Module

Topology.lean

Nyll.ClassFieldTheory.AlgebraicNumberTheory.Idele.Topology
12 declarations indexed from sourceView source ↗

The idele topology

The idele group I_K carries the restricted-product topology. This file records the topological-group structure and the continuity of every local component map.

Declarations

The local integral-unit subgroup is open in the multiplicative group of a finite completion.

Source context 4 commands

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

open scoped NumberField
open NumberField IsDedekindDomain
noncomputable section
variable (K : Type*) [Field K] [NumberField K]
theorem isOpen_finiteLocalUnits (v : HeightOneSpectrum (𝓞 K)) :
    IsOpen
      ((v.adicCompletionIntegers K).units :
        Set (v.adicCompletion K)ˣ)
Source context 4 commands

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

open scoped NumberField
open NumberField IsDedekindDomain
noncomputable section
variable (K : Type*) [Field K] [NumberField K]
instance finiteLocalUnitsOpen :
    Fact (∀ v : HeightOneSpectrum (𝓞 K),
      IsOpen
        ((v.adicCompletionIntegers K).units :
          Set (v.adicCompletion K)ˣ))
Source context 4 commands

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

open scoped NumberField
open NumberField IsDedekindDomain
noncomputable section
variable (K : Type*) [Field K] [NumberField K]
instance finiteIdeleGroupIsTopologicalGroup :
    IsTopologicalGroup (FiniteIdeleGroup K)
Source context 4 commands

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

open scoped NumberField
open NumberField IsDedekindDomain
noncomputable section
variable (K : Type*) [Field K] [NumberField K]
instance ideleGroupIsTopologicalGroup :
    IsTopologicalGroup (IdeleGroup K)
Source context 4 commands

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

open scoped NumberField
open NumberField IsDedekindDomain
noncomputable section
variable (K : Type*) [Field K] [NumberField K]
instance finiteIdeleGroupT2Space :
    T2Space (FiniteIdeleGroup K)
Source context 4 commands

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

open scoped NumberField
open NumberField IsDedekindDomain
noncomputable section
variable (K : Type*) [Field K] [NumberField K]
instance infiniteAdeleRingT2Space :
    T2Space (NumberField.InfiniteAdeleRing K)
Source context 4 commands

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

open scoped NumberField
open NumberField IsDedekindDomain
noncomputable section
variable (K : Type*) [Field K] [NumberField K]
instance infiniteIdeleGroupT2Space :
    T2Space (InfiniteIdeleGroup K)
Source context 4 commands

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

open scoped NumberField
open NumberField IsDedekindDomain
noncomputable section
variable (K : Type*) [Field K] [NumberField K]
instance ideleGroupT2Space :
    T2Space (IdeleGroup K)
IdeleGroup.infiniteComponentContinuous

Evaluation at an archimedean place is a continuous homomorphism.

Source context 6 commands

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

open scoped NumberField
open NumberField IsDedekindDomain
noncomputable section
variable (K : Type*) [Field K] [NumberField K]
namespace IdeleGroup
variable {K}
def infiniteComponentContinuous (v : InfinitePlace K) :
    IdeleGroup K →ₜ* v.Completionˣ where
  __ := infiniteComponent v
  continuous_toFun :=
    (continuous_apply v).comp
      (ContinuousMulEquiv.piUnits.continuous.comp continuous_fst)
IdeleGroup.finiteComponentContinuous

Evaluation at a finite place is a continuous homomorphism.

Source context 6 commands

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

open scoped NumberField
open NumberField IsDedekindDomain
noncomputable section
variable (K : Type*) [Field K] [NumberField K]
namespace IdeleGroup
variable {K}
def finiteComponentContinuous (v : HeightOneSpectrum (𝓞 K)) :
    IdeleGroup K →ₜ* (v.adicCompletion K)ˣ where
  __ := finiteComponent v
  continuous_toFun :=
    (RestrictedProduct.continuous_eval v).comp continuous_snd
IdeleGroup.infiniteComponentContinuous_apply
Source context 6 commands

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

open scoped NumberField
open NumberField IsDedekindDomain
noncomputable section
variable (K : Type*) [Field K] [NumberField K]
namespace IdeleGroup
variable {K}
theorem infiniteComponentContinuous_apply
    (a : IdeleGroup K) (v : InfinitePlace K) :
    infiniteComponentContinuous v a =
      ContinuousMulEquiv.piUnits a.1 v
IdeleGroup.finiteComponentContinuous_apply
Source context 6 commands

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

open scoped NumberField
open NumberField IsDedekindDomain
noncomputable section
variable (K : Type*) [Field K] [NumberField K]
namespace IdeleGroup
variable {K}
theorem finiteComponentContinuous_apply
    (a : IdeleGroup K) (v : HeightOneSpectrum (𝓞 K)) :
    finiteComponentContinuous v a = a.2 v