{ "id": "2109.06269", "version": "v1", "published": "2021-09-13T19:13:01.000Z", "updated": "2021-09-13T19:13:01.000Z", "title": "A bound for the $p$-domination number of a graph in terms of its eigenvalue multiplicities", "authors": [ "A. Abiad", "S. Akbari", "M. H. Fakharan", "A. Mehdizadeh" ], "categories": [ "math.CO" ], "abstract": "Let $G$ be a connected graph of order $n$ with domination number $\\gamma(G)$. Wang, Yan, Fang, Geng and Tian [Linear Algebra Appl. 607 (2020), 307-318] showed that for any Laplacian eigenvalue $\\lambda$ of $G$ with multiplicity $m_G(\\lambda)$, it holds that $\\gamma(G)\\leq n-m_G(\\lambda)$. Using techniques from the theory of star sets, in this work we prove that the same bound holds when $\\lambda$ is an arbitrary adjacency eigenvalue of a non-regular graph, and we characterize the cases of equality. Moreover, we show a result that gives a relationship between start sets and the $p$-domination number, and we apply it to extend the aforementioned spectral bound to the $p$-domination number using the adjacency and Laplacian eigenvalue multiplicities.", "revisions": [ { "version": "v1", "updated": "2021-09-13T19:13:01.000Z" } ], "analyses": { "keywords": [ "domination number", "multiplicity", "arbitrary adjacency eigenvalue", "laplacian eigenvalue multiplicities", "linear algebra appl" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }