Models for quotients of modular curves

2021/01/11 by Josha Box, Box, Josha
Mathematics · #Advanced Algebra and Geometry #Algebraic Geometry and Number Theory #Mathematical Analysis and Transform Methods #math.NT #msc:11F11 #msc:11G18

paper · pdf · doi:10.48550/arxiv.2101.03797

arxiv created 2021/07/12 · arxiv updated 2021/07/13

Abstract

We describe an algorithm for computing a \Q-rational model for the quotient of a modular curve by an automorphism group, under mild assumptions on the curve and the automorphisms, by determining q-expansions for a basis of the corresponding space of cusp forms. We also give a moduli interpretation for general morphisms between modular curves.

Related

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