Bielliptic modular curves X0* (N)

Let N ≥ 1 be a integer such that the modular curve X0* (N) has genus ≥ 2. We prove that X0* (N) is bielliptic exactly for 69 values of N. In particular, we obtain that X0* (N) is bielliptic over the base field for all these values of N, except X0*(160) that is not bielliptic over Q but it does over...

Descripción completa

Detalles Bibliográficos
Autores: Bars Cortina, Francesc|||0000-0003-4779-3995, González Rovira, Josep
Tipo de recurso: artículo
Fecha de publicación:2020
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:240651
Acceso en línea:https://ddd.uab.cat/record/240651
https://dx.doi.org/urn:doi:10.1016/j.jalgebra.2020.02.028
Access Level:acceso abierto
Palabra clave:Arithmetic geometry
Hyperelliptic curves
Bielliptic curves
Quadratic points
Elliptic curves
Modular curves
Involutions
Descripción
Sumario:Let N ≥ 1 be a integer such that the modular curve X0* (N) has genus ≥ 2. We prove that X0* (N) is bielliptic exactly for 69 values of N. In particular, we obtain that X0* (N) is bielliptic over the base field for all these values of N, except X0*(160) that is not bielliptic over Q but it does over Q(√-1). Moreover, we prove that the set of all quadratic points over Q for the modular curve X0* (N) is infinite exactly for 100 values of N.