Grassmann embeddings of polar Grassmannians

Abstract In this paper we compute the dimension of the Grassmann embeddings of the polar Grassmannians associated to a possibly degenerate Hermitian, alternating or quadratic form with possibly non-maximal Witt index. Moreover, in the characteristic 2 case, when the form is quadratic and non-degenerate with bilinearization of minimal Witt index, we define a generalization of the so-called Weyl embedding (see [4] ) and prove that the Grassmann embedding is a quotient of this generalized ‘Weyl-like’ embedding. We also estimate the dimension of the latter.

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