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arXiv · 1411.6639

Functions and differentials on the non-split Cartan modular curve of level 11

Julio Fernández·Josep González
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Abstract

The genus $4$ modular curve $X_{ns}(11)$ attached to a non-split Cartan group of level $11$ admits a model defined over $\mathbb{Q}$. We compute generators for its function field in terms of Siegel modular functions. We also show that its Jacobian is isomorphic over $\mathbb{Q}$ to the new part of the Jacobian of the classical modular curve $X_0(121)$.

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Julio Fernández, Josep González. 2014-11-24. Functions and differentials on the non-split Cartan modular curve of level 11. https://arxiv.org/abs/1411.6639

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