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arXiv · 0903.4243

Incompressibility of orthogonal Grassmannians of rank 2

Bryant G. Mathews
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Abstract

For a nondegenerate quadratic form phi on a vector space V of dimension 2n + 1, let X_d be the variety of d-dimensional totally isotropic subspaces of V. We give a sufficient condition for X_2 to be 2-incompressible, generalizing in a natural way the known sufficient conditions for X_1 and X_n. Key ingredients in the proof include the Chernousov-Merkurjev method of motivic decomposition as well as Pragacz and Ratajski's characterization of the Chow ring of (X_2)_E, where E is a field extension splitting phi.

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Bryant G. Mathews. 2009-03-25. Incompressibility of orthogonal Grassmannians of rank 2. https://arxiv.org/abs/0903.4243

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