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arXiv · 1612.08670

Diagrams and essential sets for signed permutations

David Anderson
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Abstract

We introduce diagrams and essential sets for signed permutations, extending the analogous notions for ordinary permutations. In particular, we show that the essential set provides a minimal list of rank conditions defining the Schubert variety or degeneracy locus corresponding to a signed permutation. Our essential set is in bijection with the poset-theoretic version defined by Reiner, Woo, and Yong, and thus gives an explicit, diagrammatic method for computing the latter.

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David Anderson. 2016-12-27. Diagrams and essential sets for signed permutations. https://arxiv.org/abs/1612.08670

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