The Stacks project

Definition 29.43.1. Let $f : X \to S$ be a morphism of schemes.

  1. We say $f$ is projective if $X$ is isomorphic as an $S$-scheme to a closed subscheme of a projective bundle $\mathbf{P}(\mathcal{E})$ for some quasi-coherent, finite type $\mathcal{O}_ S$-module $\mathcal{E}$.

  2. We say $f$ is H-projective if there exists an integer $n$ and a closed immersion $X \to \mathbf{P}^ n_ S$ over $S$.

  3. We say $f$ is locally projective if there exists an open covering $S = \bigcup U_ i$ such that each $f^{-1}(U_ i) \to U_ i$ is projective.

Comments (4)

Comment #204 by Rex on

Typo: "if there exists and integer"

Comment #218 by on

Fixed, see here. Moreover, the other typos you found are fixed in the same commit. Thanks!

Comment #1846 by Peter Johnson on

The typo in (2) noticed by Rex, supposedly corrected in 2013, is not gone.

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