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arXiv · 2609.17344

Poset dimension and maximum comparability degree

Carla Groenland·Richard Montgomery·Rajko Nenadov·Lisa Sauermann
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Abstract

In 1986, Füredi and Kahn showed that the dimension $\dim(P)$ of any finite poset $P$ satisfies $\dim(P) = O(d \log^2 d)$, where $d$ is the maximum degree of the comparability graph of $P$. Scott and Wood more recently improved this bound to one of the form $d \log^{1+o(1)} d$. We show that $\dim(P) = O(d \log d)$, thus confirming that the corresponding lower bound of Erdős, Kierstead, and Trotter is tight up to the implicit constant.

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Carla Groenland, Richard Montgomery, Rajko Nenadov, Lisa Sauermann. 2026-09-15. Poset dimension and maximum comparability degree. https://arxiv.org/abs/2609.17344

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