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arXiv · 1711.05252

Lifting zero-dimensional schemes and divided powers

Adrian Langer
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Abstract

We study divided power structures on finitely generated $k$-algebras, where $k$ is a field of positive characteristic $p$. As an application we show examples of $0$-dimensional Gorenstein $k$-schemes that do not lift to a fixed noetherian local ring of non-equal characteristic. We also show that Frobenius neighbourhoods of a singular point of a general hypersurface of large dimension have no liftings to mildly ramified rings of non-equal characteristic.

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Adrian Langer. 2017-11-14. Lifting zero-dimensional schemes and divided powers. https://doi.org/10.1112/blms.12151

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