On the Topology of the Combinatorial Flag Varieties —From a New Point of View
نویسندگان
چکیده
We prove that the simplicial complex Ωn of chains of matroids (with respect to the ordering by the quotient relation) on n elements is shellable. This follows from a more general result on shellability of the simplicial complex of W -matroids for an arbitrary finite Coxeter group W . The paper generalises the well known results by Solomon-Tits and Björner on spherical buildings, and improves the results of [6]. ∗Partially supported by PSC-CUNY Research Award 6–69437 and EPSRC Research Grant GR/M24707.
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تاریخ انتشار 2000