The category of commutative groups in a Cartesian monoidal category

structure CategoryTheory.CommGrp (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : Type (max u₁ v₁)

A commutative group object internal to a Cartesian monoidal category.

• X : C

  The underlying object in the ambient monoidal category

• grp : GrpObj self.X
• comm : IsCommMonObj self.X

@[deprecated CategoryTheory.CommGrp (since := "2025-10-13")]

def CategoryTheory.CommGrp_ (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : Type (max u₁ v₁)

Alias of CategoryTheory.CommGrp.

---

A commutative group object internal to a Cartesian monoidal category.

@[reducible, inline]

abbrev CategoryTheory.CommGrp.toGrp {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] (A : CommGrp C) : Grp C

A commutative group object is a group object.

theorem CategoryTheory.CommGrp.toGrp_X {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] (A : CommGrp C) : A.toGrp.X = A.X

@[deprecated CategoryTheory.CommGrp.toGrp (since := "2025-10-13")]

def CategoryTheory.CommGrp.toGrp_ {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] (A : CommGrp C) : Grp C

Alias of CategoryTheory.CommGrp.toGrp.

---

A commutative group object is a group object.

def CategoryTheory.CommGrp.toCommMon {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] (A : CommGrp C) : CommMon C

A commutative group object is a commutative monoid object.

@[simp]

theorem CategoryTheory.CommGrp.toCommMon_X {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] (A : CommGrp C) : A.toCommMon.X = A.X

@[deprecated CategoryTheory.CommGrp.toCommMon (since := "2025-09-15")]

def CategoryTheory.CommGrp.toCommMon_ {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] (A : CommGrp C) : CommMon C

Alias of CategoryTheory.CommGrp.toCommMon.

---

A commutative group object is a commutative monoid object.

@[reducible, inline]

abbrev CategoryTheory.CommGrp.toMon {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] (A : CommGrp C) : Mon C

A commutative group object is a monoid object.

@[deprecated CategoryTheory.CommGrp.toMon (since := "2025-09-15")]

def CategoryTheory.CommGrp.toMon_ {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] (A : CommGrp C) : Mon C

Alias of CategoryTheory.CommGrp.toMon.

---

A commutative group object is a monoid object.

def CategoryTheory.CommGrp.trivial (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : CommGrp C

The trivial commutative group object.

@[simp]

theorem CategoryTheory.CommGrp.trivial_grp_mul (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : MonObj.mul = (MonoidalCategoryStruct.leftUnitor (MonoidalCategoryStruct.tensorUnit C)).hom

@[simp]

theorem CategoryTheory.CommGrp.trivial_grp_one (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : MonObj.one = CategoryStruct.id (MonoidalCategoryStruct.tensorUnit C)

@[simp]

theorem CategoryTheory.CommGrp.trivial_grp_inv (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : GrpObj.inv = CategoryStruct.id (MonoidalCategoryStruct.tensorUnit C)

@[simp]

theorem CategoryTheory.CommGrp.trivial_X (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : (trivial C).X = MonoidalCategoryStruct.tensorUnit C

instance CategoryTheory.CommGrp.instInhabited {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : Inhabited (CommGrp C)

instance CategoryTheory.CommGrp.instCategory {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : Category.{v₁, max u₁ v₁} (CommGrp C)

@[simp]

theorem CategoryTheory.CommGrp.id_hom {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] (A : CommGrp C) : (CategoryStruct.id A).hom = CategoryStruct.id A.toGrp

@[simp]

theorem CategoryTheory.CommGrp.comp_hom {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {R S T : CommGrp C} (f : R ⟶ S) (g : S ⟶ T) : (CategoryStruct.comp f g).hom = CategoryStruct.comp f.hom g.hom

theorem CategoryTheory.CommGrp.hom_ext {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {A B : CommGrp C} (f g : A ⟶ B) (h : f.hom.hom.hom = g.hom.hom.hom) : f = g

theorem CategoryTheory.CommGrp.hom_ext_iff {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {A B : CommGrp C} {f g : A ⟶ B} : f = g ↔ f.hom.hom.hom = g.hom.hom.hom

@[deprecated CategoryTheory.CommGrp.id_hom (since := "2025-12-18")]

theorem CategoryTheory.CommGrp.id' {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] (A : CommGrp C) : (CategoryStruct.id A).hom = CategoryStruct.id A.toGrp

Alias of CategoryTheory.CommGrp.id_hom.

