Module

MaximalEverywhereUnramifiedProPGalois.lean

Nyll.SawinTotallyRealTowers.UnramifiedProPRelationRank.Global.MaximalEverywhereUnramifiedProPGalois
10 declarations indexed from sourceView source ↗

The Galois group of the maximal everywhere-unramified pro-p extension

The maximal compositum is Galois because each proof-indexed candidate layer is either a finite Galois field or bottom, and arbitrary composita preserve separability and normality. The resulting automorphism group carries only the canonical Krull topology and profinite instances supplied by Mathlib; its pro-p property is deferred to the finite-support argument.

Declarations

ClassFieldTower.Martinet.isGalois_candidateLayer

For a fixed intermediate field, the proof-indexed candidate layer in the definition of maximalEverywhereUnramifiedProP is Galois. It is the field itself when all candidate properties hold and bottom otherwise.

Source context 4 commands

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

open scoped NumberField
noncomputable section
universe u
namespace ClassFieldTower.Martinet
theorem isGalois_candidateLayer
    (F : Type u) [Field F] [NumberField F]
    (p : ℕ) [Fact (Nat.Prime p)]
    (M : IntermediateField F (AlgebraicClosure F)) :
    IsGalois F
      ((⨆ (_ : FiniteDimensional F M)
          (_ : IsGalois F M)
          (_ : IsPGroup p (M ≃ₐ[F] M))
          (_ : NumberField M)
          (_ : IsEverywhereUnramified F M),
        M) : IntermediateField F (AlgebraicClosure F))
ClassFieldTower.Martinet.maximalEverywhereUnramifiedProP_isGalois

The maximal everywhere-unramified pro-p compositum is a Galois extension of the base field.

Source context 4 commands

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

open scoped NumberField
noncomputable section
universe u
namespace ClassFieldTower.Martinet
theorem maximalEverywhereUnramifiedProP_isGalois
    (F : Type u) [Field F] [NumberField F]
    (p : ℕ) [Fact (Nat.Prime p)] :
    IsGalois F (maximalEverywhereUnramifiedProP F p)
ClassFieldTower.Martinet.maximalEverywhereUnramifiedProP.instIsGalois

The canonical Galois instance for the maximal compositum.

Source context 4 commands

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

open scoped NumberField
noncomputable section
universe u
namespace ClassFieldTower.Martinet
instance maximalEverywhereUnramifiedProP.instIsGalois
    (F : Type u) [Field F] [NumberField F]
    (p : ℕ) [Fact (Nat.Prime p)] :
    IsGalois F (maximalEverywhereUnramifiedProP F p)
ClassFieldTower.Martinet.MaxEverywhereUnramifiedProPGaloisGroup

The automorphism group of the maximal everywhere-unramified pro-p compositum. Its pro-p property is established only after finite support.

Source context 4 commands

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

open scoped NumberField
noncomputable section
universe u
namespace ClassFieldTower.Martinet
def MaxEverywhereUnramifiedProPGaloisGroup
    (F : Type u) [Field F] [NumberField F]
    (p : ℕ) [Fact (Nat.Prime p)] : Type u
ClassFieldTower.Martinet.MaxEverywhereUnramifiedProPGaloisGroup.instGroup

The canonical group structure inherited from algebra automorphisms.

Source context 4 commands

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

open scoped NumberField
noncomputable section
universe u
namespace ClassFieldTower.Martinet
instance MaxEverywhereUnramifiedProPGaloisGroup.instGroup
    (F : Type u) [Field F] [NumberField F]
    (p : ℕ) [Fact (Nat.Prime p)] :
    Group (MaxEverywhereUnramifiedProPGaloisGroup F p)
ClassFieldTower.Martinet.MaxEverywhereUnramifiedProPGaloisGroup.instTopologicalSpace

The canonical Krull topology inherited from algebra automorphisms.

Source context 4 commands

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

open scoped NumberField
noncomputable section
universe u
namespace ClassFieldTower.Martinet
instance MaxEverywhereUnramifiedProPGaloisGroup.instTopologicalSpace
    (F : Type u) [Field F] [NumberField F]
    (p : ℕ) [Fact (Nat.Prime p)] :
    TopologicalSpace (MaxEverywhereUnramifiedProPGaloisGroup F p)
ClassFieldTower.Martinet.MaxEverywhereUnramifiedProPGaloisGroup.instIsTopologicalGroup

The canonical topological-group structure for the Krull topology.

Source context 4 commands

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

open scoped NumberField
noncomputable section
universe u
namespace ClassFieldTower.Martinet
instance MaxEverywhereUnramifiedProPGaloisGroup.instIsTopologicalGroup
    (F : Type u) [Field F] [NumberField F]
    (p : ℕ) [Fact (Nat.Prime p)] :
    IsTopologicalGroup (MaxEverywhereUnramifiedProPGaloisGroup F p)
ClassFieldTower.Martinet.MaxEverywhereUnramifiedProPGaloisGroup.instCompactSpace

Compactness inherited from the profinite Galois-group construction.

Source context 4 commands

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

open scoped NumberField
noncomputable section
universe u
namespace ClassFieldTower.Martinet
instance MaxEverywhereUnramifiedProPGaloisGroup.instCompactSpace
    (F : Type u) [Field F] [NumberField F]
    (p : ℕ) [Fact (Nat.Prime p)] :
    CompactSpace (MaxEverywhereUnramifiedProPGaloisGroup F p)
ClassFieldTower.Martinet.MaxEverywhereUnramifiedProPGaloisGroup.instT2Space

Hausdorffness inherited from the Krull topology.

Source context 4 commands

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

open scoped NumberField
noncomputable section
universe u
namespace ClassFieldTower.Martinet
instance MaxEverywhereUnramifiedProPGaloisGroup.instT2Space
    (F : Type u) [Field F] [NumberField F]
    (p : ℕ) [Fact (Nat.Prime p)] :
    T2Space (MaxEverywhereUnramifiedProPGaloisGroup F p)
ClassFieldTower.Martinet.MaxEverywhereUnramifiedProPGaloisGroup.instTotallyDisconnectedSpace

Total disconnectedness inherited from the Krull topology.

Source context 4 commands

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

open scoped NumberField
noncomputable section
universe u
namespace ClassFieldTower.Martinet
instance MaxEverywhereUnramifiedProPGaloisGroup.instTotallyDisconnectedSpace
    (F : Type u) [Field F] [NumberField F]
    (p : ℕ) [Fact (Nat.Prime p)] :
    TotallyDisconnectedSpace
      (MaxEverywhereUnramifiedProPGaloisGroup F p)