Base subsets of polar Grassmannians
نویسنده
چکیده
Let ∆ be a thick building of type Xn = Cn,Dn. Let also Gk be the Grassmannian of k-dimensional singular subspaces of the associated polar space Π (of rank n). We write Gk for the corresponding shadow space of type Xn,k. Every bijective transformation of Gk preserving the class of base subsets (the shadows of apartments) is a collineation of Gk, and it is induced by a collineation of Π if n 6= 4 or k 6= 1.
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ورودعنوان ژورنال:
- J. Comb. Theory, Ser. A
دوره 114 شماره
صفحات -
تاریخ انتشار 2007