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arXiv · 2006.04230

First order thickenings and cotorsors

Nicholas Mertes
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Abstract

Let $X$ be a scheme and let $\mathcal{M}$ be a quasi-coherent sheaf on $X$. Then $\mathcal{M}$ can be viewed as a cogroup object in the category of schemes under $X$. We show that the category of first order thickenings of $X$ by $\mathcal{M}$ is equivalent to the category of $\mathcal{M}$-cotorsors.

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Nicholas Mertes. 2020-06-07. First order thickenings and cotorsors. https://arxiv.org/abs/2006.04230

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