Title
Tangles, tree-decompositions and grids in matroids
Abstract
A tangle in a matroid is an obstruction to small branch-width. In particular, the maximum order of a tangle is equal to the branch-width. We prove that: (i) there is a tree-decomposition of a matroid that ''displays'' all of the maximal tangles, and (ii) when M is representable over a finite field, each tangle of sufficiently large order ''dominates'' a large grid-minor. This extends results of Robertson and Seymour concerning Graph Minors.
Year
DOI
Venue
2009
10.1016/j.jctb.2007.10.008
J. Comb. Theory, Ser. B
Keywords
Field
DocType
large grid-minor,matroids,tree-decomposition,branch-width tangles tree-decomposition matroids graph minors,finite field,graph minors,small branch-width,maximum order,branch-width,maximal tangle,tangles,large order,tree decomposition,graph minor
Matroid,Tangle,Discrete mathematics,Graph,Finite field,Combinatorics,Tree decomposition,Matroid partitioning,Graphic matroid,Mathematics,Branch-decomposition
Journal
Volume
Issue
ISSN
99
4
Journal of Combinatorial Theory, Series B
Citations 
PageRank 
References 
11
0.74
6
Authors
3
Name
Order
Citations
PageRank
Jim Geelen124129.49
Bert Gerards214614.47
Geoff Whittle347157.57