Module

ModPGroupDerivative.lean

Nyll.ProCGroups.ProP.Fox.ModPGroupDerivative
7 declarations indexed from sourceView source ↗

Mod-p Fox derivatives on finite pro-p presentation groups

Reducing every coordinate of the integral completed Fox derivative modulo p gives a continuous crossed homomorphism into the mod-p completed group algebra coordinates. Its coefficient is the completed group-like element of the presentation quotient.

Declarations

ClassFieldTower.ProP.PresentationModPFoxCoordinates

Mod-p completed Fox-coordinate vectors for the chosen finite basis.

Source context 11 commands

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

open scoped Topology
namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
abbrev PresentationModPFoxCoordinates
ClassFieldTower.ProP.presentationModPFoxCoefficient

The mod-p group-like coefficient attached to the presentation quotient.

Source context 11 commands

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

open scoped Topology
namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
def presentationModPFoxCoefficient
    (P : FiniteProPPresentation p d r sourceData G) :
    sourceData.carrier →* ModPCompletedGroupAlgebra p G
ClassFieldTower.ProP.presentationModPFoxCoefficient_apply

The mod-p coefficient is the completed group-like element of the presentation quotient.

Source context 11 commands

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

open scoped Topology
namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
theorem presentationModPFoxCoefficient_apply
    (P : FiniteProPPresentation p d r sourceData G)
    (f : sourceData.carrier) :
    presentationModPFoxCoefficient P f =
      completedGroupAlgebraOfInClass
        (FiniteGroupClass.pGroup p) (ZMod p) G (P.quotient f)
ClassFieldTower.ProP.presentationModPFoxDerivative

The presentation Fox derivative with every coordinate reduced modulo p, bundled with its crossed-product law.

Source context 11 commands

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

open scoped Topology
namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
def presentationModPFoxDerivative
    (P : FiniteProPPresentation p d r sourceData G) :
    ScalarCrossedHom
      (presentationModPFoxCoefficient P)
      (PresentationModPFoxCoordinates (p := p) (d := d) (G := G)) where
  toFun f i :=
    modPCoefficientReduction p G (presentationFoxDerivative P f i)
  map_mul' f g := by
    funext i
    change modPCoefficientReduction p G
        (presentationFoxDerivative P (f * g) i) =
      modPCoefficientReduction p G (presentationFoxDerivative P f i) +
        presentationModPFoxCoefficient P f *
          modPCoefficientReduction p G (presentationFoxDerivative P g i)
    rw [ScalarCrossedHom.map_mul]
    simp only [Pi.add_apply, Pi.smul_apply, map_add, map_mul, smul_eq_mul]
    rfl
ClassFieldTower.ProP.presentationModPFoxDerivative_apply

Evaluation of a mod-p Fox coordinate is coefficient reduction of the corresponding integral coordinate.

Source context 11 commands

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

open scoped Topology
namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
theorem presentationModPFoxDerivative_apply
    (P : FiniteProPPresentation p d r sourceData G)
    (f : sourceData.carrier) (i : ULift.{u} (Fin d)) :
    presentationModPFoxDerivative P f i =
      modPCoefficientReduction p G (presentationFoxDerivative P f i)
ClassFieldTower.ProP.continuous_presentationModPFoxDerivative

The coordinatewise mod-p presentation Fox derivative is continuous.

Source context 11 commands

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

open scoped Topology
namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
theorem continuous_presentationModPFoxDerivative
    (P : FiniteProPPresentation p d r sourceData G) :
    Continuous (presentationModPFoxDerivative P)
ClassFieldTower.ProP.presentationModPFoxDerivative_mul

The crossed-product law written with the presentation quotient's mod-p group-like coefficient.

Source context 11 commands

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

open scoped Topology
namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
theorem presentationModPFoxDerivative_mul
    (P : FiniteProPPresentation p d r sourceData G)
    (f g : sourceData.carrier) :
    presentationModPFoxDerivative P (f * g) =
      presentationModPFoxDerivative P f +
        completedGroupAlgebraOfInClass
            (FiniteGroupClass.pGroup p) (ZMod p) G (P.quotient f) •
          presentationModPFoxDerivative P g