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arXiv · 2112.08437

Facet volumes of polytopes

Pavle V. M. Blagojević·Paul Breiding·Alexander Heaton
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Abstract

In this paper, motivated by the work of Edelman and Strang, we show that for fixed integers $d\geq 2$ and $n\geq d+1$ the configuration space of all facet volume vectors of all $d$-polytopes in $\mathbb R^{d}$ with $n$ facets is a full dimensional cone in $\mathbb R^{n}$. In particular, for tetrahedra ($d=3$ and $n=4$) this is a cone over a regular octahedron. Our proof is based on a novel configuration space / test map scheme which uses topological methods for finding solutions of a problem, and tools of differential geometry to identify solutions with the desired properties. Furthermore, our results open a possibility for the study of realization spaces of all $d$-polytopes in $\mathbb R^{d}$ with $n$ facets by the methods of algebraic topology.

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BibTeXRIS

Pavle V. M. Blagojević, Paul Breiding, Alexander Heaton. 2021-12-15. Facet volumes of polytopes. https://arxiv.org/abs/2112.08437

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