Graphs and Matroids Seminar - Sang-il Oum
Title: Obstructions for matroids of path-width at most k and graphs of linear rank-width at most k
Speaker: | Sang-il Oum |
Affiliation: | Institute for Basic Science / KAIST |
Zoom: | Join via http://matroidunion.org/?page_id=2477 or please email Shayla Redlin |
Abstract:
Every minor-closed class of matroids of bounded branch-width can be characterized by a minimal list of excluded minors, but unlike graphs, this list could be infinite in general. However, for each fixed finite field $\mathbb F$, the list contains only finitely many $\mathbb F$-representable matroids, due to the well-quasi-ordering of $\mathbb F$-representable matroids of bounded branch-width under taking matroid minors [J. F. Geelen, A. M. H. Gerards, and G. Whittle (2002)].