Module

InitialForm.lean

Nyll.ProCGroups.ProP.Presentation.InitialForm
7 declarations indexed from sourceView source ↗

Initial forms in the augmentation filtration

The degree-n initial form is constructed in the concrete quotient Iⁿ/Iⁿ⁺¹. A supplied depth witness produces the numerator element, and the quotient criterion identifies vanishing with membership one layer deeper.

Declarations

ClassFieldTower.ProP.nextClosedAugmentationLayerIn

The next closed augmentation layer, viewed inside the current layer.

Source context 7 commands

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

open scoped Topology
namespace ClassFieldTower.ProP
open ProCGroups
noncomputable section
universe u
variable {p : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
def nextClosedAugmentationLayerIn (n : ℕ) :
    Submodule (ModPCompletedGroupAlgebra p sourceData.carrier)
      (closedAugmentationPower p sourceData.carrier n)
ClassFieldTower.ProP.AugmentationInitialFormSpace

The degree-n associated-graded augmentation piece Iⁿ/Iⁿ⁺¹.

Source context 7 commands

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

open scoped Topology
namespace ClassFieldTower.ProP
open ProCGroups
noncomputable section
universe u
variable {p : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
abbrev AugmentationInitialFormSpace (n : ℕ)
ClassFieldTower.ProP.zassenhausInitialFormAt

The degree-n initial form of an element with a depth-n witness.

Source context 7 commands

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

open scoped Topology
namespace ClassFieldTower.ProP
open ProCGroups
noncomputable section
universe u
variable {p : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
def zassenhausInitialFormAt
    (n : ℕ) (g : sourceData.carrier)
    (hg : ZassenhausDepthAtLeast p n g) :
    AugmentationInitialFormSpace (p := p) (sourceData := sourceData) n
ClassFieldTower.ProP.zassenhausInitialFormAt_eq_zero_iff

The initial form vanishes exactly when the element lies one layer deeper.

Source context 7 commands

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

open scoped Topology
namespace ClassFieldTower.ProP
open ProCGroups
noncomputable section
universe u
variable {p : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
theorem zassenhausInitialFormAt_eq_zero_iff
    (n : ℕ) (g : sourceData.carrier)
    (hg : ZassenhausDepthAtLeast p n g) :
    zassenhausInitialFormAt (sourceData := sourceData) n g hg = 0 ↔
      ZassenhausDepthAtLeast p (n + 1) g
ClassFieldTower.ProP.FiniteProPPresentation.relatorInitialFormAt

Initial form of one displayed relator.

Source context 11 commands

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

open scoped Topology
namespace ClassFieldTower.ProP
open ProCGroups
noncomputable section
universe u
variable {p : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
namespace FiniteProPPresentation
variable {d r : ℕ}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
def relatorInitialFormAt
    (P : FiniteProPPresentation p d r sourceData G)
    (n : ℕ) (i : Fin r) (hi : P.RelatorZassenhausDepthAtLeast n i) :
    AugmentationInitialFormSpace (p := p) (sourceData := sourceData) n
ClassFieldTower.ProP.FiniteProPPresentation.relatorInitialFormFamilyAt

The displayed relation family in one associated-graded degree.

Source context 11 commands

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

open scoped Topology
namespace ClassFieldTower.ProP
open ProCGroups
noncomputable section
universe u
variable {p : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
namespace FiniteProPPresentation
variable {d r : ℕ}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
def relatorInitialFormFamilyAt
    (P : FiniteProPPresentation p d r sourceData G)
    (n : ℕ) (hrel : ∀ i, P.RelatorZassenhausDepthAtLeast n i) :
    Fin r → AugmentationInitialFormSpace (p := p) (sourceData := sourceData) n
ClassFieldTower.ProP.FiniteProPPresentation.minimalRelatorInitialFormFamily

Minimality canonically produces the degree-two initial-form family.

Source context 11 commands

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

open scoped Topology
namespace ClassFieldTower.ProP
open ProCGroups
noncomputable section
universe u
variable {p : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
namespace FiniteProPPresentation
variable {d r : ℕ}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
def minimalRelatorInitialFormFamily
    (P : FiniteProPPresentation p d r sourceData G) (hP : P.IsMinimal) :
    Fin r → AugmentationInitialFormSpace (p := p) (sourceData := sourceData) 2