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arXiv · 1807.02605

Numerical computation of endomorphism rings

Nils Bruin·Jeroen Sijsling·Alexandre Zotine
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Abstract

We give practical numerical methods to compute the period matrix of a plane algebraic curve (not necessarily smooth). We show how automorphisms and isomorphisms of such curves, as well as the decomposition of their Jacobians up to isogeny, can be calculated heuristically. Particular applications include the determination of (generically) non-Galois morphisms between curves and the identification of Prym varieties.

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Nils Bruin, Jeroen Sijsling, Alexandre Zotine. 2018-07-07. Numerical computation of endomorphism rings. https://doi.org/10.2140/obs.2019.2.155

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