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arXiv · 1211.3443

Twisted gamma filtration and algebras with orthogonal involution

Caroline Junkins
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Abstract

For the Grothendieck group of a split simple linear algebraic group, the twisted gamma-filtration provides a useful tool for constructing torsion elements in gamma-rings of twisted flag varieties. In this paper, we construct a non-trivial torsion element in the gamma-ring of a complete flag variety twisted by means of a PGO-torsor. This generalizes the construction in the HSpin case previously obtained by Zainoulline. We use this torsion element to study algebras with orthogonal involutions.

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Caroline Junkins. 2012-11-14. Twisted gamma filtration and algebras with orthogonal involution. https://arxiv.org/abs/1211.3443

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