Module

DescentAction_effective_of_finiteEtale.lean

Nyll.AlgebraicCurves.Geometry.Descent.DescentAction_effective_of_finiteEtale
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Descent Action effective of finite Etale

Declarations

AlgebraicGeometry.DescentAction.effective_of_finiteEtale
Source context 4 commands

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

section ProofImplementation
namespace AlgebraicCurves.Geometry.Descent.Proofs.DescentAction_effective_of_finiteEtale
universe u
open CategoryTheory CategoryTheory.Limits AlgebraicGeometry Opposite
theorem _root_.AlgebraicGeometry.DescentAction.effective_of_finiteEtale
    (R : Type u) [CommRing R] (R' : Type u) [CommRing R'] [Algebra R R'] [Module.Finite R R']
    [Algebra.Etale R R'] [Module.FaithfullyFlat R R']
    {X' : Scheme.{u}} {x' : X' ⟶ Spec (CommRingCat.of R')}
    (A : DescentAction (Spec.map (CommRingCat.ofHom (algebraMap R R'))) x')
    (haff : ∀ S : Finset X', ∃ U : X'.Opens, IsAffineOpen U ∧ ∀ x ∈ S, x ∈ U) :
    A.Effective