Uniform semimodular lattices and valuated matroids

Hiroshi Hirai

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arXiv · 1802.08809

Uniform semimodular lattices and valuated matroids

Hiroshi Hirai

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Abstract

In this paper, we present a lattice-theoretic characterization for valuated matroids, which is an extension of the well-known cryptomorphic equivalence between matroids and geometric lattices ($=$ atomistic semimodular lattices). We introduce a class of semimodular lattices, called uniform semimodular lattices, and establish a cryptomorphic equivalence between integer-valued valuated matroids and uniform semimodular lattices. Our result includes a coordinate-free lattice-theoretic characterization of integer points in tropical linear spaces, incorporates the Dress-Terhalle completion process of valuated matroids, and establishes a smooth connection with Euclidean buildings of type A.

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Hiroshi Hirai. 2018-02-24. Uniform semimodular lattices and valuated matroids. https://arxiv.org/abs/1802.08809

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