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arXiv · 1403.3604

Involutions of varieties and Rost's degree formula

Olivier Haution
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Abstract

To an algebraic variety equipped with an involution, we associate a cycle class in the modulo two Chow group of its fixed locus. This association is functorial with respect to proper morphisms having a degree and preserving the involutions. Specialising to the exchange involution of the square of a complete variety, we obtain Rost's degree formula in arbitrary characteristic (this formula was proved by Rost/Merkurjev in characteristic not two).

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Olivier Haution. 2014-03-14. Involutions of varieties and Rost's degree formula. https://doi.org/10.1515/crelle-2016-0003

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