Mazur’s rational torsion result for pointless genus one curves: examples

Autor: Arjan Dwarshuis, Majken Roelfszema, Jaap Top
Přispěvatelé: Algebra
Rok vydání: 2021
Předmět:
Zdroj: Research in Number Theory, 7(1):7. Springer Nature
ISSN: 2363-9555
2522-0160
DOI: 10.1007/s40993-020-00231-z
Popis: This note reformulates Mazur’s result on the possible orders of rational torsion points on elliptic curves over$$\mathbb {Q}$$Qin a way that makes sense for arbitrary genus one curves, regardless whether or not the curve contains a rational point. The main result is that explicit examples are provided of ‘pointless’ genus one curves over$$\mathbb {Q}$$Qcorresponding to the torsion orders 7, 8, 9, 10, 12 (and hence, all possibilities) occurring in Mazur’s theorem. In fact three distinct methods are proposed for constructing such examples, each involving different in our opinion quite nice ideas from the arithmetic of elliptic curves or from algebraic geometry.
Databáze: OpenAIRE