A descent method for explicit computations on curves
نویسنده
چکیده مقاله:
It is shown that the knowledge of a surjective morphism $Xto Y$ of complex curves can be effectively used to make explicit calculations. The method is demonstrated by the calculation of $j(ntau)$ (for some small $n$) in terms of $j(tau)$ for the elliptic curve with period lattice $(1,tau)$, the period matrix for the Jacobian of a family of genus-$2$ curves complementing the classic calculations of Bolza and explicit general formulae for branched covers of an elliptic curve with exactly one ramification point.
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عنوان ژورنال
دوره 43 شماره 6
صفحات 1989- 2016
تاریخ انتشار 2017-11-30
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