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arXiv · 1203.1213

The Fekete-Szego theorem with Local Rationality Conditions on Curves

Robert Rumely
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Abstract

Let $K$ be a number field or a function field in one variable over a finite field, and let $K^{sep}$ be a separable closure of $K$. Let $C/K$ be a smooth, complete, connected curve. We prove a strong theorem of Fekete-Szego type for adelic sets $E = \prod_v E_v$ on $C$, showing that under appropriate conditions there are infinitely many points in $C(K^{sep})$ whose conjugates all belong to $E_v$ at each place $v$ of $K$. We give several variants of the theorem, including two for Berkovich curves, and provide examples illustrating the theorem on the projective line, and on elliptic curves, Fermat curves, and modular curves.

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Robert Rumely. 2012-03-06. The Fekete-Szego theorem with Local Rationality Conditions on Curves. https://arxiv.org/abs/1203.1213

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