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arXiv · 2107.06358

Ramification loci of non-archimedean cubic rational functions

Reimi Irokawa
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Abstract

For a cubic rational function with coefficients in a non-archimedean field $K$ whose residue characteristic is $0$ or greater than $3$, there are $2$ possibilities for the shape of its Berkovich ramification locus, considered as an endomorphism of the Berkovich projective line: one is the connected hull of all the critical points, and the other is consisting of $2$ disjoint segments. In this paper, we list up all the possible forms of cubic rational functions and calculate their ramification loci.

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Reimi Irokawa. 2021-07-13. Ramification loci of non-archimedean cubic rational functions. https://arxiv.org/abs/2107.06358

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