Alberto Espuny Díaz, Lyuben Lichev, Dieter Mitsche, Alexandra Wesolek
{"title":"Sharp threshold for embedding balanced spanning trees in random geometric graphs","authors":"Alberto Espuny Díaz, Lyuben Lichev, Dieter Mitsche, Alexandra Wesolek","doi":"10.1002/jgt.23106","DOIUrl":null,"url":null,"abstract":"<p>A rooted tree is <i>balanced</i> if the degree of a vertex depends only on its distance to the root. In this paper we determine the sharp threshold for the appearance of a large family of balanced spanning trees in the random geometric graph <span></span><math>\n <semantics>\n <mrow>\n <mi>G</mi>\n <mrow>\n <mo>(</mo>\n <mrow>\n <mi>n</mi>\n <mo>,</mo>\n <mi>r</mi>\n <mo>,</mo>\n <mi>d</mi>\n </mrow>\n <mo>)</mo>\n </mrow>\n </mrow>\n <annotation> ${\\mathscr{G}}(n,r,d)$</annotation>\n </semantics></math>. In particular, we find the sharp threshold for balanced binary trees. More generally, we show that <i>all</i> sequences of balanced trees with uniformly bounded degrees and height tending to infinity appear above a sharp threshold, and none of these appears below the same value. Our results hold more generally for geometric graphs satisfying a mild condition on the distribution of their vertex set, and we provide a polynomial time algorithm to find such trees.</p>","PeriodicalId":16014,"journal":{"name":"Journal of Graph Theory","volume":"107 1","pages":"107-125"},"PeriodicalIF":0.9000,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Graph Theory","FirstCategoryId":"100","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1002/jgt.23106","RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATHEMATICS","Score":null,"Total":0}
引用次数: 0
Abstract
A rooted tree is balanced if the degree of a vertex depends only on its distance to the root. In this paper we determine the sharp threshold for the appearance of a large family of balanced spanning trees in the random geometric graph . In particular, we find the sharp threshold for balanced binary trees. More generally, we show that all sequences of balanced trees with uniformly bounded degrees and height tending to infinity appear above a sharp threshold, and none of these appears below the same value. Our results hold more generally for geometric graphs satisfying a mild condition on the distribution of their vertex set, and we provide a polynomial time algorithm to find such trees.
期刊介绍:
The Journal of Graph Theory is devoted to a variety of topics in graph theory, such as structural results about graphs, graph algorithms with theoretical emphasis, and discrete optimization on graphs. The scope of the journal also includes related areas in combinatorics and the interaction of graph theory with other mathematical sciences.
A subscription to the Journal of Graph Theory includes a subscription to the Journal of Combinatorial Designs .