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arXiv · 1507.03535

Configuration of the Crucial Set for a Quadratic Rational Map

John R. Doyle·Kenneth Jacobs·Robert Rumely
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Abstract

Let $K$ be a complete, algebraically closed non-archimedean valued field, and let $\varphi(z) \in K(z)$ have degree two. We describe the crucial set of $\varphi$ in terms of the multipliers of $\varphi$ at the classical fixed points, and use this to show that the crucial set determines a stratification of the moduli space $\mathcal{M}_2(K)$ related to the reduction type of $\varphi$. We apply this to settle a special case of a conjecture of Hsia regarding the density of repelling periodic points in the non-archimedean Julia set.

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John R. Doyle, Kenneth Jacobs, Robert Rumely. 2015-07-13. Configuration of the Crucial Set for a Quadratic Rational Map. https://arxiv.org/abs/1507.03535

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