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arXiv · 2604.03062

On de Rham--Witt Cohomology of Classifying Stacks

Shizhang Li·Yuan Yang
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Abstract

We give an example of proper smooth fourfold over a perfect field k of characteristic p > 0 with asymmetric Hodge--Witt numbers in total degree 3. Our example is sharp both in terms of dimension and total degree. We arrive at our example by computing and approximating the Hodge--Witt cohomology groups of the classifying stack B alpha_p.

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Shizhang Li, Yuan Yang. 2026-04-03. On de Rham--Witt Cohomology of Classifying Stacks. https://arxiv.org/abs/2604.03062

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