@[deprecated CategoryTheory.CommGrp.comp_hom (since := "2025-12-18")]

theorem CategoryTheory.CommGrp.comp' {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {R S T : CommGrp C} (f : R ⟶ S) (g : S ⟶ T) : (CategoryStruct.comp f g).hom = CategoryStruct.comp f.hom g.hom

Alias of CategoryTheory.CommGrp.comp_hom.

def CategoryTheory.CommGrp.forget₂Grp (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : Functor (CommGrp C) (Grp C)

The forgetful functor from commutative group objects to group objects.

@[simp]

theorem CategoryTheory.CommGrp.forget₂Grp_obj_X (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] (A : CommGrp C) : ((forget₂Grp C).obj A).X = A.X

@[deprecated CategoryTheory.CommGrp.forget₂Grp (since := "2025-10-13")]

def CategoryTheory.CommGrp.forget₂Grp_ (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : Functor (CommGrp C) (Grp C)

Alias of CategoryTheory.CommGrp.forget₂Grp.

---

The forgetful functor from commutative group objects to group objects.

def CategoryTheory.CommGrp.fullyFaithfulForget₂Grp (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : (forget₂Grp C).FullyFaithful

The forgetful functor from commutative group objects to group objects is fully faithful.

@[deprecated CategoryTheory.CommGrp.fullyFaithfulForget₂Grp (since := "2025-10-13")]

def CategoryTheory.CommGrp.fullyFaithfulForget₂Grp_ (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : (forget₂Grp C).FullyFaithful

Alias of CategoryTheory.CommGrp.fullyFaithfulForget₂Grp.

---

The forgetful functor from commutative group objects to group objects is fully faithful.

instance CategoryTheory.CommGrp.instFullGrpForget₂Grp (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : (forget₂Grp C).Full

instance CategoryTheory.CommGrp.instFaithfulGrpForget₂Grp (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : (forget₂Grp C).Faithful

@[simp]

theorem CategoryTheory.CommGrp.forget₂Grp_obj_one (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] (A : CommGrp C) : MonObj.one = MonObj.one

@[simp]

theorem CategoryTheory.CommGrp.forget₂Grp_obj_mul (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] (A : CommGrp C) : MonObj.mul = MonObj.mul

@[simp]

theorem CategoryTheory.CommGrp.forget₂Grp_map_hom (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {A B : CommGrp C} (f : A ⟶ B) : ((forget₂Grp C).map f).hom = f.hom.hom

def CategoryTheory.CommGrp.forget₂CommMon (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : Functor (CommGrp C) (CommMon C)

The forgetful functor from commutative group objects to commutative monoid objects.

@[deprecated CategoryTheory.CommGrp.forget₂CommMon (since := "2025-09-15")]

def CategoryTheory.CommGrp.forget₂CommMon_ (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : Functor (CommGrp C) (CommMon C)

Alias of CategoryTheory.CommGrp.forget₂CommMon.

---

The forgetful functor from commutative group objects to commutative monoid objects.

def CategoryTheory.CommGrp.fullyFaithfulForget₂CommMon (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : (forget₂CommMon C).FullyFaithful

The forgetful functor from commutative group objects to commutative monoid objects is fully faithful.

instance CategoryTheory.CommGrp.instFullCommMonForget₂CommMon (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : (forget₂CommMon C).Full

instance CategoryTheory.CommGrp.instFaithfulCommMonForget₂CommMon (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : (forget₂CommMon C).Faithful

@[simp]

theorem CategoryTheory.CommGrp.forget₂CommMon_obj_one (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] (A : CommGrp C) : MonObj.one = MonObj.one

@[simp]

theorem CategoryTheory.CommGrp.forget₂CommMon_obj_mul (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] (A : CommGrp C) : MonObj.mul = MonObj.mul

@[simp]

theorem CategoryTheory.CommGrp.forget₂CommMon_map_hom (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {A B : CommGrp C} (f : A ⟶ B) : ((forget₂CommMon C).map f).hom = f.hom.hom

def CategoryTheory.CommGrp.forget (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : Functor (CommGrp C) C

The forgetful functor from commutative group objects to the ambient category.

