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arXiv · 2111.05880

Generalized Tevelev degrees of $\mathbb{P}^1$

Alessio Cela·Carl Lian
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Abstract

Let $(C,p_1,\ldots,p_n)$ be a general curve. We consider the problem of enumerating covers of the projective line by $C$ subject to incidence conditions at the marked points. These counts have been obtained by the first named author with Pandharipande and Schmitt via intersection theory on Hurwitz spaces and by the second named author with Farkas via limit linear series. In this paper, we build on these two approaches to generalize these counts to the situation where the covers are constrained to have arbitrary ramification profiles: that is, additional ramification conditions are imposed at the marked points, and some collections of marked points are constrained to have equal image.

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Alessio Cela, Carl Lian. 2021-11-10. Generalized Tevelev degrees of $\mathbb{P}^1$. https://arxiv.org/abs/2111.05880

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