Module

RigidifiedLineBundle_exists_isClosedImmersion_forall_nonempty_pullbackAlong_iso_unit_iff_of_isNoetherianRing.lean

Nyll.JacobianVarieties.Picard.RigidifiedLineBundle_exists_isClosedImmersion_forall_nonempty_pullbackAlong_iso_unit_iff_of_isNoetherianRing
1 declaration indexed from sourceView source ↗

Noetherian closed charts for trivial rigidified line bundles

The affine charts glue to the closed locus where every pullback of the rigidified bundle is isomorphic to the unit bundle.

Declarations

AlgebraicGeometry.RelPicard.RigidifiedLineBundle.exists_isClosedImmersion_forall_nonempty_pullbackAlong_iso_unit_iff_of_isNoetherianRing

Over a Noetherian base, trivial pullbacks of a rigidified bundle are represented by a closed subscheme.

Source context 10 commands

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

section ProofImplementation
open _root_.CategoryTheory
open _root_.CategoryTheory.Limits
open _root_.CategoryTheory.MonoidalCategory
open _root_.AlgebraicGeometry
open _root_.AlgebraicGeometry.RelPicard
open _root_.NeronModelInfra
open _root_.GoodReductionJacobian
open _root_.AlgebraicGeometry.Polarisation
namespace AlgebraicGeometry.RelPicard.RigidifiedLineBundle
theorem exists_isClosedImmersion_forall_nonempty_pullbackAlong_iso_unit_iff_of_isNoetherianRing
    {R : Type} [CommRing R] [IsNoetherianRing R] {A : Scheme.{0}} {f : A ⟶ Spec (CommRingCat.of R)}
    (L : RelativeGroupLaw R f) (hA : AbelianSchemePropertyBundle R f)
    {X : Scheme.{0}} (g : X ⟶ Spec (CommRingCat.of R)) [LocallyOfFiniteType g]
    (M : RigidifiedLineBundle f (L.one (𝟙 (Spec (CommRingCat.of R)))) g) :
    ∃ (Z : Scheme.{0}) (ι : Z ⟶ X), IsClosedImmersion ι ∧
      ∀ {T : Scheme.{0}} (t : T ⟶ Spec (CommRingCat.of R)) (ψ : SchemeHomOver t g),
        Nonempty ((M.pullbackAlong ψ).L ≅
            (RigidifiedLineBundle.unit (c := f) (ε := L.one (𝟙 (Spec (CommRingCat.of R)))) t).L) ↔
          ∃ ψ₀ : T ⟶ Z, ψ₀ ≫ ι = ψ.1