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arXiv · 1910.12898

Expanding metrics for unicritical semihyperbolic polynomials

Lukas Geyer
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Abstract

We prove that unicritical polynomials $f(z)=z^d+c$ which are semihyperbolic, i.e., for which the critical point $0$ is a non-recurrent point in the Julia set, are uniformly expanding on the Julia set with respect to the metric $\rho(z) |dz|$, where $\rho(z) = 1+\frac{1}{\textrm{dist}(z,P(f))^{1-1/d}}$, and where $P(f)$ is the postcritical set of $f$. We also show that this metric is H\"older equivalent to the usual Euclidean metric.

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Lukas Geyer. 2019-10-28. Expanding metrics for unicritical semihyperbolic polynomials. https://arxiv.org/abs/1910.12898

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