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arXiv · 2312.03934

Period-index in top cohomology over semiglobal fields

Sarah Dijols·Raman Parimala·Ramdorai Sujatha·Charlotte Ure
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Abstract

We prove a common slot lemma for symbols in top cohomology classes over semiglobal fields. Furthermore, we prove that period and index agree for general top cohomology classes over such fields. We discuss applications to quadratic forms and related open problems.

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Sarah Dijols, Raman Parimala, Ramdorai Sujatha, Charlotte Ure. 2023-12-06. Period-index in top cohomology over semiglobal fields. https://arxiv.org/abs/2312.03934

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