论文标题
Bruhat间隔多型的单骨骼posets
One-skeleton posets of Bruhat interval polytopes
论文作者
论文摘要
由科达玛（Kodama）和威廉姆斯（Williams）引入的，Bruhat间隔的多型与舒伯特品种中的圆环轨道闭合和完全阳性的研究密切相关。我们表明，这些多面体的1个骨骼poset是晶格，并在多型简单时进行分类，从而解决了弗雷泽，李 - 马苏达和李 - 马苏达 - 公园的开放问题和猜想。特别是，我们对舒伯特品种中的通用圆环关闭时进行分类。
Introduced by Kodama and Williams, Bruhat interval polytopes are generalized permutohedra closely connected to the study of torus orbit closures and total positivity in Schubert varieties. We show that the 1-skeleton posets of these polytopes are lattices and classify when the polytopes are simple, thereby resolving open problems and conjectures of Fraser, of Lee--Masuda, and of Lee--Masuda--Park. In particular, we classify when generic torus orbit closures in Schubert varieties are smooth.
