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Purity for Similarity Factors

Ivan Panin
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Abstract

Two Azumaya algebras with involutions are considered over a regular local ring. It is proved that if they are isomorphic over the quotient field, then they are isomorphic too. In particular, if two quadratic spaces over such a ring are similar over its quotient field, then these two spaces are similar already over the ring. The result is a consequence of a purity theorem for similarity factors proved in this text and the known fact that rationally isomorphic hermitian spases are locally isomorphic.

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Ivan Panin. 2003-09-03. Purity for Similarity Factors. https://arxiv.org/abs/math/0309054

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