Shellability in reductive monoids
نویسندگان
چکیده
منابع مشابه
Shellability in Reductive Monoids
The purpose of this paper is to extend to monoids the work of Björner, Wachs and Proctor on the shellability of the Bruhat-Chevalley order on Weyl groups. Let M be a reductive monoid with unit group G, Borel subgroup B and Weyl group W . We study the partially ordered set of B×Borbits (with respect to Zariski closure inclusion) within a G × G-orbit of M . This is the same as studying a W ×W -or...
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Let M be a reductive monoid with unit group G. Let denote the idempotent cross-section of the G × G-orbits on M . If W is the Weyl group of G and e, f ∈ with e ≤ f , we introduce a projection map from WeW to WfW. We use these projection maps to obtain a new description of the Bruhat-Chevalley order on the Renner monoid of M . For the canonical compactification X of a semisimple group G0 with Bo...
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ژورنال
عنوان ژورنال: Transactions of the American Mathematical Society
سال: 2001
ISSN: 0002-9947,1088-6850
DOI: 10.1090/s0002-9947-01-02806-9