Module

ThetaBundle.lean

Nyll.JacobianVarieties.Picard.ThetaBundle
4 declarations indexed from sourceView source ↗

Relative Picard and theta bundles

The Picard bundle pushes a tensor product of a rigidified line bundle and a module forward to the test scheme. The theta bundle is the dual of the determinant of this pushforward after twisting by the chosen relative section.

Imports4
Imported by106

Declarations

AlgebraicGeometry.RelPicard.picardBundle

Push the tensor product with M forward along the projection to the test scheme.

Source context 5 commands

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

noncomputable section
universe u
open CategoryTheory CategoryTheory.Limits AlgebraicGeometry NeronModelInfra MonoidalCategory
namespace AlgebraicGeometry.RelPicard
variable {R : Type u} [CommRing R] {C : Scheme.{u}} (c : C ⟶ Spec (CommRingCat.of R))
  (ε : SchemeHomOver (𝟙 (Spec (CommRingCat.of R))) c) {T : Scheme.{u}}
  (t : T ⟶ Spec (CommRingCat.of R))
def picardBundle (M : RigidifiedLineBundle c ε t) (N : (pullback c t).Modules) : T.Modules
AlgebraicGeometry.RelPicard.thetaBundle

The dual determinant of the Picard bundle after a relative section twist.

Source context 5 commands

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

noncomputable section
universe u
open CategoryTheory CategoryTheory.Limits AlgebraicGeometry NeronModelInfra MonoidalCategory
namespace AlgebraicGeometry.RelPicard
variable {R : Type u} [CommRing R] {C : Scheme.{u}} (c : C ⟶ Spec (CommRingCat.of R))
  (ε : SchemeHomOver (𝟙 (Spec (CommRingCat.of R))) c) {T : Scheme.{u}}
  (t : T ⟶ Spec (CommRingCat.of R))
def thetaBundle (M : RigidifiedLineBundle c ε t) (r n : ℕ) : T.Modules
AlgebraicGeometry.RelPicard.picardBundle_def
Source context 5 commands

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

noncomputable section
universe u
open CategoryTheory CategoryTheory.Limits AlgebraicGeometry NeronModelInfra MonoidalCategory
namespace AlgebraicGeometry.RelPicard
variable {R : Type u} [CommRing R] {C : Scheme.{u}} (c : C ⟶ Spec (CommRingCat.of R))
  (ε : SchemeHomOver (𝟙 (Spec (CommRingCat.of R))) c) {T : Scheme.{u}}
  (t : T ⟶ Spec (CommRingCat.of R))
theorem picardBundle_def (M : RigidifiedLineBundle c ε t) (N : (pullback c t).Modules) :
    picardBundle c ε t M N = (Scheme.Modules.pushforward (pullback.snd c t)).obj (M.L ⊗ N)
AlgebraicGeometry.RelPicard.thetaBundle_def
Source context 5 commands

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

noncomputable section
universe u
open CategoryTheory CategoryTheory.Limits AlgebraicGeometry NeronModelInfra MonoidalCategory
namespace AlgebraicGeometry.RelPicard
variable {R : Type u} [CommRing R] {C : Scheme.{u}} (c : C ⟶ Spec (CommRingCat.of R))
  (ε : SchemeHomOver (𝟙 (Spec (CommRingCat.of R))) c) {T : Scheme.{u}}
  (t : T ⟶ Spec (CommRingCat.of R))
theorem thetaBundle_def (M : RigidifiedLineBundle c ε t) (r n : ℕ) :
    thetaBundle c ε t M r n =
      Scheme.Modules.dual (Scheme.Modules.det n
        (picardBundle c ε t M (sectionTwist c ε t r)))