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arXiv · 1902.05296

Un adjoint

Daniel Ferrand
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Abstract

Given a scheme S and a flat morphism T \to S of finite presentation we define a surjective S-morphism to an {\'e}tale and separated S-scheme, which is universal in an obvious sense. Properties of this morphism are deduced from a thorough uses of quotients by equivalence relations whose graph is open and closed.

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Daniel Ferrand. 2019-02-14. Un adjoint. https://arxiv.org/abs/1902.05296

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