Séminaire d'algèbre et de géométrie du 28-11-2022

Exposé de Fatma Kader Bingöl

Le 28-11-2022 à 15:10, en P108 et en ligne.

On the orthogonal u-invariant of a quaternion algebra

Résumé

We provide upper bounds on the u-invariant for skew-hermitian forms over a quaternion algebra with its canonical involution when I^3=0 in terms of the u-invariant of the base field. The bound is optimal in the case where the u-invariant of the base field is 4. This is joint work with K. J. Becher.