Module

InvariantPrimeLocalizationMap.lean

Nyll.EtaleFundamentalGroups.Inertia.InvariantPrimeLocalizationMap
7 declarations indexed from sourceView source ↗

The literal inertia-invariant prime localization maps to the normalization

The fixed subalgebra is computed using the original normalization inertia action. Its contracted-prime localization and native map to the normalization prime localization are the already constructed generic objects and RingHoms. The proved generic coefficient square gives the original base square directly.

The source computes the same actual localization used in 0BSU: the prime is the comap of Q under the inclusion of its original inertia-fixed subalgebra. No invariant/stalk comparison, alternate action, or compatibility premise is introduced. The finite-stage image and whole invariant-image results remain separate.

Declarations

EtaleFundamentalGroups.Inertia.normalizationInertiaFixedSubalgebra

The existing actual fixed subalgebra, with its original canonical normalization action. This closes its action data before taking localizations.

Source context 6 commands

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

noncomputable section
namespace EtaleFundamentalGroups.Inertia
open SchemeTheory EtaleFundamentalGroups.StrictHenselian
universe u v w
attribute [local instance] normalizationInertiaImageAction normalizationInertiaCoefficientCommClass
variable (A : Type u) (K : Type v) (L : Type w)
    [CommRing A] [Field K] [Field L]
    [Algebra A K] [IsFractionRing A K]
    [Algebra K L] [Algebra A L] [IsScalarTower A K L] [IsGalois K L]
    (Q : Ideal (integralClosure A L))
def normalizationInertiaFixedSubalgebra : Subalgebra A (integralClosure A L)
EtaleFundamentalGroups.Inertia.inertiaInvariantPrimeLocalization

The literal localization of the original inertia-fixed subalgebra at the contraction of Q, with its native commutative ring.

Source context 7 commands

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

noncomputable section
namespace EtaleFundamentalGroups.Inertia
open SchemeTheory EtaleFundamentalGroups.StrictHenselian
universe u v w
attribute [local instance] normalizationInertiaImageAction normalizationInertiaCoefficientCommClass
variable (A : Type u) (K : Type v) (L : Type w)
    [CommRing A] [Field K] [Field L]
    [Algebra A K] [IsFractionRing A K]
    [Algebra K L] [Algebra A L] [IsScalarTower A K L] [IsGalois K L]
    (Q : Ideal (integralClosure A L))
variable [Q.IsPrime]
def inertiaInvariantPrimeLocalization : CommRingCat.{w}
EtaleFundamentalGroups.Inertia.inertiaInvariantPrimeLocalizationMap

The actual native localized inclusion into the original normalization prime localization.

Source context 7 commands

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

noncomputable section
namespace EtaleFundamentalGroups.Inertia
open SchemeTheory EtaleFundamentalGroups.StrictHenselian
universe u v w
attribute [local instance] normalizationInertiaImageAction normalizationInertiaCoefficientCommClass
variable (A : Type u) (K : Type v) (L : Type w)
    [CommRing A] [Field K] [Field L]
    [Algebra A K] [IsFractionRing A K]
    [Algebra K L] [Algebra A L] [IsScalarTower A K L] [IsGalois K L]
    (Q : Ideal (integralClosure A L))
variable [Q.IsPrime]
def inertiaInvariantPrimeLocalizationMap :
    inertiaInvariantPrimeLocalization A K L Q →+* Localization.AtPrime Q
EtaleFundamentalGroups.Inertia.inertiaInvariantPrimeLocalizationBaseMap

The original base map to the actual inertia-invariant localization, computed through its genuine coefficient inclusion.

Source context 7 commands

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

noncomputable section
namespace EtaleFundamentalGroups.Inertia
open SchemeTheory EtaleFundamentalGroups.StrictHenselian
universe u v w
attribute [local instance] normalizationInertiaImageAction normalizationInertiaCoefficientCommClass
variable (A : Type u) (K : Type v) (L : Type w)
    [CommRing A] [Field K] [Field L]
    [Algebra A K] [IsFractionRing A K]
    [Algebra K L] [Algebra A L] [IsScalarTower A K L] [IsGalois K L]
    (Q : Ideal (integralClosure A L))
variable [Q.IsPrime]
def inertiaInvariantPrimeLocalizationBaseMap :
    A →+* inertiaInvariantPrimeLocalization A K L Q
EtaleFundamentalGroups.Inertia.inertiaInvariantPrimeLocalizationMap_comp_base

The native localized invariant inclusion extends precisely the original base map to the normalization prime localization.

Source context 7 commands

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

noncomputable section
namespace EtaleFundamentalGroups.Inertia
open SchemeTheory EtaleFundamentalGroups.StrictHenselian
universe u v w
attribute [local instance] normalizationInertiaImageAction normalizationInertiaCoefficientCommClass
variable (A : Type u) (K : Type v) (L : Type w)
    [CommRing A] [Field K] [Field L]
    [Algebra A K] [IsFractionRing A K]
    [Algebra K L] [Algebra A L] [IsScalarTower A K L] [IsGalois K L]
    (Q : Ideal (integralClosure A L))
variable [Q.IsPrime]
theorem inertiaInvariantPrimeLocalizationMap_comp_base :
    (inertiaInvariantPrimeLocalizationMap A K L Q).comp
        (inertiaInvariantPrimeLocalizationBaseMap A K L Q) =
      integralClosurePrimeBaseMap A L Q
EtaleFundamentalGroups.Inertia.inertiaInvariantPrimeLocalizationAlgebra

The actual invariant localization with the same native algebra used by its finite-level coefficient maps.

Source context 7 commands

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

noncomputable section
namespace EtaleFundamentalGroups.Inertia
open SchemeTheory EtaleFundamentalGroups.StrictHenselian
universe u v w
attribute [local instance] normalizationInertiaImageAction normalizationInertiaCoefficientCommClass
variable (A : Type u) (K : Type v) (L : Type w)
    [CommRing A] [Field K] [Field L]
    [Algebra A K] [IsFractionRing A K]
    [Algebra K L] [Algebra A L] [IsScalarTower A K L] [IsGalois K L]
    (Q : Ideal (integralClosure A L))
variable [Q.IsPrime]
def inertiaInvariantPrimeLocalizationAlgebra : CommAlgCat.{w} A
EtaleFundamentalGroups.Inertia.inertiaInvariantPrimeLocalizationBaseMap_eq_algebraMap

The previously constructed base RingHom is exactly the native algebra map on the actual invariant localization.

Source context 7 commands

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

noncomputable section
namespace EtaleFundamentalGroups.Inertia
open SchemeTheory EtaleFundamentalGroups.StrictHenselian
universe u v w
attribute [local instance] normalizationInertiaImageAction normalizationInertiaCoefficientCommClass
variable (A : Type u) (K : Type v) (L : Type w)
    [CommRing A] [Field K] [Field L]
    [Algebra A K] [IsFractionRing A K]
    [Algebra K L] [Algebra A L] [IsScalarTower A K L] [IsGalois K L]
    (Q : Ideal (integralClosure A L))
variable [Q.IsPrime]
theorem inertiaInvariantPrimeLocalizationBaseMap_eq_algebraMap :
    (inertiaInvariantPrimeLocalizationBaseMap A K L Q :
        A →+* inertiaInvariantPrimeLocalizationAlgebra A K L Q) =
      algebraMap A (inertiaInvariantPrimeLocalizationAlgebra A K L Q)