Adjoint algebraic groups as automorphism groups of a projector on a central simple algebra

Viktor Petrov; Andrei Semenov

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arXiv · 2004.08191

Adjoint algebraic groups as automorphism groups of a projector on a central simple algebra

Viktor Petrov·Andrei Semenov

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Abstract

We show that any adjoint absolutely simple linear algebraic group over a field of characteristic zero is the automorphism group of some projector on a central simple algebra. Projective homogeneous varieties can be described in these terms; in particular, we reproduce quadratic equations by Lichtenstein defining them.

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Viktor Petrov, Andrei Semenov. 2020-04-17. Adjoint algebraic groups as automorphism groups of a projector on a central simple algebra. https://arxiv.org/abs/2004.08191

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