Stability index for algebras with involution

Abstract

In earlier work we developed the theory of signatures of hermitian forms over algebras with involution with respect to orderings on the base field of the algebra and obtained in particular that the total signature of a hermitian form is a continuous function from the space of orderings of that field to $\mathbb{Z}$. In this note we give another presentation of signatures and also introduce and study the stability index of algebras with involution.