The discriminant Pfister form of an algebra with involution of capacity four
Rings and Algebras
2024-09-17 v3 K-Theory and Homology
Abstract
To an orthogonal or unitary involution on a central simple algebra of degree 4, or to a symplectic involution on a central simple algebra of degree 8, we associate a Pfister form that characterises the decomposability of the algebra with involution. In this way we obtain a unified approach to known decomposability criteria for several cases, and a new result for symplectic involutions on degree algebras in characteristic 2.
Keywords
Cite
@article{arxiv.2008.08953,
title = {The discriminant Pfister form of an algebra with involution of capacity four},
author = {Karim Johannes Becher and Nicolas Grenier-Boley and Jean-Pierre Tignol},
journal= {arXiv preprint arXiv:2008.08953},
year = {2024}
}