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arXiv · 2403.15561

Invariants de Witt des involutions de bas degr\'e en caract\'eristique 2

Jean-Pierre Tignol
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Abstract

A $3$-fold and a $5$-fold quadratic Pfister forms are canonically associated to every symplectic involution on a central simple algebra of degree $8$ over a field of characteristic $2$. The same construction on central simple algebras of degree $4$ associates to every unitary involution a $2$-fold and a $4$-fold Pfister quadratic forms, and to every orthogonal involution a $1$-fold and a $3$-fold quasi-Pfister forms. These forms hold structural information on the algebra with involution.

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BibTeXRIS

Jean-Pierre Tignol. 2024-03-22. Invariants de Witt des involutions de bas degr\'e en caract\'eristique 2. https://arxiv.org/abs/2403.15561

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