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arXiv · 2607.06454

Categories with conjugation and octagons of Witt groups

David W. Lewis·Jean-Pierre Tignol
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Abstract

A categorical approach is proposed for the construction of 8-periodic chain complexes of Witt groups of categories with duality. Exactness of the resulting sequences is proved under the hypothesis that the categories are abelian and artinian or when the endomorphism algebra of each object is semilocal and rad-adically complete.

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David W. Lewis, Jean-Pierre Tignol. 2026-07-07. Categories with conjugation and octagons of Witt groups. https://doi.org/10.1016/j.jalgebra.2026.06.024

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