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arXiv · 2611.08679

Special line bundles on tetragonal curves

Feiyang Lin
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Abstract

One can associate a pair of vector bundles $(E, F)$ on $\mathbb{P}^1$ to every tetragonal curve: $E$ is the Tschirnhausen bundle and $F$ records numerical data of the ideal for the curve under its relative canonical embedding. In this note, we show that a Hurwitz--Brill--Noether general tetragonal curve must have balanced $E$, $F$ bundles, and provide counterexamples for the converse when $g = 8$ or $g \geq 10$.

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Feiyang Lin. 2026-11-05. Special line bundles on tetragonal curves. https://arxiv.org/abs/2611.08679

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