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Drinfeld modular curves have many points

Lenny Taelman
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Abstract

Ihara's proof that the reduction of the modular curve $X_0(n)$ at a prime $p$ not dividing $n$ has many points over a quadratic extension is adapted to the drinfeld modular curves $X_0(n)$. In order to do so, some properties of drinfeld modular varieties that have no proof in the literature are proven. The text is more or less self-contained.

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Lenny Taelman. 2006-02-08. Drinfeld modular curves have many points. https://arxiv.org/abs/math/0602157

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