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arXiv · 1303.5885

Bounds on the diameters of $r$-stacked and $k$-neighborly polytopes

Isabella Novik
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Abstract

We improve Larman's bound on the diameter of a polytope by showing that if $\Delta$ is a normal simplicial complex, all of whose missing faces have size at most $r$, then the diameter of the facet-ridge graph of $\Delta$ is not larger than $2^{r-2}n$, where $n$ is the number of vertices of $\Delta$. We then use this result to provide new upper bounds on the diameters of the facet-ridge graphs of $k$-neighborly spheres, $r$-stacked spheres, and polytopes with small $g_r$. Specifically, our bounds imply that $r$-stacked spheres with $r=O(\log n)$ satisfy the polynomial Hirsch conjecture.

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Isabella Novik. 2013-03-23. Bounds on the diameters of $r$-stacked and $k$-neighborly polytopes. https://arxiv.org/abs/1303.5885

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