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arXiv · 0807.2140

Tits indices over semilocal rings

V. Petrov·A. Stavrova
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Abstract

We give a simplified proof of Tits' classification of semisimple algebraic groups that remains valid over semilocal rings. In particular, we provide explicit necessary and sufficient conditions that anisotropic groups of a given type appear as anisotropic kernels of semisimple groups of a given Tits index. We also give a new proof of the existence of all indices of exceptional inner type using the notion of canonical dimension of projective homogeneous varieties.

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V. Petrov, A. Stavrova. 2010-01-15. Tits indices over semilocal rings. https://arxiv.org/abs/0807.2140

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