Module

FppfSiteCohomology.lean

Nyll.AlgebraicCurves.Cohomology.Sheaves.FppfSiteCohomology
61 declarations indexed from sourceView source ↗

The small fppf site and its abelian sheaf cohomology.

Imports16
  • Mathlib.AlgebraicGeometry.Sites.Fpqc
  • Mathlib.AlgebraicGeometry.Sites.Etale
  • Mathlib.AlgebraicGeometry.Sites.Small
  • Mathlib.AlgebraicGeometry.Morphisms.FinitePresentation
  • Mathlib.AlgebraicGeometry.Morphisms.Flat
  • Mathlib.CategoryTheory.Sites.SheafCohomology.Basic
  • Mathlib.CategoryTheory.Sites.ConstantSheaf
  • Mathlib.CategoryTheory.Sites.Over
  • Mathlib.CategoryTheory.Limits.MorphismProperty
  • Mathlib.CategoryTheory.MorphismProperty.Limits
  • Mathlib.CategoryTheory.Abelian.GrothendieckAxioms.Sheaf
  • Mathlib.CategoryTheory.Abelian.GrothendieckCategory.HasExt
  • Mathlib.CategoryTheory.Adjunction.Additive
  • Mathlib.Algebra.Category.Grp.AB
  • Mathlib.Algebra.Category.Grp.Ulift
  • Mathlib.Algebra.Category.Grp.ForgetCorepresentable
Imported by1

Declarations

Source context 3 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
instance : MorphismProperty.IsMultiplicative @LocallyOfFinitePresentation where
  id_mem _ := inferInstance
AlgebraicGeometry.Scheme.fppfProperty

The morphism property of being flat and locally of finite presentation.

Source context 3 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
abbrev fppfProperty : MorphismProperty Scheme.{u}
AlgebraicGeometry.Scheme.fppfProperty_isStableUnderBaseChange
Source context 3 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
theorem fppfProperty_isStableUnderBaseChange :
    fppfProperty.{u}.IsStableUnderBaseChange
AlgebraicGeometry.Scheme.fppfProperty_isMultiplicative
Source context 3 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
theorem fppfProperty_isMultiplicative : fppfProperty.{u}.IsMultiplicative
AlgebraicGeometry.Scheme.fppfProperty_isStableUnderComposition
Source context 3 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
theorem fppfProperty_isStableUnderComposition :
    fppfProperty.{u}.IsStableUnderComposition
AlgebraicGeometry.Scheme.fppfProperty_respectsIso
Source context 3 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
theorem fppfProperty_respectsIso : fppfProperty.{u}.RespectsIso
AlgebraicGeometry.Scheme.fppfProperty_containsIdentities
Source context 3 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
theorem fppfProperty_containsIdentities : fppfProperty.{u}.ContainsIdentities
AlgebraicGeometry.Scheme.fppfProperty_hasPullbacks
Source context 3 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
theorem fppfProperty_hasPullbacks : fppfProperty.{u}.HasPullbacks
AlgebraicGeometry.Scheme.fppfPrecoverage_eq_precoverage_fppfProperty
Source context 4 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
theorem fppfPrecoverage_eq_precoverage_fppfProperty :
    fppfPrecoverage.{u} = Scheme.precoverage fppfProperty
Source context 4 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
instance : fppfPrecoverage.{u}.HasIsos
Source context 4 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
instance : fppfPrecoverage.{u}.HasPullbacks
AlgebraicGeometry.Scheme.fppfPretopology

The pretopology generated by jointly surjective fppf covering families.

Source context 4 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
def fppfPretopology : Pretopology Scheme.{u}
AlgebraicGeometry.Scheme.fppfTopology_eq_grothendieckTopology
Source context 4 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
theorem fppfTopology_eq_grothendieckTopology :
    fppfTopology.{u} = Scheme.grothendieckTopology fppfProperty
AlgebraicGeometry.Scheme.fppfTopology_eq_toGrothendieck_fppfPretopology
Source context 4 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
theorem fppfTopology_eq_toGrothendieck_fppfPretopology :
    fppfTopology.{u} = fppfPretopology.toGrothendieck
AlgebraicGeometry.Scheme.etale_le_fppfProperty
Source context 4 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
theorem etale_le_fppfProperty : @Etale ≤ fppfProperty.{u}
AlgebraicGeometry.Scheme.etalePrecoverage_le_fppfPrecoverage
Source context 4 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
theorem etalePrecoverage_le_fppfPrecoverage : etalePrecoverage.{u} ≤ fppfPrecoverage
AlgebraicGeometry.Scheme.etaleTopology_le_fppfTopology
Source context 4 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
theorem etaleTopology_le_fppfTopology : etaleTopology.{u} ≤ fppfTopology
AlgebraicGeometry.Scheme.zariskiTopology_le_fppfTopology
Source context 4 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
theorem zariskiTopology_le_fppfTopology : zariskiTopology.{u} ≤ fppfTopology
AlgebraicGeometry.Scheme.Fppf

