Homological complexes are differential graded objects. #
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We verify that a homological_complex
indexed by an add_comm_group
is
essentially the same thing as a differential graded object.
This equivalence is probably not particularly useful in practice; it's here to check that definitions match up as expected.
Since eq_to_hom
only preserves the fact that X.X i = X.X j
but not i = j
, this definition
is used to aid the simplifier.
The functor from differential graded objects to homological complexes.
Equations
- homological_complex.dgo_to_homological_complex b V = {obj := λ (X : category_theory.differential_object (category_theory.graded_object_with_shift b V)), {X := λ (i : β), X.X i, d := λ (i j : β), dite (i + b = j) (λ (h : i + b = j), X.d i ≫ X.X_eq_to_hom _) (λ (h : ¬i + b = j), 0), shape' := _, d_comp_d' := _}, map := λ (X Y : category_theory.differential_object (category_theory.graded_object_with_shift b V)) (f : X ⟶ Y), {f := f.f, comm' := _}, map_id' := _, map_comp' := _}
The functor from homological complexes to differential graded objects.
Equations
- homological_complex.homological_complex_to_dgo b V = {obj := λ (X : homological_complex V (complex_shape.up' b)), {X := λ (i : β), X.X i, d := λ (i : β), X.d i (i + 1 • b), d_squared' := _}, map := λ (X Y : homological_complex V (complex_shape.up' b)) (f : X ⟶ Y), {f := f.f, comm' := _}, map_id' := _, map_comp' := _}
The unit isomorphism for dgo_equiv_homological_complex
.
Equations
- homological_complex.dgo_equiv_homological_complex_unit_iso b V = category_theory.nat_iso.of_components (λ (X : category_theory.differential_object (category_theory.graded_object_with_shift b V)), {hom := {f := λ (i : β), 𝟙 (X.X i), comm' := _}, inv := {f := λ (i : β), 𝟙 (X.X i), comm' := _}, hom_inv_id' := _, inv_hom_id' := _}) _
The counit isomorphism for dgo_equiv_homological_complex
.
Equations
- homological_complex.dgo_equiv_homological_complex_counit_iso b V = category_theory.nat_iso.of_components (λ (X : homological_complex V (complex_shape.up' b)), {hom := {f := λ (i : β), 𝟙 (X.X i), comm' := _}, inv := {f := λ (i : β), 𝟙 (X.X i), comm' := _}, hom_inv_id' := _, inv_hom_id' := _}) _
The category of differential graded objects in V
is equivalent
to the category of homological complexes in V
.
Equations
- homological_complex.dgo_equiv_homological_complex b V = {functor := homological_complex.dgo_to_homological_complex b V _inst_3, inverse := homological_complex.homological_complex_to_dgo b V _inst_3, unit_iso := homological_complex.dgo_equiv_homological_complex_unit_iso b V _inst_3, counit_iso := homological_complex.dgo_equiv_homological_complex_counit_iso b V _inst_3, functor_unit_iso_comp' := _}