True trees are dense
arXiv:2007.04062 · doi:10.1007/s00222-013-0488-6
Abstract
We show that any compact, connected set in the plane can be approximated by the critical points of a polynomial with two critical values. Equivalently, can be approximated in the Hausdorff metric by a true tree in the sense of Grothendieck's dessins d'enfants.
25 pages, 15 figures