A moduli interpretation for the non-split Cartan modular curve

Modular curves like X0(N) and X1(N) appear very frequently in arithmetic geometry. While their complex points are obtained as a quotient of the upper half plane by some subgroups of SL2(Z), they allow for a more arithmetic description as a solution to a moduli problem. We wish to give such a moduli...

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Main Authors: Rebolledo, Marusia, Wuthrich, Christian
Format: Article
Published: Cambridge University Press 2018
Online Access:https://eprints.nottingham.ac.uk/43660/
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author Rebolledo, Marusia
Wuthrich, Christian
author_facet Rebolledo, Marusia
Wuthrich, Christian
author_sort Rebolledo, Marusia
building Nottingham Research Data Repository
collection Online Access
description Modular curves like X0(N) and X1(N) appear very frequently in arithmetic geometry. While their complex points are obtained as a quotient of the upper half plane by some subgroups of SL2(Z), they allow for a more arithmetic description as a solution to a moduli problem. We wish to give such a moduli description for two other modular curves, denoted here by Xnsp(p) and X+ nsp(p) associated to non-split Cartan subgroups and their normaliser in GL2(Fp). These modular curves appear for instance in Serre's problem of classifying all possible Galois structures of p-torsion points on elliptic curves over number fields. We give then a moduli-theoretic interpretation and a new proof of a result of Chen [Che98, Che00].
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spelling nottingham-436602020-05-04T19:35:24Z https://eprints.nottingham.ac.uk/43660/ A moduli interpretation for the non-split Cartan modular curve Rebolledo, Marusia Wuthrich, Christian Modular curves like X0(N) and X1(N) appear very frequently in arithmetic geometry. While their complex points are obtained as a quotient of the upper half plane by some subgroups of SL2(Z), they allow for a more arithmetic description as a solution to a moduli problem. We wish to give such a moduli description for two other modular curves, denoted here by Xnsp(p) and X+ nsp(p) associated to non-split Cartan subgroups and their normaliser in GL2(Fp). These modular curves appear for instance in Serre's problem of classifying all possible Galois structures of p-torsion points on elliptic curves over number fields. We give then a moduli-theoretic interpretation and a new proof of a result of Chen [Che98, Che00]. Cambridge University Press 2018-05-01 Article PeerReviewed Rebolledo, Marusia and Wuthrich, Christian (2018) A moduli interpretation for the non-split Cartan modular curve. Glasgow Mathematical Journal, 60 (2). pp. 411-434. ISSN 1469-509X https://www.cambridge.org/core/journals/glasgow-mathematical-journal/article/moduli-interpretation-for-the-nonsplit-cartan-modular-curve/B5C148F18FDB5B33E2470293ECD94D3A doi:10.1017/S0017089517000180 doi:10.1017/S0017089517000180
spellingShingle Rebolledo, Marusia
Wuthrich, Christian
A moduli interpretation for the non-split Cartan modular curve
title A moduli interpretation for the non-split Cartan modular curve
title_full A moduli interpretation for the non-split Cartan modular curve
title_fullStr A moduli interpretation for the non-split Cartan modular curve
title_full_unstemmed A moduli interpretation for the non-split Cartan modular curve
title_short A moduli interpretation for the non-split Cartan modular curve
title_sort moduli interpretation for the non-split cartan modular curve
url https://eprints.nottingham.ac.uk/43660/
https://eprints.nottingham.ac.uk/43660/
https://eprints.nottingham.ac.uk/43660/