@[simp]

theorem CategoryTheory.CommGrp.forget_obj (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] (X : CommGrp C) : (forget C).obj X = X.X

@[simp]

theorem CategoryTheory.CommGrp.forget_map (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {X✝ Y✝ : CommGrp C} (f : X✝ ⟶ Y✝) : (forget C).map f = f.hom.hom.hom

instance CategoryTheory.CommGrp.instFaithfulForget (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : (forget C).Faithful

@[simp]

theorem CategoryTheory.CommGrp.forget₂Grp_comp_forget (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : (forget₂Grp C).comp (Grp.forget C) = forget C

@[simp]

theorem CategoryTheory.CommGrp.forget₂CommMon_comp_forget (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : (forget₂CommMon C).comp (CommMon.forget C) = forget C

instance CategoryTheory.CommGrp.instIsIsoGrpHom (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {G H : CommGrp C} {f : G ⟶ H} [IsIso f] : IsIso f.hom

instance CategoryTheory.CommGrp.instIsIsoMonHomGrp (C : Type u₁) [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {G H : CommGrp C} {f : G ⟶ H} [IsIso f] : IsIso f.hom.hom

def CategoryTheory.CommGrp.mkIso' {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {G H : C} (e : G ≅ H) [GrpObj G] [IsCommMonObj G] [GrpObj H] [IsCommMonObj H] [IsMonHom e.hom] : { X := G, grp := inst✝, comm := inst✝¹ } ≅ { X := H, grp := inst✝², comm := inst✝³ }

Construct an isomorphism of commutative group objects by giving a monoid isomorphism between the underlying objects.

@[simp]

theorem CategoryTheory.CommGrp.mkIso'_inv_hom_hom_hom {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {G H : C} (e : G ≅ H) [GrpObj G] [IsCommMonObj G] [GrpObj H] [IsCommMonObj H] [IsMonHom e.hom] : (mkIso' e).inv.hom.hom.hom = e.inv

@[simp]

theorem CategoryTheory.CommGrp.mkIso'_hom_hom_hom_hom {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {G H : C} (e : G ≅ H) [GrpObj G] [IsCommMonObj G] [GrpObj H] [IsCommMonObj H] [IsMonHom e.hom] : (mkIso' e).hom.hom.hom.hom = e.hom

@[reducible, inline]

abbrev CategoryTheory.CommGrp.mkIso {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {G H : CommGrp C} (e : G.X ≅ H.X) (one_f : CategoryStruct.comp MonObj.one e.hom = MonObj.one := by cat_disch) (mul_f : CategoryStruct.comp MonObj.mul e.hom = CategoryStruct.comp (MonoidalCategoryStruct.tensorHom e.hom e.hom) MonObj.mul := by cat_disch) : G ≅ H

Construct an isomorphism of group objects by giving an isomorphism between the underlying objects and checking compatibility with unit and multiplication only in the forward direction.

@[simp]

theorem CategoryTheory.CommGrp.mkIso_hom_hom_hom_hom {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {G H : CommGrp C} (e : G.X ≅ H.X) (one_f : CategoryStruct.comp MonObj.one e.hom = MonObj.one := by cat_disch) (mul_f : CategoryStruct.comp MonObj.mul e.hom = CategoryStruct.comp (MonoidalCategoryStruct.tensorHom e.hom e.hom) MonObj.mul := by cat_disch) : (mkIso e one_f mul_f).hom.hom.hom.hom = e.hom

@[simp]

theorem CategoryTheory.CommGrp.mkIso_inv_hom_hom_hom {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {G H : CommGrp C} (e : G.X ≅ H.X) (one_f : CategoryStruct.comp MonObj.one e.hom = MonObj.one := by cat_disch) (mul_f : CategoryStruct.comp MonObj.mul e.hom = CategoryStruct.comp (MonoidalCategoryStruct.tensorHom e.hom e.hom) MonObj.mul := by cat_disch) : (mkIso e one_f mul_f).inv.hom.hom.hom = e.inv

@[deprecated CategoryTheory.CommGrp.mkIso_hom_hom_hom_hom (since := "2025-12-18")]

theorem CategoryTheory.CommGrp.mkIso_hom_hom {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {G H : CommGrp C} (e : G.X ≅ H.X) (one_f : CategoryStruct.comp MonObj.one e.hom = MonObj.one := by cat_disch) (mul_f : CategoryStruct.comp MonObj.mul e.hom = CategoryStruct.comp (MonoidalCategoryStruct.tensorHom e.hom e.hom) MonObj.mul := by cat_disch) : (mkIso e one_f mul_f).hom.hom.hom.hom = e.hom

Alias of CategoryTheory.CommGrp.mkIso_hom_hom_hom_hom.

