Rejig subgroups, add ideals (#79)

This commit is contained in:
Patrick Stevens
2019-11-19 19:56:01 +00:00
committed by GitHub
parent f0790e4f52
commit f2f4e867fc
8 changed files with 69 additions and 145 deletions

View File

@@ -20,11 +20,11 @@ module Groups.Abelian.Lemmas where
directSumAbelianGroup : {m n o p : _} {A : Set m} {S : Setoid {m} {o} A} {_·A_ : A A A} {B : Set n} {T : Setoid {n} {p} B} {_·B_ : B B B} {underG : Group S _·A_} {underH : Group T _·B_} (G : AbelianGroup underG) (h : AbelianGroup underH) (AbelianGroup (directSumGroup underG underH))
AbelianGroup.commutative (directSumAbelianGroup {A = A} {B} G H) = AbelianGroup.commutative G ,, AbelianGroup.commutative H
subgroupOfAbelianIsAbelian : {a b c d : _} {A : Set a} {B : Set b} {S : Setoid {a} {c} A} {T : Setoid {b} {d} B} {_+A_ : A A A} {_+B_ : B B B} {G : Group S _+A_} {H : Group T _+B_} {f : B A} {fHom : GroupHom H G f} Subgroup G H fHom AbelianGroup G AbelianGroup H
AbelianGroup.commutative (subgroupOfAbelianIsAbelian {S = S} {_+B_ = _+B_} {fHom = fHom} record { fInj = fInj } record { commutative = commutative }) {x} {y} = SetoidInjection.injective fInj (transitive (GroupHom.groupHom fHom) (transitive commutative (symmetric (GroupHom.groupHom fHom))))
subgroupOfAbelianIsAbelian : {a b c d : _} {A : Set a} {B : Set b} {S : Setoid {a} {c} A} {T : Setoid {b} {d} B} {_+A_ : A A A} {_+B_ : B B B} {G : Group S _+A_} {H : Group T _+B_} {f : B A} {fHom : GroupHom H G f} SetoidInjection T S f AbelianGroup G AbelianGroup H
AbelianGroup.commutative (subgroupOfAbelianIsAbelian {S = S} {_+B_ = _+B_} {fHom = fHom} fInj record { commutative = commutative }) {x} {y} = SetoidInjection.injective fInj (transitive (GroupHom.groupHom fHom) (transitive commutative (symmetric (GroupHom.groupHom fHom))))
where
open Setoid S
open Equivalence eq
abelianIsGroupProperty : {a b c d : _} {A : Set a} {B : Set b} {S : Setoid {a} {c} A} {T : Setoid {b} {d} B} {_+A_ : A A A} {_+B_ : B B B} {G : Group S _+A_} {H : Group T _+B_} GroupsIsomorphic G H AbelianGroup H AbelianGroup G
abelianIsGroupProperty iso abH = subgroupOfAbelianIsAbelian {fHom = GroupIso.groupHom (GroupsIsomorphic.proof iso)} (record { fInj = SetoidBijection.inj (GroupIso.bij (GroupsIsomorphic.proof iso)) }) abH
abelianIsGroupProperty iso abH = subgroupOfAbelianIsAbelian {fHom = GroupIso.groupHom (GroupsIsomorphic.proof iso)} (SetoidBijection.inj (GroupIso.bij (GroupsIsomorphic.proof iso))) abH