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arXiv · 1909.11437

Counterexamples to Hochschild--Kostant--Rosenberg in characteristic $p$

Benjamin Antieau·Bhargav Bhatt·Akhil Mathew
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Abstract

We give counterexamples to the degeneration of the HKR spectral sequence in characteristic $p$, both in the untwisted and twisted settings. We also prove that the de Rham--$\mathrm{HP}$ and crystalline--$\mathrm{TP}$ spectral sequences need not degenerate.

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Benjamin Antieau, Bhargav Bhatt, Akhil Mathew. 2019-09-25. Counterexamples to Hochschild--Kostant--Rosenberg in characteristic $p$. https://arxiv.org/abs/1909.11437

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