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arXiv · 1004.2403

K-classes of matroids and equivariant localization

Alex Fink·David E Speyer
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Abstract

To every matroid, we associate a class in the K-theory of the Grassmannian. We study this class using the method of equivariant localization. In particular, we provide a geometric interpretation of the Tutte polynomial. We also extend results of the second author concerning the behavior of such classes under direct sum, series and parallel connection and two-sum; these results were previously only established for realizable matroids, and their earlier proofs were more difficult.

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Alex Fink, David E Speyer. 2010-08-26. K-classes of matroids and equivariant localization. https://doi.org/10.1215/00127094-1813296

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