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arXiv · 2102.03608

Coordinate rings and birational charts

Sergey Fomin·George Lusztig
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Abstract

Let $G$ be a semisimple simply connected complex algebraic group. Let $U$ be the unipotent radical of a Borel subgroup in $G$. We describe the coordinate rings of $U$ (resp., $G/U$, $G$) in terms of two (resp., four, eight) birational charts introduced in [L94, L19] in connection with the study of total positivity.

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BibTeXRIS

Sergey Fomin, George Lusztig. 2021-02-06. Coordinate rings and birational charts. https://arxiv.org/abs/2102.03608

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