Module

ProjSpace_exists_isClosedImmersion_isPullback_comp_eq_map.lean

Nyll.AlgebraicCurves.Geometry.Projective.ProjSpace_exists_isClosedImmersion_isPullback_comp_eq_map
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Proj Space exists is Closed Immersion is Pullback comp eq map

Declarations

AlgebraicGeometry.ProjSpace.exists_isClosedImmersion_isPullback_comp_eq_map
Source context 6 commands

Surrounding namespaces, section variables, and local commands at this declaration.

section ProofImplementation
namespace AlgebraicCurves.Geometry.Projective.Proofs
namespace ProjSpace_exists_isClosedImmersion_isPullback_comp_eq_map
universe u
open CategoryTheory CategoryTheory.Limits AlgebraicGeometry MvPolynomial TensorProduct
attribute [local instance] MvPolynomial.gradedAlgebra
theorem _root_.AlgebraicGeometry.ProjSpace.exists_isClosedImmersion_isPullback_comp_eq_map
    {A : Type u} [CommRing A] {n : ℕ} {Z : Scheme.{u}}
    (ι : Z ⟶ Proj (MvPolynomial.homogeneousSubmodule (Fin (n + 1)) A)) [IsClosedImmersion ι]
    (B : Type u) [CommRing B] [Algebra A B] :
    ∃ (Z' : Scheme.{u}) (ι' : Z' ⟶ Proj (MvPolynomial.homogeneousSubmodule (Fin (n + 1)) B))
      (_ : IsClosedImmersion ι') (e : Z' ⟶ Z),
      IsPullback e (ι' ≫ ProjSpace.π B n) (ι ≫ ProjSpace.π A n) (Spec.map (CommRingCat.ofHom
        (algebraMap A B))) ∧
      e ≫ ι = ι' ≫ ProjSpace.map A B n