Processing math: 100%

The Stacks project

Lemma 79.12.9. Let S be a scheme. Let

\xymatrix{ X' \ar[d] \ar[r] & X \ar[d] \\ Y' \ar[r] & Y }

be a fibre product square of algebraic spaces over S. Then

\xymatrix{ (X'/Y')_{fin} \ar[d] \ar[r] & (X/Y)_{fin} \ar[d] \\ Y' \ar[r] & Y }

is a fibre product square of sheaves on (\mathit{Sch}/S)_{fppf}.

Proof. It follows immediately from the definitions that the sheaf (X'/Y')_{fin} is equal to the sheaf Y' \times _ Y (X/Y)_{fin}. \square


Comments (0)

There are also:

  • 2 comment(s) on Section 79.12: The finite part of a morphism

Your email address will not be published. Required fields are marked.

In your comment you can use Markdown and LaTeX style mathematics (enclose it like $\pi$). A preview option is available if you wish to see how it works out (just click on the eye in the toolbar).

Unfortunately JavaScript is disabled in your browser, so the comment preview function will not work.

All contributions are licensed under the GNU Free Documentation License.