Monoidal natural transformations #
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Natural transformations between (lax) monoidal functors must satisfy
an additional compatibility relation with the tensorators:
F.μ X Y ≫ app (X ⊗ Y) = (app X ⊗ app Y) ≫ G.μ X Y
.
(Lax) monoidal functors between a fixed pair of monoidal categories themselves form a category.
- to_nat_trans : category_theory.nat_trans F.to_functor G.to_functor
- unit' : F.ε ≫ self.to_nat_trans.app (𝟙_ C) = G.ε . "obviously"
- tensor' : (∀ (X Y : C), F.μ X Y ≫ self.to_nat_trans.app (X ⊗ Y) = (self.to_nat_trans.app X ⊗ self.to_nat_trans.app Y) ≫ G.μ X Y) . "obviously"
A monoidal natural transformation is a natural transformation between (lax) monoidal functors
additionally satisfying:
F.μ X Y ≫ app (X ⊗ Y) = (app X ⊗ app Y) ≫ G.μ X Y
Instances for category_theory.monoidal_nat_trans
- category_theory.monoidal_nat_trans.has_sizeof_inst
- category_theory.monoidal_nat_trans.inhabited
The identity monoidal natural transformation.
Equations
- category_theory.monoidal_nat_trans.id F = {to_nat_trans := {app := (𝟙 F.to_functor).app, naturality' := _}, unit' := _, tensor' := _}
Vertical composition of monoidal natural transformations.
Equations
- α.vcomp β = {to_nat_trans := {app := (α.to_nat_trans.vcomp β.to_nat_trans).app, naturality' := _}, unit' := _, tensor' := _}
Equations
- category_theory.monoidal_nat_trans.category_lax_monoidal_functor = {to_category_struct := {to_quiver := {hom := category_theory.monoidal_nat_trans _inst_4}, id := category_theory.monoidal_nat_trans.id _inst_4, comp := λ (F G H : category_theory.lax_monoidal_functor C D) (α : F ⟶ G) (β : G ⟶ H), category_theory.monoidal_nat_trans.vcomp α β}, id_comp' := _, comp_id' := _, assoc' := _}
Horizontal composition of monoidal natural transformations.
Equations
- α.hcomp β = {to_nat_trans := {app := (α.to_nat_trans ◫ β.to_nat_trans).app, naturality' := _}, unit' := _, tensor' := _}
The cartesian product of two monoidal natural transformations is monoidal.
Equations
- α.prod β = {to_nat_trans := {app := λ (X : C), (α.to_nat_trans.app X, β.to_nat_trans.app X), naturality' := _}, unit' := _, tensor' := _}
Construct a monoidal natural isomorphism from object level isomorphisms, and the monoidal naturality in the forward direction.
Equations
- category_theory.monoidal_nat_iso.of_components app naturality unit tensor = {hom := {to_nat_trans := {app := λ (X : C), (app X).hom, naturality' := naturality}, unit' := unit, tensor' := tensor}, inv := {to_nat_trans := {app := λ (X : C), (app X).inv, naturality' := _}, unit' := _, tensor' := _}, hom_inv_id' := _, inv_hom_id' := _}
The unit of a monoidal equivalence can be upgraded to a monoidal natural transformation.
Equations
- category_theory.monoidal_unit F = let e : C ≌ D := F.to_lax_monoidal_functor.to_functor.as_equivalence in {to_nat_trans := e.unit, unit' := _, tensor' := _}
Instances for category_theory.monoidal_unit
The counit of a monoidal equivalence can be upgraded to a monoidal natural transformation.
Equations
- category_theory.monoidal_counit F = let e : C ≌ D := F.to_lax_monoidal_functor.to_functor.as_equivalence in {to_nat_trans := e.counit, unit' := _, tensor' := _}