2010/07/22 by Sang-il Oum · 1 citation
Mathematics · #math.CO
paper · pdf · doi:10.1016/j.laa.2011.09.027
published as Linear Algebra Appl. 436(April 1, 2012)(7), pp. 2008-2036 · 43 pages
arxiv created 2010/07/22 · arxiv updated 2014/03/26
We prove that every infinite sequence of skew-symmetric or symmetric matrices M1, M2, ... over a fixed finite field must have a pair Mi, Mj (i<j) such that Mi is isomorphic to a principal submatrix of the Schur complement of a nonsingular principal submatrix in Mj, if those matrices have bounded rank-width. This generalizes three theorems on well-quasi-ordering of graphs or matroids admitting good tree-like decompositions; (1) Robertson and Seymour's theorem for graphs of bounded tree-width, (2) Geelen, Gerards, and Whittle's theorem for matroids representable over a fixed finite field having bounded branch-width, and (3) Oum's theorem for graphs of bounded rank-width with respect to pivot-minors.