The Stacks project

Lemma 38.34.4. Let $X$ be a locally Noetherian scheme. A family of morphisms $\{ f_ i : X_ i \to X\} _{i \in I}$ with target $X$ is an h covering if and only if it is a ph covering.

Proof. By Definition 38.34.2 a h covering is a ph covering. Conversely, if $\{ f_ i : X_ i \to X\} $ is a ph covering, then the morphisms $f_ i$ are locally of finite type (Topologies, Definition 34.8.4). Since $X$ is locally Noetherian, each $f_ i$ is locally of finite presentation and we see that we have a h covering by definition. $\square$

Comments (0)

Post a comment

Your email address will not be published.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.




In order to prevent bots from posting comments, we would like you to prove that you are human. You can do this by filling in the name of the current tag in the following input field. As a reminder, this is tag 0H45. Beware of the difference between the letter 'O' and the digit '0'.



View Lemma 38.34.4 as pdf