EtaleFundamentalGroups.Inertia.actualTameCoordinate_at_stage
Evaluation at the degree of any finite stage recovers its canonical coordinate, through the SAME canonical quotient comparison.
Source context 5 commands
Surrounding namespaces, section variables, and local commands at this declaration.
namespace EtaleFundamentalGroups.Inertia
open SchemeTheory
universe u v w
attribute [local instance] Ideal.Quotient.field
variable (A : Type u) (K : Type v) (L : Type w)
[CommRing A] [IsDomain A] [IsDiscreteValuationRing 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 (normalizationCommAlgCat A L).carrier) [Q.IsMaximal]Lean source · statement
theorem actualTameCoordinate_at_stage
(E : FiniteGaloisIntermediateField K L)
(σ : (actualNormalizationInertiaGroup A K L Q).carrier) :
(actualTameCoordinate A K L Q
⟨actualFiniteStageTameIndex A K L Q E, E, rfl⟩).toFun σ =
(normalizationQuotientRootsEquiv A L Q
(actualFiniteStageTameOrder A K L Q E)).toFun
((actualFiniteTameCoordinate A K L Q E).hom'.toFun σ)