@[deprecated CategoryTheory.CommGrp.mkIso_inv_hom_hom_hom (since := "2025-12-18")]

theorem CategoryTheory.CommGrp.mkIso_inv_hom {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {G H : CommGrp C} (e : G.X ≅ H.X) (one_f : CategoryStruct.comp MonObj.one e.hom = MonObj.one := by cat_disch) (mul_f : CategoryStruct.comp MonObj.mul e.hom = CategoryStruct.comp (MonoidalCategoryStruct.tensorHom e.hom e.hom) MonObj.mul := by cat_disch) : (mkIso e one_f mul_f).inv.hom.hom.hom = e.inv

Alias of CategoryTheory.CommGrp.mkIso_inv_hom_hom_hom.

instance CategoryTheory.CommGrp.uniqueHomFromTrivial {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] (A : CommGrp C) : Unique (trivial C ⟶ A)

instance CategoryTheory.CommGrp.instHasInitial {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : Limits.HasInitial (CommGrp C)

def CategoryTheory.Functor.mapCommGrp {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] (F : Functor C D) [F.Braided] : Functor (CommGrp C) (CommGrp D)

A finite-product-preserving functor takes commutative group objects to commutative group objects.

@[simp]

theorem CategoryTheory.Functor.mapCommGrp_map_hom_hom_hom {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] (F : Functor C D) [F.Braided] {X✝ Y✝ : CommGrp C} (f : X✝ ⟶ Y✝) : (F.mapCommGrp.map f).hom.hom.hom = F.map f.hom.hom.hom

@[simp]

theorem CategoryTheory.Functor.mapCommGrp_obj_grp_inv {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] (F : Functor C D) [F.Braided] (A : CommGrp C) : GrpObj.inv = F.map GrpObj.inv

@[simp]

theorem CategoryTheory.Functor.mapCommGrp_obj_grp_mul {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] (F : Functor C D) [F.Braided] (A : CommGrp C) : MonObj.mul = CategoryStruct.comp (LaxMonoidal.μ F A.X A.X) (F.map MonObj.mul)

@[simp]

theorem CategoryTheory.Functor.mapCommGrp_obj_grp_one {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] (F : Functor C D) [F.Braided] (A : CommGrp C) : MonObj.one = CategoryStruct.comp (LaxMonoidal.ε F) (F.map MonObj.one)

@[simp]

theorem CategoryTheory.Functor.mapCommGrp_obj_X {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] (F : Functor C D) [F.Braided] (A : CommGrp C) : (F.mapCommGrp.obj A).X = F.obj A.X

instance CategoryTheory.Functor.Faithful.mapCommGrp {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] {F : Functor C D} [F.Braided] [F.Faithful] : F.mapCommGrp.Faithful

def CategoryTheory.Functor.FullyFaithful.mapCommGrp {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] {F : Functor C D} [F.Braided] (hF : F.FullyFaithful) : F.mapCommGrp.FullyFaithful

If F : C ⥤ D is a fully faithful monoidal functor, then CommGrpCat(F) : CommGrpCat C ⥤ CommGrpCat D is fully faithful too.

@[simp]

theorem CategoryTheory.Functor.FullyFaithful.mapCommGrp_preimage {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] {F : Functor C D} [F.Braided] (hF : F.FullyFaithful) {X✝ Y✝ : CommGrp C} (f : F.mapCommGrp.obj X✝ ⟶ F.mapCommGrp.obj Y✝) : hF.mapCommGrp.preimage f = InducedCategory.homMk (Grp.homMk' (hF.mapMon.preimage f.hom.hom))

instance CategoryTheory.Functor.Full.mapCommGrp {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] {F : Functor C D} [F.Braided] [F.Full] [F.Faithful] : F.mapCommGrp.Full

@[simp]

theorem CategoryTheory.Functor.mapCommGrp_id_one {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] (A : CommGrp C) : MonObj.one = CategoryStruct.comp (CategoryStruct.id (MonoidalCategoryStruct.tensorUnit C)) MonObj.one

