Module

RigidifiedLineBundle_subsingleton_iso_map_pullback_rigSection_comp_eq.lean

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

Show that the type of line bundle isomorphisms respecting fixed rigidifications is a subsingleton.

Declarations

AlgebraicGeometry.RelPicard.RigidifiedLineBundle.subsingleton_iso_map_pullback_rigSection_comp_eq
Source context 6 commands

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

section ProofImplementation
namespace JacobianVarieties.Picard.Proofs
namespace RigidifiedLineBundle_subsingleton_iso_map_pullback_rigSection_comp_eq
universe u
open CategoryTheory CategoryTheory.Limits AlgebraicGeometry AlgebraicGeometry.RelPicard
    NeronModelInfra
with_weak_namespace _root_.AlgebraicGeometry.RelPicard.RigidifiedLineBundle
theorem subsingleton_iso_map_pullback_rigSection_comp_eq
    (R : Type u) [CommRing R] {C : Scheme.{u}} (c : C ⟶ Spec (CommRingCat.of R))
    (ε : SchemeHomOver (𝟙 (Spec (CommRingCat.of R))) c)
    (hH0 : ∀ (A : Type u) [CommRing A] [Algebra R A],
      let _ : Algebra A Γ(Limits.pullback c (Scheme.TwoAffineOpenCover.specMap R A), ⊤) :=
        Scheme.TwoAffineOpenCover.algebraOfHom
          (Limits.pullback.snd c (Scheme.TwoAffineOpenCover.specMap R A)) ⊤
      Function.Bijective (algebraMap A Γ(Limits.pullback c (Scheme.TwoAffineOpenCover.specMap R
        A), ⊤)))
    {T : Scheme.{u}} (t : T ⟶ Spec (CommRingCat.of R)) (M M' : RigidifiedLineBundle c ε t)
    (α : (Scheme.Modules.pullback (rigSection c t ε)).obj M.L ≅ SheafOfModules.unit T.ringCatSheaf)
    (α' : (Scheme.Modules.pullback (rigSection c t ε)).obj M'.L ≅ SheafOfModules.unit
      T.ringCatSheaf) :
    Subsingleton {φ : M.L ≅ M'.L // (Scheme.Modules.pullback (rigSection c t ε)).mapIso φ ≪≫ α'
      = α} :=
  ⟨fun a b => Subtype.ext
    (AlgebraicGeometry.RelPicard.RigidifiedLineBundle.iso_eq_of_map_pullback_rigSection_comp_eq
      R c ε hH0 t M M' α α' a.1 b.1 a.2 b.2)⟩