2011/02/28 by Archontia C. Giannopoulou, Giannopoulou, Archontia C., Dimitrios M. Thilikos +1 · 1 citation
Computer Science · Engineering · Mathematics · #Advanced Graph Theory Research #Interconnection Networks and Systems #cs.DM #graph theory and CDMA systems #math.CO #msc:05C83
paper · pdf · doi:10.48550/arxiv.1102.5762
arxiv created 2011/02/28 · arxiv updated 2011/03/01
One of the major results of [N. Robertson and P. D. Seymour. Graph minors. XIII. The disjoint paths problem. J. Combin. Theory Ser. B, 63(1):65--110, 1995], also known as the weak structure theorem, revealed the local structure of graphs excluding some graph as a minor: each such graph G either has small treewidth or contains the subdivision of a wall that can be arranged "bidimensionally" inside G, given that some small set of vertices are removed. We prove an optimized version of that theorem where (i) the relation between the treewidth of the graph and the height of the wall is linear (thus best possible) and (ii) the number of vertices to be removed is minimized.