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arXiv · 2002.04422

Quasi-split symmetric pairs of $U(\mathfrak{sl}_n)$ and Steinberg varieties of classical type

Yiqiang Li
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Abstract

We provide a Lagrangian construction for the fixed-point subalgebra, together with its idempotent form, in a quasi-split symmetric pair of type $A_{n-1}$. This is obtained inside the limit of a projective system of Borel-Moore homologies of the Steinberg varieties of $n$-step isotropic flag varieties. Arising from the construction are a basis of homological origin for the idempotent form and a geometric realization of rational modules.

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BibTeXRIS

Yiqiang Li. 2020-02-11. Quasi-split symmetric pairs of $U(\mathfrak{sl}_n)$ and Steinberg varieties of classical type. https://arxiv.org/abs/2002.04422

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