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arXiv · 2503.22490

Graphs generated from minimal sets of finite point-set topologies

Abstract

In 1985, Golumbic and Scheinerman established an equivalence between comparability graphs and containment graphs, graphs whose vertices represent sets, with edges indicating set containment. A few years earlier, McMorris and Zaslavsky characterized upper bound graphs, those derived from partially ordered sets where two elements share an edge if they have a common upper bound, by a specific edge clique cover condition. In this paper, we introduce a unifying framework for these results using finite point set topologies. Given a finite topology, we define a graph whose vertices correspond to its elements, with edges determined by intersections of their minimal containing sets, where intersection is understood in terms of the topological separation axioms. This construction yields a natural sequence of graph classes, one for each separation axiom, that connects and extends both classical results in a structured and intuitive way.

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BibTeXRIS

Ketai Chen, Jared DeLeo, Owen Henderschedt. 2025-03-28. Graphs generated from minimal sets of finite point-set topologies. https://arxiv.org/abs/2503.22490

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