider...

Generators and integral points on twists of the Fermat cubic

Yasutsugu Fujita, Tadahisa Nara (2015)

Acta Arithmetica

We study integral points and generators on cubic twists of the Fermat cubic curve. The main results assert that integral points can be in a system of generators in the case where the Mordell-Weil rank is at most two. As a corollary, we explicitly describe the integral points on the curve.

Generators for the elliptic curve y 2 = x 3 - n x

Yasutsugu Fujita, Nobuhiro Terai (2011)

Journal de Théorie des Nombres de Bordeaux

Let E be an elliptic curve given by y 2 = x 3 - n x with a positive integer n . Duquesne in 2007 showed that if n = ( 2 k 2 - 2 k + 1 ) ( 18 k 2 + 30 k + 17 ) is square-free with an integer k , then certain two rational points of infinite order can always be in a system of generators for the Mordell-Weil group of E . In this paper, we generalize this result and show that the same is true for infinitely many binary forms n = n ( k , l ) in ℤ [ k , l ] .

Generic Newton polygons of Ekedahl-Oort strata: Oort’s conjecture

Shushi Harashita (2010)

Annales de l’institut Fourier

We study the moduli space of principally polarized abelian varieties in positive characteristic. In this paper we determine the Newton polygon of any generic point of each Ekedahl-Oort stratum, by proving Oort’s conjecture on intersections of Newton polygon strata and Ekedahl-Oort strata. This result tells us a combinatorial algorithm determining the optimal upper bound of the Newton polygons of principally polarized abelian varieties with a given isomorphism type of p -kernel.

Genres de Todd et valeurs aux entiers des dérivées de fonctions L

Christophe Soulé (2005/2006)

Séminaire Bourbaki

La géométrie d’Arakelov étudie les fibrés vectoriels sur une variété algébrique X définie sur les entiers, munis d’une métrique hermitienne lisse sur le fibré holomorphe associé (sur la variété analytique des points complexes de X ). Un théorème de “Riemann-Roch arithmétique” calcule le covolume du réseau euclidien des sections globales d’un tel fibré. Dans cette formule, le genre de Todd comporte un terme complémentaire, défini par une série formelle dont les coefficients font intervenir les valeurs...

Géométrie, points entiers et courbes entières

Pascal Autissier (2009)

Annales scientifiques de l'École Normale Supérieure

Soit X une variété projective sur un corps de nombres K (resp. sur ℂ ). Soit H la somme de « suffisamment de diviseurs positifs » sur X . On montre que tout ensemble de points quasi-entiers (resp. toute courbe entière) dans X - H est non Zariski-dense.

Géométrie réelle des dessins d’enfant : une étude des composantes irréductibles

Layla Pharamond dit d’Costa (2005)

Journal de Théorie des Nombres de Bordeaux

Dans cet article nous nous intéressons aux propriétés des composantes irréductibles associées à la géométrie réelle d’un dessin d’enfant. Plus précisément, nous étudions les composantes irréductibles de la courbe Γ dont l’ensemble des points réels est l’image réciproque de P 1 ( R ) par une fonction de Belyi d’un dessin d’enfant.

Good reduction of elliptic curves over imaginary quadratic fields

Masanari Kida (2001)

Journal de théorie des nombres de Bordeaux

We prove that the j -invariant of an elliptic curve defined over an imaginary quadratic number field having good reduction everywhere satisfies certain Diophantine equations under some hypothesis on the arithmetic of the quadratic field. By solving the Diophantine equations explicitly in the rings of quadratic integers, we show the non-existence of such elliptic curve for certain imaginary quadratic fields. This extends the results due to Setzer and Stroeker.

Greatest common divisors of u - 1 , v - 1 in positive characteristic and rational points on curves over finite fields

Pietro Corvaja, Umberto Zannier (2013)

Journal of the European Mathematical Society

In our previous work we proved a bound for the g c d ( u − 1 , v − 1 ) , for S -units u , v of a function field in characteristic zero. This generalized an analogous bound holding over number fields, proved in [3]. As pointed out by Silverman, the exact analogue does not work for function fields in positive characteristic. In the present work, we investigate possible extensions in that direction; it turns out that under suitable assumptions some of the results still hold. For instance we prove Theorems 2 and 3 below, from...

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