@@ -19,26 +19,26 @@ variables (C : Type u₁) [category.{v₁} C] [monoidal_category.{v₁} C]
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variables {C}
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/-- A module object for a monoid object, all internal to some monoidal category. -/
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- structure Mod (A : Mon_ C) :=
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+ structure Mod_ (A : Mon_ C) :=
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(X : C)
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(act : A.X ⊗ X ⟶ X)
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(one_act' : (A.one ⊗ 𝟙 X) ≫ act = (λ_ X).hom . obviously)
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(assoc' : (A.mul ⊗ 𝟙 X) ≫ act = (α_ A.X A.X X).hom ≫ (𝟙 A.X ⊗ act) ≫ act . obviously)
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- restate_axiom Mod .one_act'
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- restate_axiom Mod .assoc'
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- attribute [simp, reassoc] Mod .one_act Mod .assoc
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+ restate_axiom Mod_ .one_act'
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+ restate_axiom Mod_ .assoc'
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+ attribute [simp, reassoc] Mod_ .one_act Mod_ .assoc
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- namespace Mod
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+ namespace Mod_
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- variables {A : Mon_ C} (M : Mod A)
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+ variables {A : Mon_ C} (M : Mod_ A)
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lemma assoc_flip : (𝟙 A.X ⊗ M.act) ≫ M.act = (α_ A.X A.X M.X).inv ≫ (A.mul ⊗ 𝟙 M.X) ≫ M.act :=
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by simp
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/-- A morphism of module objects. -/
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@[ext]
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- structure hom (M N : Mod A) :=
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+ structure hom (M N : Mod_ A) :=
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(hom : M.X ⟶ N.X)
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(act_hom' : M.act ≫ hom = (𝟙 A.X ⊗ hom) ≫ N.act . obviously)
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@@ -47,37 +47,37 @@ attribute [simp, reassoc] hom.act_hom
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/-- The identity morphism on a module object. -/
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@[simps]
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- def id (M : Mod A) : hom M M :=
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+ def id (M : Mod_ A) : hom M M :=
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{ hom := 𝟙 M.X, }
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- instance hom_inhabited (M : Mod A) : inhabited (hom M M) := ⟨id M⟩
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+ instance hom_inhabited (M : Mod_ A) : inhabited (hom M M) := ⟨id M⟩
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/-- Composition of module object morphisms. -/
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@[simps]
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- def comp {M N O : Mod A} (f : hom M N) (g : hom N O) : hom M O :=
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+ def comp {M N O : Mod_ A} (f : hom M N) (g : hom N O) : hom M O :=
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{ hom := f.hom ≫ g.hom, }
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- instance : category (Mod A) :=
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+ instance : category (Mod_ A) :=
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{ hom := λ M N, hom M N,
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id := id,
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comp := λ M N O f g, comp f g, }
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- @[simp] lemma id_hom' (M : Mod A) : (𝟙 M : hom M M).hom = 𝟙 M.X := rfl
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- @[simp] lemma comp_hom' {M N K : Mod A} (f : M ⟶ N) (g : N ⟶ K) :
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+ @[simp] lemma id_hom' (M : Mod_ A) : (𝟙 M : hom M M).hom = 𝟙 M.X := rfl
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+ @[simp] lemma comp_hom' {M N K : Mod_ A} (f : M ⟶ N) (g : N ⟶ K) :
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(f ≫ g : hom M K).hom = f.hom ≫ g.hom := rfl
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variables (A)
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/-- A monoid object as a module over itself. -/
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@[simps]
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- def regular : Mod A :=
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+ def regular : Mod_ A :=
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{ X := A.X,
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act := A.mul, }
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- instance : inhabited (Mod A) := ⟨regular A⟩
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+ instance : inhabited (Mod_ A) := ⟨regular A⟩
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/-- The forgetful functor from module objects to the ambient category. -/
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- def forget : Mod A ⥤ C :=
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+ def forget : Mod_ A ⥤ C :=
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{ obj := λ A, A.X,
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map := λ A B f, f.hom, }
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@@ -88,7 +88,7 @@ A morphism of monoid objects induces a "restriction" or "comap" functor
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between the categories of module objects.
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-/
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@[simps]
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- def comap {A B : Mon_ C} (f : A ⟶ B) : Mod B ⥤ Mod A :=
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+ def comap {A B : Mon_ C} (f : A ⟶ B) : Mod_ B ⥤ Mod_ A :=
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{ obj := λ M,
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{ X := M.X,
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act := (f.hom ⊗ 𝟙 M.X) ≫ M.act,
@@ -102,7 +102,7 @@ def comap {A B : Mon_ C} (f : A ⟶ B) : Mod B ⥤ Mod A :=
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-- oh, for homotopy.io in a widget!
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slice_rhs 2 3 { rw [id_tensor_comp_tensor_id, ←tensor_id_comp_id_tensor], },
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rw id_tensor_comp,
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- slice_rhs 4 5 { rw Mod .assoc_flip, },
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+ slice_rhs 4 5 { rw Mod_ .assoc_flip, },
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slice_rhs 3 4 { rw associator_inv_naturality, },
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slice_rhs 2 3 { rw [←tensor_id, associator_inv_naturality], },
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slice_rhs 1 3 { rw [iso.hom_inv_id_assoc], },
@@ -123,4 +123,4 @@ def comap {A B : Mon_ C} (f : A ⟶ B) : Mod B ⥤ Mod A :=
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-- Lots more could be said about `comap`, e.g. how it interacts with
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-- identities, compositions, and equalities of monoid object morphisms.
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- end Mod
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+ end Mod_
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