The category of flat, locally finitely presented schemes over the base.

Source context 4 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
def Fppf (S : Scheme.{u}) : Type (u + 1)
Source context 4 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
instance (S : Scheme.{u}) : Category.{u} S.Fppf
Source context 6 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
namespace Fppf
variable (S : Scheme.{u})
instance (U : S.Fppf) : Flat U.hom
Source context 6 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
namespace Fppf
variable (S : Scheme.{u})
instance (U : S.Fppf) : LocallyOfFinitePresentation U.hom
AlgebraicGeometry.Scheme.Fppf.mk

View a flat, locally finitely presented morphism as an object of the small fppf site.

Source context 7 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
namespace Fppf
variable (S : Scheme.{u})
variable {S} in
def mk {X : Scheme.{u}} (f : X ⟶ S) [Flat f]
    [LocallyOfFinitePresentation f] : S.Fppf
AlgebraicGeometry.Scheme.Fppf.forget

Forget the flatness and finite-presentation conditions on a scheme over the base.

Source context 7 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
namespace Fppf
variable (S : Scheme.{u})
variable {S} in
def forget : S.Fppf ⥤ Over S
Source context 7 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
namespace Fppf
variable (S : Scheme.{u})
variable {S} in
instance : (Fppf.forget S).Full
Source context 7 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
namespace Fppf
variable (S : Scheme.{u})
variable {S} in
instance : (Fppf.forget S).Faithful
AlgebraicGeometry.Scheme.smallFppfTopology

The Grothendieck topology on the small fppf site of a scheme.

Source context 4 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
def smallFppfTopology (S : Scheme.{u}) : GrothendieckTopology S.Fppf
AlgebraicGeometry.Scheme.overGrothendieckTopology_fppfProperty_eq
Source context 4 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
theorem overGrothendieckTopology_fppfProperty_eq (S : Scheme.{u}) :
    S.overGrothendieckTopology fppfProperty = fppfTopology.over S
Source context 4 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
instance (S : Scheme.{u}) :
    (Fppf.forget S).LocallyCoverDense (fppfTopology.over S)
AlgebraicGeometry.Scheme.smallFppfTopology_eq_restrictedTopology
Source context 4 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
theorem smallFppfTopology_eq_restrictedTopology (S : Scheme.{u}) :
    smallFppfTopology S = (Fppf.forget S).restrictedTopology (fppfTopology.over S)
Source context 4 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
instance (S : Scheme.{u}) :
    (Fppf.forget S).IsCocontinuous (smallFppfTopology S) (fppfTopology.over S)
AlgebraicGeometry.Scheme.fppfTerminal

The identity morphism, as an object of the small fppf site.

Source context 4 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
def fppfTerminal (S : Scheme.{u}) : S.Fppf
AlgebraicGeometry.Scheme.fppfTerminalIsTerminal

The identity morphism is terminal in the small fppf site.

Source context 4 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
def fppfTerminalIsTerminal (S : Scheme.{u}) : IsTerminal (fppfTerminal S)
Source context 4 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
instance (S : Scheme.{u}) : HasTerminal S.Fppf
AlgebraicGeometry.Scheme.hasSheafify_smallFppfTopology
Source context 5 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
instance hasSheafify_smallFppfTopology : HasSheafify (smallFppfTopology S) Ab.{u + 1}
AlgebraicGeometry.Scheme.abelian_sheaf_smallFppfTopology
Source context 5 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
instance abelian_sheaf_smallFppfTopology :
    Abelian (Sheaf (smallFppfTopology S) Ab.{u + 1})
AlgebraicGeometry.Scheme.isGrothendieckAbelian_sheaf_smallFppfTopology
Source context 5 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
instance isGrothendieckAbelian_sheaf_smallFppfTopology :
    IsGrothendieckAbelian.{u + 1} (Sheaf (smallFppfTopology S) Ab.{u + 1})
AlgebraicGeometry.Scheme.hasExt_sheaf_smallFppfTopology
Source context 5 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
instance hasExt_sheaf_smallFppfTopology :
    HasExt.{u + 1} (Sheaf (smallFppfTopology S) Ab.{u + 1})
AlgebraicGeometry.Scheme.fppfCohomology

The degree n cohomology of an abelian sheaf on the small fppf site.

