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arXiv · 2409.05796

Large degree primitive points on curves

Maarten Derickx
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Abstract

A number field $K$ is called primitive if $\mathbb Q$ and $K$ are the only subfields of $K$. Let $X$ be a nice curve over $\mathbb Q$ of genus $g$. A point $P$ of degree $d$ on $X$ is called primitive if the field of definition $\mathbb Q(P)$ of the point is primitive. In this short note we prove that if $X$ has a divisor of degree $d> 2g$, then $X$ has infinitely many primitive points of degree $d$. This complements the results of Khawaja and Siksek that show that points of low degree are not primitive under certain conditions.

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Maarten Derickx. 2024-09-09. Large degree primitive points on curves. https://arxiv.org/abs/2409.05796

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