Module

QuasicoherentKernelGlobal.lean

Nyll.SchemeTheory.Modules.QuasicoherentKernelGlobal
3 declarations indexed from sourceView source ↗

Quasicoherence of kernels on schemes

Restriction preserves the actual categorical kernel. Affine kernel quasicoherence supplies the hypotheses of the shared affine-presentation criterion, which constructs the global quasicoherent data.

Imports11
  • Nyll.SchemeTheory.Modules.QuasicoherentKernel
  • Nyll.SchemeTheory.Modules.QuasicoherentLocal
  • Mathlib.AlgebraicGeometry.Modules.Tilde
  • Mathlib.AlgebraicGeometry.Modules.Sheaf
  • Mathlib.AlgebraicGeometry.AffineScheme
  • Mathlib.Algebra.Category.ModuleCat.Sheaf.Quasicoherent
  • Mathlib.Algebra.Category.ModuleCat.Sheaf.PullbackContinuous
  • Mathlib.Algebra.Category.ModuleCat.Presheaf.Pullback
  • Mathlib.CategoryTheory.Limits.Preserves.Shapes.Kernels
  • Mathlib.Topology.Sheaves.Module
  • Mathlib.CategoryTheory.Adjunction.Limits
Imported by3

Declarations

AlgebraicGeometry.Scheme.Modules.preservesFiniteLimits_restrictFunctor

Restriction along an open immersion preserves finite limits, by the actual native sheaf pushforward adjunction defining the restriction.

Source context 4 commands

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

noncomputable section
universe u
open CategoryTheory Limits TopologicalSpace
namespace AlgebraicGeometry.Scheme.Modules
theorem preservesFiniteLimits_restrictFunctor
    {X Y : Scheme.{u}} (f : X ⟶ Y) [IsOpenImmersion f] :
    PreservesFiniteLimits (restrictFunctor f)
AlgebraicGeometry.Scheme.Modules.restrictFunctor_preservesZeroMorphisms_kernel
Source context 4 commands

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

noncomputable section
universe u
open CategoryTheory Limits TopologicalSpace
namespace AlgebraicGeometry.Scheme.Modules
instance restrictFunctor_preservesZeroMorphisms_kernel
    {X Y : Scheme.{u}} (f : X ⟶ Y) [IsOpenImmersion f] :
    (restrictFunctor f).PreservesZeroMorphisms where
  map_zero _ _ := rfl
AlgebraicGeometry.Scheme.Modules.isQuasicoherent_kernel

The actual categorical kernel of any morphism of quasicoherent modules on a scheme is quasicoherent. No separation or compactness assumption is needed.

Source context 4 commands

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

noncomputable section
universe u
open CategoryTheory Limits TopologicalSpace
namespace AlgebraicGeometry.Scheme.Modules
theorem isQuasicoherent_kernel
    {X : Scheme.{u}} {M N : X.Modules}
    [M.IsQuasicoherent] [N.IsQuasicoherent] (φ : M ⟶ N) :
    (kernel φ).IsQuasicoherent