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arXiv · 2604.08069

Differential graded Brauer groups over dg-rings

Xiaoxiao Xu·Alexander Zimmermann
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Abstract

Brauer groups of graded rings were defined and studied by Caenepeel and van Oystaeyen. We study the question what happens to this group if a ${\mathbb Z}$-graded ring carries a differential graded structure in addition. We define a Brauer group for differential graded algebras over differential graded graded-commutative or commutative base rings. Based on previous work we give an explicit classification of dg-fields, and compute as an example the so-defined Brauer group in each case explicitly.

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Xiaoxiao Xu, Alexander Zimmermann. 2026-04-09. Differential graded Brauer groups over dg-rings. https://arxiv.org/abs/2604.08069

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