Source context 5 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
def fppfCohomology (F : Sheaf (smallFppfTopology S) Ab.{u + 1}) (n : ℕ) :
    Type (u + 1)
Source context 5 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
instance (F : Sheaf (smallFppfTopology S) Ab.{u + 1}) (n : ℕ) :
    AddCommGroup (fppfCohomology S F n)
Source context 5 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
instance : (Functor.const (S.Fppf)ᵒᵖ : Ab.{u + 1} ⥤ ((S.Fppf)ᵒᵖ ⥤ Ab.{u + 1})).Additive where
  map_add := by intros; ext; rfl
Source context 5 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
instance : (constantSheaf (smallFppfTopology S) Ab.{u + 1}).Additive
AlgebraicGeometry.Scheme.homULiftIntAddEquiv

Identify morphisms from the lifted integers with elements of an abelian group.

Source context 6 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
universe w in
def homULiftIntAddEquiv (A : Ab.{w}) :
    (AddCommGrpCat.of (ULift.{w} ℤ) ⟶ A) ≃+ A
AlgebraicGeometry.Scheme.sheafHZeroAddEquiv

Identify degree-zero sheaf cohomology with sections on the terminal object.

Source context 7 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
universe w in
open Abelian in
def sheafHZeroAddEquiv (F : Sheaf (smallFppfTopology S) Ab.{u + 1}) :
    F.H 0 ≃+ F.obj.obj (op (fppfTerminal S))
AlgebraicGeometry.Scheme.fppfCohomologyZeroAddEquiv

Identify degree-zero fppf cohomology with global sections.

Source context 7 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
universe w in
open Abelian in
def fppfCohomologyZeroAddEquiv (F : Sheaf (smallFppfTopology S) Ab.{u + 1}) :
    fppfCohomology S F 0 ≃+ F.obj.obj (op (fppfTerminal S))
AlgebraicGeometry.Scheme.sheafHMap

The additive map on sheaf cohomology induced by a sheaf morphism.

Source context 7 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
universe w in
open Abelian in
def sheafHMap {F G : Sheaf (smallFppfTopology S) Ab.{u + 1}} (φ : F ⟶ G)
    (n : ℕ) : F.H n →+ G.H n
AlgebraicGeometry.Scheme.fppfCohomologyMap

The map on fppf cohomology induced by a morphism of abelian sheaves.

Source context 7 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
universe w in
open Abelian in
def fppfCohomologyMap {F G : Sheaf (smallFppfTopology S) Ab.{u + 1}} (φ : F ⟶ G)
    (n : ℕ) : fppfCohomology S F n →+ fppfCohomology S G n
AlgebraicGeometry.Scheme.sheafHMap_id
Source context 7 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
universe w in
open Abelian in
theorem sheafHMap_id {F : Sheaf (smallFppfTopology S) Ab.{u + 1}} (n : ℕ)
    (α : F.H n) :
    sheafHMap S (𝟙 F) n α = α
AlgebraicGeometry.Scheme.fppfCohomologyMap_id
Source context 7 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
universe w in
open Abelian in
theorem fppfCohomologyMap_id {F : Sheaf (smallFppfTopology S) Ab.{u + 1}} (n : ℕ)
    (α : fppfCohomology S F n) :
    fppfCohomologyMap S (𝟙 F) n α = α
AlgebraicGeometry.Scheme.sheafHMap_comp
Source context 7 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
universe w in
open Abelian in
theorem sheafHMap_comp {F G H' : Sheaf (smallFppfTopology S) Ab.{u + 1}}
    (φ : F ⟶ G) (ψ : G ⟶ H') (n : ℕ) (α : F.H n) :
    sheafHMap S (φ ≫ ψ) n α = sheafHMap S ψ n (sheafHMap S φ n α)
AlgebraicGeometry.Scheme.fppfCohomologyMap_comp
Source context 7 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
universe w in
open Abelian in
theorem fppfCohomologyMap_comp {F G H' : Sheaf (smallFppfTopology S) Ab.{u + 1}}
    (φ : F ⟶ G) (ψ : G ⟶ H') (n : ℕ) (α : fppfCohomology S F n) :
    fppfCohomologyMap S (φ ≫ ψ) n α = fppfCohomologyMap S ψ n (fppfCohomologyMap S φ n α)
AlgebraicGeometry.Scheme.fppfCohomologyFunctor

Degree n fppf cohomology as a functor to abelian groups.

