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arXiv · 0908.1741

Minimisation and reduction of 2-, 3- and 4-coverings of elliptic curves

John Cremona·Tom Fisher·Michael Stoll
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Abstract

In this paper we consider models for genus one curves of degree n for n = 2, 3 and 4, which arise in explicit n-descent on elliptic curves. We prove theorems on the existence of minimal models with the same invariants as the minimal model of the Jacobian elliptic curve and provide simple algorithms for minimising a given model, valid over general number fields. Finally, for genus one models defined over Q, we develop a theory of reduction and again give explicit algorithms for n = 2, 3 and 4.

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John Cremona, Tom Fisher, Michael Stoll. 2009-08-12. Minimisation and reduction of 2-, 3- and 4-coverings of elliptic curves. https://doi.org/10.2140/ant.2010.4.763

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