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arXiv · 1103.5777

Isotropy of unitary involutions

Nikita Karpenko·Maksim Zhykhovich
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Abstract

We prove the so-called Unitary Isotropy Theorem, a result on isotropy of a unitary involution. The analogous previously known results on isotropy of orthogonal and symplectic involutions as well as on hyperbolicity of orthogonal, symplectic, and unitary involutions are formal consequences of this theorem. A component of the proof is a detailed study of the quasi-split unitary grassmannians.

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Nikita Karpenko, Maksim Zhykhovich. 2012-06-19. Isotropy of unitary involutions. https://doi.org/10.1007/s11425-012-4364-4

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