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arXiv · 1810.13159

Sects

Aram Bingham·Mahir Bilen Can
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Abstract

By explicitly describing a cellular decomposition we determine the Borel invariant cycles that generate the Chow groups of the quotient of a reductive group by a Levi subgroup. For illustrations we consider the variety of polarizations $\mbf{SL}_n / \mbf{S}(\mbf{GL}_p\times \mbf{GL}_q)$, and we introduce the notion of a sect for describing its cellular decomposition. In particular, for $p=q$, we show that the Bruhat order on the sect corresponding to the dense cell is isomorphic, as a poset, to the rook monoid with the Bruhat-Chevalley-Renner order.

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Aram Bingham, Mahir Bilen Can. 2018-10-31. Sects. https://arxiv.org/abs/1810.13159

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