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arXiv · 1710.10524

Interlacement and Activities in Delta-Matroids

Ada Morse
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Abstract

We generalize theories of graph, matroid, and ribbon-graph activities to delta-matroids. As a result, we obtain an activities based feasible-set expansion for a transition polynomial of delta-matroids defined by Brijder and Hoogeboom. This result yields feasible-set expansions for the two-variable Bollobás-Riordan and interlace polynomials of a delta-matroid. In the former case, the expansion obtained directly generalizes the activities expansions of the Tutte polynomial of graphs and matroids.

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Ada Morse. 2017-10-28. Interlacement and Activities in Delta-Matroids. https://arxiv.org/abs/1710.10524

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