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arXiv · 1404.6011

A case of the Dynamical Andre-Oort Conjecture

Dragos Ghioca·Holly Krieger·Khoa Nguyen
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Abstract

We prove a special case of the Dynamical Andre-Oort Conjecture formulated by Baker and DeMarco. For any integer d>1, we show that for a rational plane curve C parametrized by (t, h(t)) for some non-constant polynomial h with complex coefficients, if there exist infinitely many points (a,b) on the curve C such that both z^d+a and z^d+b are postcritically finite maps, then h(z)=uz for a (d-1)-st root of unity u. As a by-product of our proof, we show that the Mandelbrot set is not the filled Julia set of any polynomial with complex coefficients.

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Dragos Ghioca, Holly Krieger, Khoa Nguyen. 2014-04-24. A case of the Dynamical Andre-Oort Conjecture. https://arxiv.org/abs/1404.6011

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