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arXiv · 2505.22178

Signature maps from positive cones on algebras with involution

Vincent Astier·Thomas Unger
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Abstract

We introduced positive cones in an earlier paper as a notion of ordering on central simple algebras with involution that corresponds to signatures of hermitian forms. In the current paper we describe signatures of hermitian forms directly out of positive cones, and also use this approach to rectify a problem that affected some results in the previously mentioned paper.

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Vincent Astier, Thomas Unger. 2025-05-28. Signature maps from positive cones on algebras with involution. https://arxiv.org/abs/2505.22178

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