{ "id": "2005.04556", "version": "v1", "published": "2020-05-10T02:40:21.000Z", "updated": "2020-05-10T02:40:21.000Z", "title": "The treewidth of 2-section of hypergraphs", "authors": [ "Ke Liu", "Mei Lu" ], "categories": [ "math.CO" ], "abstract": "Let $H=(V,F)$ be a simple hypergraph without loops. $H$ is called linear if $|f\\cap g|\\le 1$ for any $f,g\\in F$ with $f\\not=g$. The $2$-section of $H$, denoted by $[H]_2$, is a graph with $V([H]_2)=V$ and for any $ u,v\\in V([H]_2)$, $uv\\in E([H]_2)$ if and only if there is $ f\\in F$ such that $u,v\\in f$. The treewidth of a graph is an important invariant in structural and algorithmic graph theory. In this paper, we consider the treewidth of the $2$-section of a linear hypergraph. We will use the minimum degree, maximum degree, anti-rank and average rank of a linear hypergraph to determine the upper and lower bounds of the treewidth of its $2$-section. Since for any graph $G$, there is a linear hypergraph $H$ such that $[H]_2\\cong G$, we provide a method to estimate the bound of treewidth of graph by the parameters of the hypergraph.", "revisions": [ { "version": "v1", "updated": "2020-05-10T02:40:21.000Z" } ], "analyses": { "keywords": [ "linear hypergraph", "algorithmic graph theory", "simple hypergraph", "important invariant", "minimum degree" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }