Schubert Patches Degenerate to Subword Complexes
نویسندگان
چکیده
منابع مشابه
Schubert Patches Degenerate to Subword Complexes
We study the intersections of general Schubert varieties Xw with permuted big cells, and give an inductive degeneration of each such “Schubert patch” to a StanleyReisner scheme. Similar results had been known for Schubert patches in various types of Grassmannians. Wemaintain reducedness using the results of [Knutson 2007] on automatically reduced degenerations, or throughmore standard cohomolog...
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We consider stratifications of schemes by subvarieties, and introduce the notion of a stratification generated by a collection of (reduced) subschemes. We recall some basics of Gröbner degenerations (just for lex order) and Stanley-Reisner theory. We then state the main theorem, that the lex init of a Kazhdan-Lusztig variety in BottSamelson coördinates is the Stanley-Reisner scheme of a subword...
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ژورنال
عنوان ژورنال: Transformation Groups
سال: 2008
ISSN: 1083-4362,1531-586X
DOI: 10.1007/s00031-008-9013-1