Module

ExistsRayArtinModulusProjection.lean

Nyll.ClassFieldTheory.Theorems.ConductorsAndRayClassFields.ExistsRayArtinModulusProjection
3 declarations indexed from sourceView source ↗

Existence of a modulus-compatible ray class field embedding

Reducing the modulus yields an embedding of ray class field realizations that intertwines their Artin maps.

Declarations

ClassFieldTheory.rayArtin_prime_eq_arithmeticPrimeArtin
Source context 4 commands

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

open scoped NumberField
open NumberField IsDedekindDomain
noncomputable section
namespace ClassFieldTheory
theorem rayArtin_prime_eq_arithmeticPrimeArtin
    {K : Type} [Field K] [NumberField K]
    {m : RayClassModulus K} (R : RayClassFieldRealization K m)
    (v : HeightOneSpectrum (𝓞 K))
    (hv : v ∉ m.finitePart.support) :
    R.rayArtin (rayClassOfFinitePrime m v hv) =
      GlobalClassFieldTheory.GlobalClassFields.arithmeticFinitePlacePrimeArtin
        (K := K) (L := R.extension) v
ClassFieldTheory.rayClassFieldRealization_norm_range
Source context 4 commands

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

open scoped NumberField
open NumberField IsDedekindDomain
noncomputable section
namespace ClassFieldTheory
theorem rayClassFieldRealization_norm_range
    {K : Type} [Field K] [NumberField K]
    {m : RayClassModulus K} (R : RayClassFieldRealization K m) :
    (_root_.ideleClassNorm K R.extension).range =
      (GlobalClassFieldComparison.rayClassModulusToOriginal K m).congruenceSubgroup
ClassFieldTheory.exists_rayArtin_modulusProjection

A reduction of the modulus yields an embedding of any two ray-class-field realizations, and this embedding intertwines their Artin maps.

Source context 4 commands

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

open scoped NumberField
open NumberField IsDedekindDomain
noncomputable section
namespace ClassFieldTheory
theorem exists_rayArtin_modulusProjection
    {K : Type} [Field K] [NumberField K]
    {m n : RayClassModulus K} (hmn : m ≤ n)
    (Rm : RayClassFieldRealization K m)
    (Rn : RayClassFieldRealization K n) :
    ∃ f : Rm.extension →ₐ[K] Rn.extension,
      ∀ (x : RayClassGroup n) (y : Rm.extension),
        Rn.rayArtin x (f y) =
          f (Rm.rayArtin (rayClassIdealModulusProjection K hmn x) y)