ProCGroups.CrowellExactSequence.Profinite.SequenceMaps.Basic
This file defines the completed differential boundary and the maps from completed and separated differential modules to the completed \(\mathbb Z_C\)-group algebra. It proves their values on universal differentials and compatibility with separation.
def presentedCompletedDifferentialBoundaryProCInteger
(C : ProCGroups.FiniteGroupClass.{u}) (psi : ContinuousMonoidHom G H) (g : G) :
ZCCompletedGroupAlgebra C H :=
zcCompletedGroupAlgebraBoundary C psi.toMonoidHom gThe displayed boundary map \(A_{\psi}(C) \to \mathbb{Z}_C\llbracket H\rrbracket\) sends the generator \(dg\) to \(\psi(g)-1\).
def presentedCompletedDifferentialToCompletedGroupAlgebraProCInteger
(C : ProCGroups.FiniteGroupClass.{u}) (psi : ContinuousMonoidHom G H) :
ZCCompletedDifferentialModule C psi.toMonoidHom →ₗ[ZCCompletedGroupAlgebra C H]
ZCCompletedGroupAlgebra C H :=
zcToCompletedGroupAlgebra C psi.toMonoidHomThe displayed Crowell map \(A_{\psi}(C) \to \mathbb{Z}_C\llbracket H\rrbracket\).
def presentedSeparatedDifferentialToCompletedGroupAlgebraProCInteger
(C : ProCGroups.FiniteGroupClass.{u})
(hC : ProCGroups.FiniteGroupClass.Hereditary C)
(psi : ContinuousMonoidHom G H) :
ZCSeparatedCompletedDifferentialModule C psi.toMonoidHom →ₗ[ZCCompletedGroupAlgebra C H]
ZCCompletedGroupAlgebra C H :=
zcSeparatedCompletedDifferentialModuleToCompletedGroupAlgebra C hC psiThe displayed Crowell boundary \(A_{\psi}(C)_{\mathrm{sep}} \to \mathbb{Z}_C\llbracket H\rrbracket\) from the separated completed middle term.
omit [IsTopologicalGroup G] in
@[simp]
theorem presentedCompletedDifferentialToCompletedGroupAlgebraProCInteger_d
(C : ProCGroups.FiniteGroupClass.{u}) (psi : ContinuousMonoidHom G H) (g : G) :
presentedCompletedDifferentialToCompletedGroupAlgebraProCInteger (G := G) (H := H) C psi
(zcUniversalDifferential C psi.toMonoidHom g) =
presentedCompletedDifferentialBoundaryProCInteger (G := G) (H := H) C psi gThe displayed Crowell map sends the universal differential \(dg\) to \(\psi(g)-1\).
Show Lean proof
by
exact zcToCompletedGroupAlgebra_universal C psi.toMonoidHom g
omit [IsTopologicalGroup G] in
@[simp]
theorem presentedSeparatedDifferentialToCompletedGroupAlgebraProCInteger_d
(C : ProCGroups.FiniteGroupClass.{u})
(hC : ProCGroups.FiniteGroupClass.Hereditary C)
(psi : ContinuousMonoidHom G H) (g : G) :
presentedSeparatedDifferentialToCompletedGroupAlgebraProCInteger
(G := G) (H := H) C hC psi
(zcSeparatedUniversalDifferential C psi.toMonoidHom g) =
presentedCompletedDifferentialBoundaryProCInteger (G := G) (H := H) C psi gThe separated Crowell boundary sends the separated universal differential \(dg\) to \(\psi(g)-1\).
Show Lean proof
by
exact zcSeparatedCompletedDifferentialModuleToCompletedGroupAlgebra_universal
(G := G) (H := H) C hC psi g
omit [IsTopologicalGroup G] in
theorem presentedSepToZC_comp_toSep
(C : ProCGroups.FiniteGroupClass.{u})
(hC : ProCGroups.FiniteGroupClass.Hereditary C)
(psi : ContinuousMonoidHom G H) :
(presentedSeparatedDifferentialToCompletedGroupAlgebraProCInteger
(G := G) (H := H) C hC psi).comp
(zcCompletedDifferentialModuleToSeparated C psi.toMonoidHom) =
presentedCompletedDifferentialToCompletedGroupAlgebraProCInteger
(G := G) (H := H) C psiPassing the completed differential module to its separated quotient before applying the separated Crowell map recovers the completed Crowell map.
Show Lean proof
by
exact zcSeparatedCompletedDifferentialModuleToCompletedGroupAlgebra_comp_toSeparated
(G := G) (H := H) C hC psi