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arXiv · 1808.05018

Brill-Noether Generality of Binary Curves

Xiang He
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Abstract

We show that the space of linear series of certain multi-degree (including the balanced ones) and rank $r$ on a general binary curve has the expected dimension if nonempty. This generalizes Theorem 24 of Caporaso's paper about binary curves from the case $r\leq 2$ to arbitrary rank, and shows that the space of Osserman-limit linear series on a general binary curve has the expected dimension, which was known for $r\leq 2$. In addition, we show that this space of linear series is still of expected dimension after imposing certain ramification conditions with respect to a sequence of increasing effective divisors supported on two general points lying on different components of the curve.

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Xiang He. 2018-08-15. Brill-Noether Generality of Binary Curves. https://doi.org/10.4153/s0008439520000831

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