Motivic classes of classifying stacks of finite groups and unramified cohomology

Federico Scavia

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arXiv · 2003.06995

Motivic classes of classifying stacks of finite groups and unramified cohomology

Federico Scavia

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Abstract

Combining work of Peyre, Colliot-Th\'el\`ene and Voisin, we give the first example of a finite group $G$ such that the motivic class of its classifying stack $BG$ in Ekedahl's Grothendieck ring of stacks over $\mathbb{C}$ is non-trivial and $BG$ has trivial unramified Brauer group.

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Federico Scavia. 2020-03-16. Motivic classes of classifying stacks of finite groups and unramified cohomology. https://arxiv.org/abs/2003.06995

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