Directed trees in a string, real polynomials with triple roots, and chain mails

Dmitry N. Kozlov

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arXiv · math/0210045

Directed trees in a string, real polynomials with triple roots, and chain mails

Dmitry N. Kozlov

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Abstract

This paper starts with an observation that two infinite series of simplicial complexes, which a priori do not seem to have anything to do with each other, have the same homotopy type. One series consists of the complexes of directed forests on a double directed string, while the other one consists of Shapiro-Welker models for the spaces of hyperbolic polynomials with a triple root. We explain this coincidence in the more general context by finding an explicit homotopy equivalence between complexes of directed forests on a double directed tree, and doubly disconnecting complexes of a tree.

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Dmitry N. Kozlov. 2002-10-03. Directed trees in a string, real polynomials with triple roots, and chain mails. https://arxiv.org/abs/math/0210045

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