Module

FiniteTypeValuationModel.lean

Nyll.Yamaguchi26AbfaithfulGalois.FieldExamples.FiniteTypeValuationModel
1 declaration indexed from sourceView source ↗

Finite-type models inside valuation rings

An essentially finite-type extension of a fraction field admits an integral finite-type model inside any valuation ring containing the base ring.

Imports3
  • Mathlib.FieldTheory.IntermediateField.Adjoin.Algebra
  • Mathlib.RingTheory.Localization.FractionRing
  • Mathlib.RingTheory.Valuation.ValuationSubring
Imported by2

Declarations

Yamaguchi26AbfaithfulGalois.finiteType_model_in_valuation

A finitely generated extension of a fraction field admits a finite type integral model inside any valuation ring containing the base ring.

Source context 2 commands

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

namespace Yamaguchi26AbfaithfulGalois
universe u v w
theorem finiteType_model_in_valuation
    (R : Type u) (F : Type v) (E : Type w)
    [CommRing R] [IsDomain R] [Field F] [Field E]
    [Algebra R F] [IsFractionRing R F] [Algebra F E] [Algebra R E]
    [IsScalarTower R F E] [Algebra.EssFiniteType F E]
    (V : ValuationSubring E) (hR : ∀ r : R, algebraMap R E r ∈ V) :
    ∃ A : Subalgebra R E, Algebra.FiniteType R A ∧ IsFractionRing A E ∧
      A.toSubring ≤ V.toSubring