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Skew-symmetric Vanishing Lattices and Intersections of Schubert Cells

B. Shapiro·M. Shapiro·A. Vainshtein
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Abstract

We prove that the number of connected components in the intersection of two open opposite Schubert cells in the variety of complete real n-dimensional flags equals 3*2^{n-1} for n>5.

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B. Shapiro, M. Shapiro, A. Vainshtein. 1998-02-19. Skew-symmetric Vanishing Lattices and Intersections of Schubert Cells. https://arxiv.org/abs/math/9802093

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