Documentation

Mathlib.CategoryTheory.Shift.ShiftSequence

Sequences of functors from a category equipped with a shift

Let F : C ⥤ A be a functor from a category C that is equipped with a shift by an additive monoid M. In this file, we define a typeclass F.ShiftSequence M which includes the data of a sequence of functors F.shift a : C ⥤ A for all a : A. For each a : A, we have an isomorphism F.isoShift a : shiftFunctor C a ⋙ F ≅ F.shift a which satisfies some coherence relations. This allows to state results (e.g. the long exact sequence of an homology functor (TODO)) using functors F.shift a rather than shiftFunctor C a ⋙ F. The reason for this design is that we can often choose functors F.shift a that have better definitional properties than shiftFunctor C a ⋙ F. For example, if C is the derived category (TODO) of an abelian category A and F is the homology functor in degree 0, then for any n : ℤ, we may choose F.shift n to be the homology functor in degree n.

class CategoryTheory.Functor.ShiftSequence {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_5, u_1} C] [CategoryTheory.Category.{u_6, u_2} A] (F : CategoryTheory.Functor C A) (M : Type u_3) [AddMonoid M] [CategoryTheory.HasShift C M] :
Type (max (max (max (max u_1 u_2) u_3) u_5) u_6)

A shift sequence for a functor F : C ⥤ A when C is equipped with a shift by a monoid M involves a sequence of functor sequence n : C ⥤ A for all n : M which behave like shiftFunctor C n ⋙ F.

Instances

    The tautological shift sequence on a functor.

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    • One or more equations did not get rendered due to their size.
    Instances For

      The shifted functors given by the shift sequence.

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      Instances For
        def CategoryTheory.Functor.shiftIso {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_5, u_1} C] [CategoryTheory.Category.{u_6, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] (n : M) (a : M) (a' : M) (ha' : n + a = a') :
        (CategoryTheory.shiftFunctor C n).comp (F.shift a) F.shift a'

        Compatibility isomorphism shiftFunctor C n ⋙ F.shift a ≅ F.shift a' when n + a = a'.

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        Instances For
          @[simp]
          theorem CategoryTheory.Functor.shiftIso_hom_naturality {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_5, u_1} C] [CategoryTheory.Category.{u_6, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] {X : C} {Y : C} (n : M) (a : M) (a' : M) (ha' : n + a = a') (f : X Y) :
          CategoryTheory.CategoryStruct.comp ((F.shift a).map ((CategoryTheory.shiftFunctor C n).map f)) ((F.shiftIso n a a' ha').hom.app Y) = CategoryTheory.CategoryStruct.comp ((F.shiftIso n a a' ha').hom.app X) ((F.shift a').map f)
          @[simp]
          theorem CategoryTheory.Functor.shiftIso_hom_naturality_assoc {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_5, u_1} C] [CategoryTheory.Category.{u_6, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] {X : C} {Y : C} (n : M) (a : M) (a' : M) (ha' : n + a = a') (f : X Y) {Z : A} (h : (F.shift a').obj Y Z) :
          CategoryTheory.CategoryStruct.comp ((F.shift a).map ((CategoryTheory.shiftFunctor C n).map f)) (CategoryTheory.CategoryStruct.comp ((F.shiftIso n a a' ha').hom.app Y) h) = CategoryTheory.CategoryStruct.comp ((F.shiftIso n a a' ha').hom.app X) (CategoryTheory.CategoryStruct.comp ((F.shift a').map f) h)
          @[simp]
          theorem CategoryTheory.Functor.shiftIso_inv_naturality {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_5, u_1} C] [CategoryTheory.Category.{u_6, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] {X : C} {Y : C} (n : M) (a : M) (a' : M) (ha' : n + a = a') (f : X Y) :
          CategoryTheory.CategoryStruct.comp ((F.shift a').map f) ((F.shiftIso n a a' ha').inv.app Y) = CategoryTheory.CategoryStruct.comp ((F.shiftIso n a a' ha').inv.app X) ((F.shift a).map ((CategoryTheory.shiftFunctor C n).map f))
          @[simp]
          theorem CategoryTheory.Functor.shiftIso_inv_naturality_assoc {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_5, u_1} C] [CategoryTheory.Category.{u_6, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] {X : C} {Y : C} (n : M) (a : M) (a' : M) (ha' : n + a = a') (f : X Y) {Z : A} (h : (F.shift a).obj ((CategoryTheory.shiftFunctor C n).obj Y) Z) :
          CategoryTheory.CategoryStruct.comp ((F.shift a').map f) (CategoryTheory.CategoryStruct.comp ((F.shiftIso n a a' ha').inv.app Y) h) = CategoryTheory.CategoryStruct.comp ((F.shiftIso n a a' ha').inv.app X) (CategoryTheory.CategoryStruct.comp ((F.shift a).map ((CategoryTheory.shiftFunctor C n).map f)) h)