@[simp]

theorem CategoryTheory.Functor.mapCommpGrp_id_mul {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] (A : CommGrp C) : MonObj.mul = CategoryStruct.comp (CategoryStruct.id (MonoidalCategoryStruct.tensorObj A.X A.X)) MonObj.mul

@[simp]

theorem CategoryTheory.Functor.comp_mapCommGrp_one {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] {E : Type u₃} [Category.{v₃, u₃} E] [CartesianMonoidalCategory E] [BraidedCategory E] {F : Functor C D} [F.Braided] {G : Functor D E} [G.Braided] (A : CommGrp C) : MonObj.one = CategoryStruct.comp (LaxMonoidal.ε (F.comp G)) ((F.comp G).map MonObj.one)

@[simp]

theorem CategoryTheory.Functor.comp_mapCommGrp_mul {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] {E : Type u₃} [Category.{v₃, u₃} E] [CartesianMonoidalCategory E] [BraidedCategory E] {F : Functor C D} [F.Braided] {G : Functor D E} [G.Braided] (A : CommGrp C) : MonObj.mul = CategoryStruct.comp (LaxMonoidal.μ (F.comp G) A.X A.X) ((F.comp G).map MonObj.mul)

def CategoryTheory.Functor.mapCommGrpIdIso {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] : (Functor.id C).mapCommGrp ≅ Functor.id (CommGrp C)

The identity functor is also the identity on commutative group objects.

@[simp]

theorem CategoryTheory.Functor.mapCommGrpIdIso_hom_app_hom_hom_hom {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] (X : CommGrp C) : (mapCommGrpIdIso.hom.app X).hom.hom.hom = CategoryStruct.id X.X

@[simp]

theorem CategoryTheory.Functor.mapCommGrpIdIso_inv_app_hom_hom_hom {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] (X : CommGrp C) : (mapCommGrpIdIso.inv.app X).hom.hom.hom = CategoryStruct.id X.X

def CategoryTheory.Functor.mapCommGrpCompIso {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] {E : Type u₃} [Category.{v₃, u₃} E] [CartesianMonoidalCategory E] [BraidedCategory E] {F : Functor C D} [F.Braided] {G : Functor D E} [G.Braided] : (F.comp G).mapCommGrp ≅ F.mapCommGrp.comp G.mapCommGrp

The composition functor is also the composition on commutative group objects.

@[simp]

theorem CategoryTheory.Functor.mapCommGrpCompIso_hom_app_hom_hom_hom {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] {E : Type u₃} [Category.{v₃, u₃} E] [CartesianMonoidalCategory E] [BraidedCategory E] {F : Functor C D} [F.Braided] {G : Functor D E} [G.Braided] (X : CommGrp C) : (mapCommGrpCompIso.hom.app X).hom.hom.hom = CategoryStruct.id (G.obj (F.obj X.X))

@[simp]

theorem CategoryTheory.Functor.mapCommGrpCompIso_inv_app_hom_hom_hom {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] {E : Type u₃} [Category.{v₃, u₃} E] [CartesianMonoidalCategory E] [BraidedCategory E] {F : Functor C D} [F.Braided] {G : Functor D E} [G.Braided] (X : CommGrp C) : (mapCommGrpCompIso.inv.app X).hom.hom.hom = CategoryStruct.id (G.obj (F.obj X.X))

def CategoryTheory.Functor.mapCommGrpNatTrans {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] {F F' : Functor C D} [F.Braided] [F'.Braided] (f : F ⟶ F') : F.mapCommGrp ⟶ F'.mapCommGrp

Natural transformations between functors lift to commutative group objects.

@[simp]

theorem CategoryTheory.Functor.mapCommGrpNatTrans_app_hom_hom_hom {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] {F F' : Functor C D} [F.Braided] [F'.Braided] (f : F ⟶ F') (X : CommGrp C) : ((mapCommGrpNatTrans f).app X).hom.hom.hom = f.app X.X

def CategoryTheory.Functor.mapCommGrpNatIso {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] {F F' : Functor C D} [F.Braided] [F'.Braided] (e : F ≅ F') : F.mapCommGrp ≅ F'.mapCommGrp

Natural isomorphisms between functors lift to commutative group objects.

