Module

finite_setOf_pullback_fst_eq_of_isClosed_singleton.lean

Nyll.AlgebraicCurves.Geometry.Schemes.finite_setOf_pullback_fst_eq_of_isClosed_singleton
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finite set Of pullback fst eq of is Closed singleton

Imports6
  • Mathlib.AlgebraicGeometry.Morphisms.Finite
  • Mathlib.AlgebraicGeometry.Morphisms.ClosedImmersion
  • Mathlib.AlgebraicGeometry.Pullbacks
  • Mathlib.RingTheory.Artinian.Module
  • Mathlib.RingTheory.TensorProduct.Finite
  • Mathlib.Tactic.Set
Imported by1

Declarations

AlgebraicGeometry.finite_setOf_pullback_fst_eq_of_isClosed_singleton
Source context 5 commands

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

section ProofImplementation
namespace AlgebraicCurves.Geometry.Schemes.Proofs.finite_setOf_pullback_fst_eq_of_isClosed_singleton
universe u
open CategoryTheory CategoryTheory.Limits AlgebraicGeometry
open scoped TensorProduct
theorem _root_.AlgebraicGeometry.finite_setOf_pullback_fst_eq_of_isClosed_singleton
    {κ Ω : Type u} [Field κ] [Field Ω] [Algebra κ Ω]
    {X : Scheme.{u}} (f : X ⟶ Spec (CommRingCat.of κ)) [LocallyOfFiniteType f]
    (z : X) (hz : IsClosed ({z} : Set X)) :
    {w : ↥(Limits.pullback f (Spec.map (CommRingCat.ofHom (algebraMap κ Ω)))) |
      (Limits.pullback.fst f (Spec.map (CommRingCat.ofHom (algebraMap κ Ω)))) w = z}.Finite