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arXiv · 1608.02730

Pfister involutions in characteristic two

A. -H. Nokhodkar
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Abstract

In characteristic two, it is shown that a central simple algebra of degree equal to a power of two with anisotropic orthogonal involution is totally decomposable, if it becomes either anisotropic or metabolic over all extensions of the ground field. A similar result is obtained for the case where this algebra with involution is Brauer-equivalent to a quaternion algebra and it becomes adjoint to a bilinear Pfister form over all splitting fields of the algebra.

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A. -H. Nokhodkar. 2016-08-09. Pfister involutions in characteristic two. https://doi.org/10.1112/blms.12048

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