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arXiv · 2304.03598

An Artin-Schreier-type theory for signatures of hermitian forms over involutions

Nicolas Garrel
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Abstract

In the case of quadratic forms over a field, it is well-known that the prime spectrum of the Witt ring and the space of orderings of the field determine one another, through associated signature maps. We show that a sililar relation holds for hermitian forms over algebras with involution of the first kind, replacing the usual Witt ring with the mixed Witt ring of such an algebra.

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Nicolas Garrel. 2023-04-07. An Artin-Schreier-type theory for signatures of hermitian forms over involutions. https://arxiv.org/abs/2304.03598

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