          The canonical isomorphism F.shift 0 ≅ F.

          Equations
          • F.isoShiftZero M = CategoryTheory.Functor.ShiftSequence.isoZero
          Instances For

            The canonical isomorphism shiftFunctor C n ⋙ F ≅ F.shift n.

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              @[simp]
              theorem CategoryTheory.Functor.isoShift_hom_naturality {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_5, u_1} C] [CategoryTheory.Category.{u_6, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] (n : M) {X : C} {Y : C} (f : X Y) :
              CategoryTheory.CategoryStruct.comp (F.map ((CategoryTheory.shiftFunctor C n).map f)) ((F.isoShift n).hom.app Y) = CategoryTheory.CategoryStruct.comp ((F.isoShift n).hom.app X) ((F.shift n).map f)
              theorem CategoryTheory.Functor.isoShift_hom_naturality_assoc {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_5, u_1} C] [CategoryTheory.Category.{u_6, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] (n : M) {X : C} {Y : C} (f : X Y) {Z : A} (h : (F.shift n).obj Y Z) :
              theorem CategoryTheory.Functor.isoShift_inv_naturality {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_5, u_1} C] [CategoryTheory.Category.{u_6, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] (n : M) {X : C} {Y : C} (f : X Y) :
              CategoryTheory.CategoryStruct.comp ((F.shift n).map f) ((F.isoShift n).inv.app Y) = CategoryTheory.CategoryStruct.comp ((F.isoShift n).inv.app X) (F.map ((CategoryTheory.shiftFunctor C n).map f))
              theorem CategoryTheory.Functor.isoShift_inv_naturality_assoc {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_5, u_1} C] [CategoryTheory.Category.{u_6, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] (n : M) {X : C} {Y : C} (f : X Y) {Z : A} (h : F.obj ((CategoryTheory.shiftFunctor C n).obj Y) Z) :
              theorem CategoryTheory.Functor.shiftIso_zero {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_6, u_1} C] [CategoryTheory.Category.{u_5, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] (a : M) :
              F.shiftIso 0 a a = CategoryTheory.isoWhiskerRight (CategoryTheory.shiftFunctorZero C M) (F.shift a) ≪≫ (F.shift a).leftUnitor
              @[simp]
              theorem CategoryTheory.Functor.shiftIso_zero_hom_app {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_6, u_1} C] [CategoryTheory.Category.{u_5, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] (a : M) (X : C) :
              (F.shiftIso 0 a a ).hom.app X = (F.shift a).map ((CategoryTheory.shiftFunctorZero C M).hom.app X)
              @[simp]
              theorem CategoryTheory.Functor.shiftIso_zero_inv_app {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_6, u_1} C] [CategoryTheory.Category.{u_5, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] (a : M) (X : C) :
              (F.shiftIso 0 a a ).inv.app X = (F.shift a).map ((CategoryTheory.shiftFunctorZero C M).inv.app X)
              theorem CategoryTheory.Functor.shiftIso_add {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_6, u_1} C] [CategoryTheory.Category.{u_5, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] (n : M) (m : M) (a : M) (a' : M) (a'' : M) (ha' : n + a = a') (ha'' : m + a' = a'') :
              F.shiftIso (m + n) a a'' = CategoryTheory.isoWhiskerRight (CategoryTheory.shiftFunctorAdd C m n) (F.shift a) ≪≫ (CategoryTheory.shiftFunctor C m).associator (CategoryTheory.shiftFunctor C n) (F.shift a) ≪≫ CategoryTheory.isoWhiskerLeft (CategoryTheory.shiftFunctor C m) (F.shiftIso n a a' ha') ≪≫ F.shiftIso m a' a'' ha''
              theorem CategoryTheory.Functor.shiftIso_add_hom_app {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_6, u_1} C] [CategoryTheory.Category.{u_5, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] (n : M) (m : M) (a : M) (a' : M) (a'' : M) (ha' : n + a = a') (ha'' : m + a' = a'') (X : C) :
              (F.shiftIso (m + n) a a'' ).hom.app X = CategoryTheory.CategoryStruct.comp ((F.shift a).map ((CategoryTheory.shiftFunctorAdd C m n).hom.app X)) (CategoryTheory.CategoryStruct.comp ((F.shiftIso n a a' ha').hom.app ((CategoryTheory.shiftFunctor C m).obj X)) ((F.shiftIso m a' a'' ha'').hom.app X))
