Geometric hyperplanes of the half-spin geometries arise from embeddings
نویسنده
چکیده
Let the point-line geometry Γ = (P ,L) be a half-spin geometry of type Dn,n. Then, for every embedding of Γ in the projective space P(V ), where V is a vector space of dimension 2n−1, it is true that every hyperplane of Γ arises from that embedding. It follows that any embedding of this dimension is universal. There are no embeddings of higher dimension. A corollary of this result and the fact that Veldkamp lines exist ([6]), is that the Veldkamp space of any half-spin geometry (n ≥ 4) is a projective space.
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تاریخ انتشار 2000