Module

Scheme_Hom_map_germ_ker_ideal_eq_ker_stalkMap.lean

Nyll.AlgebraicCurves.Geometry.Schemes.Scheme_Hom_map_germ_ker_ideal_eq_ker_stalkMap
2 declarations indexed from sourceView source ↗

Scheme Hom map germ ker ideal eq ker stalk Map

Imports5
  • Mathlib.AlgebraicGeometry.Morphisms.ClosedImmersion
  • Mathlib.AlgebraicGeometry.AffineScheme
  • Mathlib.AlgebraicGeometry.IdealSheaf.Basic
  • Mathlib.RingTheory.Localization.Basic
  • Mathlib.Tactic.Set
Imported by2

Declarations

AlgebraicCurves.Geometry.Schemes.Proofs.Scheme_Hom_map_germ_ker_ideal_eq_ker_stalkMap.PtGerm.map_germ_ker_ideal_eq_ker_stalkMap
Source context 5 commands

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

section ProofImplementation
namespace AlgebraicCurves.Geometry.Schemes.Proofs.Scheme_Hom_map_germ_ker_ideal_eq_ker_stalkMap
universe u
open CategoryTheory CategoryTheory.Limits AlgebraicGeometry TopologicalSpace
namespace PtGerm
theorem map_germ_ker_ideal_eq_ker_stalkMap {X Y : Scheme.{u}} (σ : Y ⟶ X) [IsClosedImmersion σ] (y
  : Y)
    (U : X.affineOpens) (hx : σ.base y ∈ (U : X.Opens)) :
    Ideal.map (X.presheaf.germ (U : X.Opens) (σ.base y) hx).hom (σ.ker.ideal U) = RingHom.ker
      (σ.stalkMap y).hom
AlgebraicGeometry.Scheme.Hom.map_germ_ker_ideal_eq_ker_stalkMap
Source context 4 commands

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

section ProofImplementation
namespace AlgebraicCurves.Geometry.Schemes.Proofs.Scheme_Hom_map_germ_ker_ideal_eq_ker_stalkMap
universe u
open CategoryTheory CategoryTheory.Limits AlgebraicGeometry TopologicalSpace
theorem _root_.AlgebraicGeometry.Scheme.Hom.map_germ_ker_ideal_eq_ker_stalkMap {X Y : Scheme.{u}}
  (σ : Y ⟶ X) [IsClosedImmersion σ]
    (y : Y) (U : X.affineOpens) (hx : σ.base y ∈ (U : X.Opens)) :
    Ideal.map (X.presheaf.germ (U : X.Opens) (σ.base y) hx).hom (σ.ker.ideal U) = RingHom.ker
      (σ.stalkMap y).hom