Complexes of nearly maximum diameter

Tom Bohman; Andrew Newman

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arXiv · 2204.11932

Complexes of nearly maximum diameter

Tom Bohman·Andrew Newman

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Abstract

The diameter of a strongly connected $d$-dimensional simplicial complex is the diameter of its dual graph. We provide a probabilistic proof of the existence of $d$-dimensional simplicial complexes with diameter $ (\frac{1}{d \cdot d!} - (\log n)^{-\epsilon}) n^d$. Up to the first order term, this is the best possible lower bound for the maximum diameter of a $d$-complex on $n$ vertices as a simple volume argument shows that the diameter of a $d$-dimensional simplicial complex is at most $ \frac{1}{d} \binom{n}{d}$. We also find the right first-order asymptotics for the maximum diameter of a $d$-pseudomanifold on $n$ vertices.

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Tom Bohman, Andrew Newman. 2022-04-25. Complexes of nearly maximum diameter. https://arxiv.org/abs/2204.11932

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