Source context 6 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
universe w in
def fppfCohomologyFunctor (n : ℕ) :
    Sheaf (smallFppfTopology S) Ab.{u + 1} ⥤ Ab.{u + 1}
AlgebraicGeometry.Scheme.fppfCohomologyFunctor_obj_carrier
Source context 6 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
universe w in
theorem fppfCohomologyFunctor_obj_carrier (n : ℕ) (F : Sheaf (smallFppfTopology S) Ab.{u + 1}) :
    ((fppfCohomologyFunctor S n).obj F : Type (u + 1)) = F.H n
AlgebraicGeometry.Scheme.fppfBigToOverRestriction

Restrict a sheaf on the big fppf site to schemes over the fixed base.

Source context 6 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
universe w in
def fppfBigToOverRestriction :
    Sheaf fppfTopology.{u} Ab.{u + 1} ⥤ Sheaf (fppfTopology.{u}.over S) Ab.{u + 1}
AlgebraicGeometry.Scheme.fppfSmallToOverPushforward

Push a sheaf on the small fppf site to the fppf over-site.

Source context 6 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
universe w in
def fppfSmallToOverPushforward :
    Sheaf (smallFppfTopology S) Ab.{u + 1} ⥤ Sheaf (fppfTopology.{u}.over S) Ab.{u + 1}
AlgebraicGeometry.Scheme.gate_zero_sheaf_subsingleton
Source context 7 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
universe w in
open ZeroObject in
theorem gate_zero_sheaf_subsingleton (n : ℕ) :
    Subsingleton (fppfCohomology S (0 : Sheaf (smallFppfTopology S) Ab.{u + 1}) n)
AlgebraicGeometry.Scheme.gate_H0_nontrivial_of_sections_nontrivial
Source context 6 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
universe w in
theorem gate_H0_nontrivial_of_sections_nontrivial (F : Sheaf (smallFppfTopology S) Ab.{u + 1})
    (h : Nontrivial (F.obj.obj (op (fppfTerminal S)))) :
    Nontrivial (fppfCohomology S F 0)
AlgebraicGeometry.Scheme.gate_H0_equiv_fires_on_zero_sheaf
Source context 7 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
universe w in
open ZeroObject in
theorem gate_H0_equiv_fires_on_zero_sheaf :
    Subsingleton
      (((0 : Sheaf (smallFppfTopology S) Ab.{u + 1}).obj.obj (op (fppfTerminal S))) :
        Type (u + 1))
AlgebraicGeometry.Scheme.specInt

The spectrum of the integers.

Source context 7 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
universe w in
section SpecInt
abbrev specInt : Scheme.{0}
AlgebraicGeometry.Scheme.fppfCohomologySpecIntZeroAddEquiv

Identify degree-zero fppf cohomology over the integers with global sections.

Source context 8 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
universe w in
section SpecInt
open Abelian in
def fppfCohomologySpecIntZeroAddEquiv
    (F : Sheaf (smallFppfTopology specInt) Ab.{1}) :
    fppfCohomology specInt F 0 ≃+ F.obj.obj (op (fppfTerminal specInt))
AlgebraicGeometry.Scheme.gate_specInt_H1_zero_sheaf_subsingleton
Source context 8 commands

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

universe u
open CategoryTheory CategoryTheory.Limits Opposite
namespace AlgebraicGeometry.Scheme
attribute [instance] fppfProperty_isStableUnderBaseChange fppfProperty_isMultiplicative
  fppfProperty_isStableUnderComposition fppfProperty_respectsIso
  fppfProperty_containsIdentities fppfProperty_hasPullbacks
variable (S : Scheme.{u})
universe w in
section SpecInt
open ZeroObject in
theorem gate_specInt_H1_zero_sheaf_subsingleton :
    Subsingleton (fppfCohomology specInt (0 : Sheaf (smallFppfTopology specInt) Ab.{1}) 1)