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Closed immersion

In algebraic geometry, a closed immersion of schemes is a morphism of schemes f : Z → X {\displaystyle f:Z\to X} that identifies Z as a closed subset of X such that locally, regular functions on Z can be extended to X. The latter condition can be formalized by saying that f # : O X → f ∗ O Z {\displaystyle f^{\#}:{\mathcal {O}}_{X}\rightarrow f_{\ast…

Characters, Other characterizations & Properties