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Computing modular degrees using L -functions

Christophe Delaunay (2003)

Journal de théorie des nombres de Bordeaux

We give an algorithm to compute the modular degree of an elliptic curve defined over . Our method is based on the computation of the special value at s = 2 of the symmetric square of the L -function attached to the elliptic curve. This method is quite efficient and easy to implement.

Congruent numbers over real number fields

Tomasz Jędrzejak (2012)

Colloquium Mathematicae

It is classical that a natural number n is congruent iff the rank of ℚ -points on Eₙ: y² = x³-n²x is positive. In this paper, following Tada (2001), we consider generalised congruent numbers. We extend the above classical criterion to several infinite families of real number fields.

Constructions de polynômes génériques à groupe de Galois résoluble

Odile Lecacheux (1998)

Acta Arithmetica

On sait que les seuls sous-groupes résolubles transitifs du groupe symétrique ₅ sont isomorphes au groupe de Frobenius 20 , au groupe diédral D₅ et au groupe cyclique C₅. Nous montrerons comment construire des extensions de degré 5 à groupe de Galois résoluble à l’aide de courbes elliptiques. Dans un premier paragraphe nous utiliserons une courbe elliptique ayant un point de 5-torsion rationnel pour les groupes D₅ et C₅. Puis, dans le paragraphe suivant, nous utiliserons une courbe elliptique ayant...

Correspondance

A. Desboves (1879)

Nouvelles annales de mathématiques : journal des candidats aux écoles polytechnique et normale

Counting elliptic curves of bounded Faltings height

Ruthi Hortsch (2016)

Acta Arithmetica

We give an asymptotic formula for the number of elliptic curves over ℚ with bounded Faltings height. Silverman (1986) showed that the Faltings height for elliptic curves over number fields can be expressed in terms of modular functions and the minimal discriminant of the elliptic curve. We use this to recast the problem as one of counting lattice points in a particular region in ℝ².

Critical and ramification points of the modular parametrization of an elliptic curve

Christophe Delaunay (2005)

Journal de Théorie des Nombres de Bordeaux

Let E be an elliptic curve defined over with conductor N and denote by ϕ the modular parametrization: ϕ : X 0 ( N ) E ( ) . In this paper, we are concerned with the critical and ramification points of ϕ . In particular, we explain how we can obtain a more or less experimental study of these points.

Cubic forms, powers of primes and the Kraus method

Andrzej Dąbrowski, Tomasz Jędrzejak, Karolina Krawciów (2012)

Colloquium Mathematicae

We consider the Diophantine equation ( x + y ) ( x ² + B x y + y ² ) = D z p , where B, D are integers (B ≠ ±2, D ≠ 0) and p is a prime >5. We give Kraus type criteria of nonsolvability for this equation (explicitly, for many B and D) in terms of Galois representations and modular forms. We apply these criteria to numerous equations (with B = 0, 1, 3, 4, 5, 6, specific D’s, and p ∈ (10,10⁶)). In the last section we discuss reductions of the above Diophantine equations to those of signature (p,p,2).

Deformations and derived categories

Frauke M. Bleher, Ted Chinburg (2005)

Annales de l'institut Fourier

In this paper we generalize the deformation theory of representations of a profinite group developed by Schlessinger and Mazur to deformations of objects of the derived category of bounded complexes of pseudocompact modules for such a group. We show that such objects have versal deformations under certain natural conditions, and we find a sufficient condition for these versal deformations to be universal. Moreover, we consider applications to deforming Galois cohomology classes and the étale hypercohomology...

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