English
The tensor μ morphism evaluated at a pair aligns with the componentwise tensor μ on the underlying objects, reflecting how the tensor structure acts on morphisms.
Русский
Морфизм tensor μ при паре согласуется с компонентной tensor μ на сами объекты, отражая действие тензорной структуры на морфизмах.
LaTeX
$$$$ μ (tensor C) X Y = tensorμ X.1 X.2 Y.1 Y.2. $$$$
Lean4
@[reassoc]
theorem tensorμ_comp_μ_tensorHom_μ_comp_μ (F : C ⥤ D) [F.LaxBraided] (W X Y Z : C) :
tensorμ (F.obj W) (F.obj X) (F.obj Y) (F.obj Z) ≫ (μ F W Y ⊗ₘ μ F X Z) ≫ μ F (W ⊗ Y) (X ⊗ Z) =
(μ F W X ⊗ₘ μ F Y Z) ≫ μ F (W ⊗ X) (Y ⊗ Z) ≫ F.map (tensorμ W X Y Z) :=
by
rw [tensorHom_def]
simp only [tensorμ, Category.assoc]
rw [whiskerLeft_μ_comp_μ, associator_inv_naturality_left_assoc, ← pentagon_inv_assoc, ← comp_whiskerRight_assoc, ←
comp_whiskerRight_assoc, Category.assoc, μ_whiskerRight_comp_μ, whiskerLeft_hom_inv_assoc, Iso.inv_hom_id_assoc,
comp_whiskerRight_assoc, comp_whiskerRight_assoc, μ_natural_left_assoc, associator_inv_naturality_middle_assoc, ←
comp_whiskerRight_assoc, ← comp_whiskerRight_assoc, ← MonoidalCategory.whiskerLeft_comp, ←
Functor.LaxBraided.braided, MonoidalCategory.whiskerLeft_comp_assoc, μ_natural_right, whiskerLeft_μ_comp_μ_assoc,
comp_whiskerRight_assoc, comp_whiskerRight_assoc, comp_whiskerRight_assoc, comp_whiskerRight_assoc,
pentagon_inv_assoc, μ_natural_left_assoc, μ_natural_left_assoc, Iso.hom_inv_id_assoc, ←
associator_inv_naturality_left_assoc, μ_whiskerRight_comp_μ_assoc, Iso.inv_hom_id_assoc, ← tensorHom_def_assoc]
simp only [← Functor.map_comp, whisker_assoc, Category.assoc, pentagon_inv_inv_hom_hom_inv,
pentagon_inv_hom_hom_hom_inv_assoc]