Module

ActualFiniteNormalizationLocalTower.lean

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

Local maps in finite normalization towers

Constructs the local ring map at nested finite normalization primes and establishes its injectivity under the DVR and Galois hypotheses.

Declarations

EtaleFundamentalGroups.Inertia.actualFiniteNormalizationTowerLocalRingMap

The literal local ring map at two nested actual finite primes.

Source context 5 commands

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

noncomputable section
namespace EtaleFundamentalGroups.Inertia
open SchemeTheory
universe u v w
variable (A : Type u) (K : Type v) (L : Type w)
  [CommRing A] [Field K] [Field L]
  [Algebra A K] [Algebra K L] [Algebra A L] [IsScalarTower A K L]
  (Q : Ideal (normalizationCommAlgCat A L)) [Q.IsPrime]
def actualFiniteNormalizationTowerLocalRingMap
    (E F : FiniteGaloisIntermediateField K L) (h : E ≤ F) :
    letI := finiteAbsoluteNormalizationPrime_isPrime A K L Q E
    letI := finiteAbsoluteNormalizationPrime_isPrime A K L Q F
    Localization.AtPrime (finiteAbsoluteNormalizationPrime A K L Q E) →+*
      Localization.AtPrime (finiteAbsoluteNormalizationPrime A K L Q F) := by
  letI := finiteAbsoluteNormalizationPrime_isPrime A K L Q E
  letI := finiteAbsoluteNormalizationPrime_isPrime A K L Q F
  exact Localization.localRingHom
    (finiteAbsoluteNormalizationPrime A K L Q E)
    (finiteAbsoluteNormalizationPrime A K L Q F)
    (actualFiniteNormalizationTowerRingMap A K L E F h)
    (actualFiniteNormalizationPrime_tower A K L Q E F h)
EtaleFundamentalGroups.Inertia.actualFiniteNormalizationTowerLocalRingMap_injective

The actual map of finite local normalizations is injective.

Source context 5 commands

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

noncomputable section
namespace EtaleFundamentalGroups.Inertia
open SchemeTheory
universe u v w
variable (A : Type u) (K : Type v) (L : Type w)
  [CommRing A] [Field K] [Field L]
  [Algebra A K] [Algebra K L] [Algebra A L] [IsScalarTower A K L]
  (Q : Ideal (normalizationCommAlgCat A L)) [Q.IsPrime]
theorem actualFiniteNormalizationTowerLocalRingMap_injective
    [IsDomain A] [IsDiscreteValuationRing A] [IsFractionRing A K] [IsGalois K L]
    (E F : FiniteGaloisIntermediateField K L) (h : E ≤ F) :
    Function.Injective (actualFiniteNormalizationTowerLocalRingMap A K L Q E F h).toFun