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arXiv · 1909.04014

Structure of geometrically non-reduced varieties

Lena Ji·Joe Waldron
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Abstract

We prove a structural result for geometrically non-reduced varieties and give applications to Fano varieties. For example, we show that if $X$ is the generic fibre of a Mori fibre space of relative dimension $n$, and the characteristic is $p>2n+1$, then any geometric non-reducedness of $X$ comes from the base of some fibration.

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Lena Ji, Joe Waldron. 2019-09-09. Structure of geometrically non-reduced varieties. https://doi.org/10.1090/tran/8388

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