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arXiv · 2209.09392

Ind-étale vs Formally étale

Shubhodip Mondal·Alapan Mukhopadhyay
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Abstract

We show that when $A$ is a reduced algebra over a characteristic zero field $k$ and the module of Kähler differentials $Ω_{A/k}=0$, then $A$ is ind-étale, partially answering a question of Bhatt. As further applications of this result, we deduce a rigidity property of Hochschild homology and special instances of Weibel's conjecture and Vorst's conjecture without any noetherian assumptions.

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Shubhodip Mondal, Alapan Mukhopadhyay. 2022-09-20. Ind-étale vs Formally étale. https://arxiv.org/abs/2209.09392

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