Regularity theorem for totally nonnegative flag varieties
نویسندگان
چکیده
We show that the totally nonnegative part of a partial flag variety $G/P$ (in sense Lusztig) is regular CW complex, confirming conjecture Williams. In particular, closure each positroid cell inside Grassmannian homeomorphic to ball, Postnikov.
منابع مشابه
Shelling Totally Nonnegative Flag Varieties
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Article history: Received 11 January 2008 Available online 24 September 2008
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ژورنال
عنوان ژورنال: Journal of the American Mathematical Society
سال: 2021
ISSN: ['0894-0347', '1088-6834']
DOI: https://doi.org/10.1090/jams/983