Module

NativeNormalizationRadical.lean

Nyll.EtaleFundamentalGroups.Inertia.NativeNormalizationRadical
2 declarations indexed from sourceView source ↗

Ambient integral radicals in the actual native subalgebra normalization

Literal membership in the subalgebra and the already proved ambient integrality construct the actual normalization element. Its power equation is inherited through the two subtype inclusions. No fraction-field tower or chosen absolute prime is opened in this owner.

Declarations

EtaleFundamentalGroups.Inertia.nativeNormalizationElement

An actual integral ambient element in the selected subalgebra gives an element of its literal native normalization.

Source context 5 commands

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

noncomputable section
namespace EtaleFundamentalGroups.Inertia
open SchemeTheory
universe u v
variable {A : Type u} {Ω : Type v} [CommRing A] [CommRing Ω] [Algebra A Ω]
def nativeNormalizationElement
    (S : Subalgebra A Ω) (α : Ω) (hmem : α ∈ S) (hint : IsIntegral A α) :
    subalgebraNormalizationCommAlgCat S
EtaleFundamentalGroups.Inertia.nativeNormalizationElement_pow

The original radical equation holds in the native normalization with its computed coefficient map.

Source context 5 commands

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

noncomputable section
namespace EtaleFundamentalGroups.Inertia
open SchemeTheory
universe u v
variable {A : Type u} {Ω : Type v} [CommRing A] [CommRing Ω] [Algebra A Ω]
theorem nativeNormalizationElement_pow
    (S : Subalgebra A Ω) (α : Ω) (hmem : α ∈ S) (hint : IsIntegral A α)
    (n : ℕ) (π : A) (hpow : α ^ n = algebraMap A Ω π) :
    (nativeNormalizationElement S α hmem hint) ^ n =
      commAlgCoefficientMap (subalgebraNormalizationCommAlgCat S) π