@[simp]

theorem CategoryTheory.Functor.mapCommGrpNatIso_hom_app_hom_hom_hom {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] {F F' : Functor C D} [F.Braided] [F'.Braided] (e : F ≅ F') (X : CommGrp C) : ((mapCommGrpNatIso e).hom.app X).hom.hom.hom = e.hom.app X.X

@[simp]

theorem CategoryTheory.Functor.mapCommGrpNatIso_inv_app_hom_hom_hom {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] {F F' : Functor C D} [F.Braided] [F'.Braided] (e : F ≅ F') (X : CommGrp C) : ((mapCommGrpNatIso e).inv.app X).hom.hom.hom = e.inv.app X.X

noncomputable def CategoryTheory.Functor.mapCommGrpFunctor {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] : Functor (C ⥤ₗ D) (Functor (CommGrp C) (CommGrp D))

mapCommGrp is functorial in the left-exact functor.

@[simp]

theorem CategoryTheory.Functor.mapCommGrpFunctor_map {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] {X✝ Y✝ : C ⥤ₗ D} (α : X✝ ⟶ Y✝) : mapCommGrpFunctor.map α = mapCommGrpNatTrans α.hom

@[simp]

theorem CategoryTheory.Functor.mapCommGrpFunctor_obj {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] (F : C ⥤ₗ D) : mapCommGrpFunctor.obj F = F.obj.mapCommGrp

noncomputable def CategoryTheory.Adjunction.mapCommGrp {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] {F : Functor C D} {G : Functor D C} (a : F ⊣ G) [F.Braided] [G.Braided] : F.mapCommGrp ⊣ G.mapCommGrp

An adjunction of braided functors lifts to an adjunction of their lifts to commutative group objects.

@[simp]

theorem CategoryTheory.Adjunction.mapCommGrp_unit {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] {F : Functor C D} {G : Functor D C} (a : F ⊣ G) [F.Braided] [G.Braided] : a.mapCommGrp.unit = CategoryStruct.comp Functor.mapCommGrpIdIso.inv (CategoryStruct.comp (Functor.mapCommGrpNatTrans a.unit) Functor.mapCommGrpCompIso.hom)

@[simp]

theorem CategoryTheory.Adjunction.mapCommGrp_counit {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] {F : Functor C D} {G : Functor D C} (a : F ⊣ G) [F.Braided] [G.Braided] : a.mapCommGrp.counit = CategoryStruct.comp Functor.mapCommGrpCompIso.inv (CategoryStruct.comp (Functor.mapCommGrpNatTrans a.counit) Functor.mapCommGrpIdIso.hom)

noncomputable def CategoryTheory.Equivalence.mapCommGrp {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] (e : C ≌ D) [e.functor.Braided] [e.inverse.Braided] : CommGrp C ≌ CommGrp D

An equivalence of categories lifts to an equivalence of their commutative group objects.

@[simp]

theorem CategoryTheory.Equivalence.mapCommGrp_functor {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] (e : C ≌ D) [e.functor.Braided] [e.inverse.Braided] : e.mapCommGrp.functor = e.functor.mapCommGrp

@[simp]

theorem CategoryTheory.Equivalence.mapCommGrp_unitIso {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] (e : C ≌ D) [e.functor.Braided] [e.inverse.Braided] : e.mapCommGrp.unitIso = Functor.mapCommGrpIdIso.symm ≪≫ Functor.mapCommGrpNatIso e.unitIso ≪≫ Functor.mapCommGrpCompIso

@[simp]

theorem CategoryTheory.Equivalence.mapCommGrp_inverse {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] (e : C ≌ D) [e.functor.Braided] [e.inverse.Braided] : e.mapCommGrp.inverse = e.inverse.mapCommGrp

@[simp]

theorem CategoryTheory.Equivalence.mapCommGrp_counitIso {C : Type u₁} [Category.{v₁, u₁} C] [CartesianMonoidalCategory C] [BraidedCategory C] {D : Type u₂} [Category.{v₂, u₂} D] [CartesianMonoidalCategory D] [BraidedCategory D] (e : C ≌ D) [e.functor.Braided] [e.inverse.Braided] : e.mapCommGrp.counitIso = Functor.mapCommGrpCompIso.symm ≪≫ Functor.mapCommGrpNatIso e.counitIso ≪≫ Functor.mapCommGrpIdIso