              theorem CategoryTheory.Functor.shiftIso_add_inv_app {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_6, u_1} C] [CategoryTheory.Category.{u_5, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] (n : M) (m : M) (a : M) (a' : M) (a'' : M) (ha' : n + a = a') (ha'' : m + a' = a'') (X : C) :
              (F.shiftIso (m + n) a a'' ).inv.app X = CategoryTheory.CategoryStruct.comp ((F.shiftIso m a' a'' ha'').inv.app X) (CategoryTheory.CategoryStruct.comp ((F.shiftIso n a a' ha').inv.app ((CategoryTheory.shiftFunctor C m).obj X)) ((F.shift a).map ((CategoryTheory.shiftFunctorAdd C m n).inv.app X)))
              theorem CategoryTheory.Functor.shiftIso_add' {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_6, u_1} C] [CategoryTheory.Category.{u_5, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] (n : M) (m : M) (mn : M) (hnm : m + n = mn) (a : M) (a' : M) (a'' : M) (ha' : n + a = a') (ha'' : m + a' = a'') :
              F.shiftIso mn a a'' = CategoryTheory.isoWhiskerRight (CategoryTheory.shiftFunctorAdd' C m n mn hnm) (F.shift a) ≪≫ (CategoryTheory.shiftFunctor C m).associator (CategoryTheory.shiftFunctor C n) (F.shift a) ≪≫ CategoryTheory.isoWhiskerLeft (CategoryTheory.shiftFunctor C m) (F.shiftIso n a a' ha') ≪≫ F.shiftIso m a' a'' ha''
              theorem CategoryTheory.Functor.shiftIso_add'_hom_app {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_6, u_1} C] [CategoryTheory.Category.{u_5, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] (n : M) (m : M) (mn : M) (hnm : m + n = mn) (a : M) (a' : M) (a'' : M) (ha' : n + a = a') (ha'' : m + a' = a'') (X : C) :
              (F.shiftIso mn a a'' ).hom.app X = CategoryTheory.CategoryStruct.comp ((F.shift a).map ((CategoryTheory.shiftFunctorAdd' C m n mn hnm).hom.app X)) (CategoryTheory.CategoryStruct.comp ((F.shiftIso n a a' ha').hom.app ((CategoryTheory.shiftFunctor C m).obj X)) ((F.shiftIso m a' a'' ha'').hom.app X))
              theorem CategoryTheory.Functor.shiftIso_add'_inv_app {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_6, u_1} C] [CategoryTheory.Category.{u_5, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] (n : M) (m : M) (mn : M) (hnm : m + n = mn) (a : M) (a' : M) (a'' : M) (ha' : n + a = a') (ha'' : m + a' = a'') (X : C) :
              (F.shiftIso mn a a'' ).inv.app X = CategoryTheory.CategoryStruct.comp ((F.shiftIso m a' a'' ha'').inv.app X) (CategoryTheory.CategoryStruct.comp ((F.shiftIso n a a' ha').inv.app ((CategoryTheory.shiftFunctor C m).obj X)) ((F.shift a).map ((CategoryTheory.shiftFunctorAdd' C m n mn hnm).inv.app X)))
              theorem CategoryTheory.Functor.shiftIso_hom_app_comp {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_6, u_1} C] [CategoryTheory.Category.{u_5, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] (n : M) (m : M) (mn : M) (hnm : m + n = mn) (a : M) (a' : M) (a'' : M) (ha' : n + a = a') (ha'' : m + a' = a'') (X : C) :
              CategoryTheory.CategoryStruct.comp ((F.shiftIso n a a' ha').hom.app ((CategoryTheory.shiftFunctor C m).obj X)) ((F.shiftIso m a' a'' ha'').hom.app X) = CategoryTheory.CategoryStruct.comp ((F.shift a).map ((CategoryTheory.shiftFunctorAdd' C m n mn hnm).inv.app X)) ((F.shiftIso mn a a'' ).hom.app X)
              theorem CategoryTheory.Functor.shiftIso_hom_app_comp_assoc {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_6, u_1} C] [CategoryTheory.Category.{u_5, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] (n : M) (m : M) (mn : M) (hnm : m + n = mn) (a : M) (a' : M) (a'' : M) (ha' : n + a = a') (ha'' : m + a' = a'') (X : C) {Z : A} (h : (F.shift a'').obj X Z) :
              CategoryTheory.CategoryStruct.comp ((F.shiftIso n a a' ha').hom.app ((CategoryTheory.shiftFunctor C m).obj X)) (CategoryTheory.CategoryStruct.comp ((F.shiftIso m a' a'' ha'').hom.app X) h) = CategoryTheory.CategoryStruct.comp ((F.shift a).map ((CategoryTheory.shiftFunctorAdd' C m n mn hnm).inv.app X)) (CategoryTheory.CategoryStruct.comp ((F.shiftIso mn a a'' ).hom.app X) h)
              def CategoryTheory.Functor.shiftMap {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_5, u_1} C] [CategoryTheory.Category.{u_6, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] {X : C} {Y : C} {n : M} (f : X (CategoryTheory.shiftFunctor C n).obj Y) (a : M) (a' : M) (ha' : n + a = a') :
              (F.shift a).obj X (F.shift a').obj Y

