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2014 | OriginalPaper | Chapter

Unifying Duality Theorems for Width Parameters in Graphs and Matroids (Extended Abstract)

Authors : Reinhard Diestel, Sang-il Oum

Published in: Graph-Theoretic Concepts in Computer Science

Publisher: Springer International Publishing

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Abstract

We prove a general duality theorem for width parameters in combinatorial structures such as graphs and matroids. It implies the classical such theorems for path-width, tree-width, branch-width and rank-width, and gives rise to new width parameters with associated duality theorems. The dense substructures witnessing large width are presented in a unified way akin to tangles, as orientations of separation systems satisfying certain consistency axioms.

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Footnotes
1
In fact, we need even less. It would be enough to consider instead of ‘separations’ any poset with an involution that commutes with its ordering, just as the ordering of separations introduced below satisfies \((A,B)\le (C,D) \Leftrightarrow (B,A)\ge (D,C)\). It is only for the sake of readability that we are writing this paper in terms of separations, as readers are likely to have graphs or matroids in mind.
 
2
Our notational convention will be that we think of \((A,B)\) as pointing towards \(B\).
 
3
It is a good idea to work with this formal definition of consistency, since the more intuitive notion of ‘pointing away from each other’ can be counterintuitive. For example, we shall need that no consistent set of separations of \(V\) contains a separation of the form \((V,A)\); this follows readily from the formal definition, as \((A,V)\le (V,A)\), but is less obvious from the informal.
 
4
This will help us show that \((T,\alpha ')\) is over \(\mathcal F\) if \((T,\alpha )\) is.
 
5
This will help us show that \((T,\alpha ')\) is rooted in \(S^-\) if \((T,\alpha )\) is.
 
6
For example, we do not need Menger’s theorem, as all the other proofs do.
 
7
In our matroid terminology we follow Oxley [9].
 
Literature
1.
go back to reference Amini, O., Mazoit, F., Nisse, N., Thomassé, S.: Submodular partition functions. Discrete Appl. Math. 309(20), 6000–6008 (2009)CrossRefMATH Amini, O., Mazoit, F., Nisse, N., Thomassé, S.: Submodular partition functions. Discrete Appl. Math. 309(20), 6000–6008 (2009)CrossRefMATH
2.
go back to reference Bienstock, D., Robertson, N., Seymour, P., Thomas, R.: Quickly excluding a forest. J. Combin. Theor. Ser. B 52(2), 274–283 (1991)MathSciNetCrossRefMATH Bienstock, D., Robertson, N., Seymour, P., Thomas, R.: Quickly excluding a forest. J. Combin. Theor. Ser. B 52(2), 274–283 (1991)MathSciNetCrossRefMATH
4.
go back to reference Geelen, J., Gerards, B., Robertson, N., Whittle, G.: Obstructions to branch-decomposition of matroids. J. Combin. Theor. Ser. B 96, 560–570 (2006)MathSciNetCrossRefMATH Geelen, J., Gerards, B., Robertson, N., Whittle, G.: Obstructions to branch-decomposition of matroids. J. Combin. Theor. Ser. B 96, 560–570 (2006)MathSciNetCrossRefMATH
9.
go back to reference Oxley, J.: Matroid Theory. Oxford University Press, Oxford (1992)MATH Oxley, J.: Matroid Theory. Oxford University Press, Oxford (1992)MATH
10.
11.
Metadata
Title
Unifying Duality Theorems for Width Parameters in Graphs and Matroids (Extended Abstract)
Authors
Reinhard Diestel
Sang-il Oum
Copyright Year
2014
DOI
https://doi.org/10.1007/978-3-319-12340-0_1

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