The Stacks project

Lemma 86.19.3. Let $S$ be a scheme. Let $f : X \to Y$ and $g : Y \to Z$ be morphisms of formal algebraic spaces over $S$. If $g \circ f : X \to Z$ is representable by algebraic spaces, then $f : X \to Y$ is representable by algebraic spaces.

Proof. Note that the diagonal of $Y \to Z$ is representable by Lemma 86.15.5. Thus $X \to Y$ is representable by algebraic spaces by Bootstrap, Lemma 79.3.10. $\square$

Comments (2)

Comment #1948 by Brian Conrad on

In the proof, replace :" with "".

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