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arXiv · 1204.0379

Unitary grassmannians

Nikita A. Karpenko
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Abstract

We study projective homogeneous varieties under an action of a projective unitary group (of outer type). We are especially interested in the case of (unitary) grassmannians of totally isotropic subspaces of a hermitian form over a field, the main result saying that these grassmannians are 2-incompressible if the hermitian form is generic. Applications to orthogonal grassmannians are provided.

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Nikita A. Karpenko. 2012-04-02. Unitary grassmannians. https://arxiv.org/abs/1204.0379

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