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arXiv · 2007.04062

True trees are dense

Christopher J. Bishop
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Abstract

We show that any compact, connected set $K$ in the plane can be approximated by the critical points of a polynomial with two critical values. Equivalently, $K$ can be approximated in the Hausdorff metric by a true tree in the sense of Grothendieck's dessins d'enfants.

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Christopher J. Bishop. 2020-07-08. True trees are dense. https://doi.org/10.1007/s00222-013-0488-6

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