Module

Scheme_OrderedAffineCover_exists_refinement_preimage_preimage_of_isSeparated.lean

Nyll.AlgebraicCurves.Geometry.Schemes.Scheme_OrderedAffineCover_exists_refinement_preimage_preimage_of_isSeparated
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Scheme Ordered Affine Cover exists refinement preimage preimage of is Separated

Declarations

AlgebraicGeometry.Scheme.OrderedAffineCover.exists_refinement_preimage_preimage_of_isSeparated
Source context 5 commands

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

section ProofImplementation
namespace AlgebraicGeometry.Scheme.OrderedAffineCover
open _root_.AlgebraicCurves.Geometry.Schemes.Proofs in
open Scheme_OrderedAffineCover_exists_refinement_preimage_preimage_of_isSeparated in
open CategoryTheory CategoryTheory.Limits AlgebraicGeometry in
theorem exists_refinement_preimage_preimage_of_isSeparated
    {R : Type} [CommRing R] {X : Scheme.{0}} (f : X ⟶ Spec (CommRingCat.of R)) [IsSeparated f]
    (𝒦 : X.OrderedAffineCover) (h₁ h₂ : X ⟶ X) [IsAffineHom h₁] [IsAffineHom h₂] :
    ∃ (𝒲 : X.OrderedAffineCover) (lam₁ lam₂ : 𝒲.ι → 𝒦.ι),
      (∀ w, 𝒲.U w ≤ h₁ ⁻¹ᵁ 𝒦.U (lam₁ w)) ∧ (∀ w, 𝒲.U w ≤ h₂ ⁻¹ᵁ 𝒦.U (lam₂ w))