--- date: 2022-04-18 12:19 modification date: Monday 18th April 2022 12:19:19 title: "projective" aliases: [quasiprojective scheme, projective scheme, quasiprojective, projective variety] --- Last modified date: <%+ tp.file.last_modified_date() %> --- - Tags: - #todo/untagged - Refs: - #todo/add-references - Links: - #todo/create-links --- # projective scheme - A morphism $f$ is **projective** if it factors as a closed immersion into $\mathbb{P}_{Y}^{n}$, followed by the projection map $\mathbb{P}_{Y}^{n} \rightarrow Y$ for some $n$. - $f$ is **quasiprojective** if it factors as an [open immersion](open%20immersion) followed by a projective morphism. # Results - Every projective variety is [complete](Unsorted/complete.md). - For a [smooth](Unsorted/smooth%20scheme.md) projective variety, the [canonical sheaf](Unsorted/canonical%20bundle.md) can be identified with the [dualizing sheaf](Unsorted/dualizing%20sheaf.md).