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arXiv · 1004.4950

Isotropical Linear Spaces and Valuated Delta-Matroids

Felipe Rincón
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Abstract

The spinor variety is cut out by the quadratic Wick relations among the principal Pfaffians of an n x n skew-symmetric matrix. Its points correspond to n-dimensional isotropic subspaces of a 2n-dimensional vector space. In this paper we tropicalize this picture, and we develop a combinatorial theory of tropical Wick vectors and tropical linear spaces that are tropically isotropic. We characterize tropical Wick vectors in terms of subdivisions of Delta-matroid polytopes, and we examine to what extent the Wick relations form a tropical basis. Our theory generalizes several results for tropical linear spaces and valuated matroids to the class of Coxeter matroids of type D.

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BibTeXRIS

Felipe Rincón. 2010-04-28. Isotropical Linear Spaces and Valuated Delta-Matroids. https://doi.org/10.1016/j.jcta.2011.08.001

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