              The morphism (F.shift a).obj X ⟶ (F.shift a').obj Y induced by a morphism f : X ⟶ Y⟦n⟧ when n + a = a'.

              Equations
              Instances For
                theorem CategoryTheory.Functor.shiftMap_comp {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_5, u_1} C] [CategoryTheory.Category.{u_6, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] {X : C} {Y : C} {Z : C} {n : M} (f : X (CategoryTheory.shiftFunctor C n).obj Y) (g : Y Z) (a : M) (a' : M) (ha' : n + a = a') :
                F.shiftMap (CategoryTheory.CategoryStruct.comp f ((CategoryTheory.shiftFunctor C n).map g)) a a' ha' = CategoryTheory.CategoryStruct.comp (F.shiftMap f a a' ha') ((F.shift a').map g)
                theorem CategoryTheory.Functor.shiftMap_comp_assoc {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_5, u_1} C] [CategoryTheory.Category.{u_6, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] {X : C} {Y : C} {Z : C} {n : M} (f : X (CategoryTheory.shiftFunctor C n).obj Y) (g : Y Z✝) (a : M) (a' : M) (ha' : n + a = a') {Z : A} (h : (F.shift a').obj Z✝ Z) :
                theorem CategoryTheory.Functor.shiftMap_comp' {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_5, u_1} C] [CategoryTheory.Category.{u_6, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] {X : C} {Y : C} {Z : C} {n : M} (f : X Y) (g : Y (CategoryTheory.shiftFunctor C n).obj Z) (a : M) (a' : M) (ha' : n + a = a') :
                F.shiftMap (CategoryTheory.CategoryStruct.comp f g) a a' ha' = CategoryTheory.CategoryStruct.comp ((F.shift a).map f) (F.shiftMap g a a' ha')
                theorem CategoryTheory.Functor.shiftMap_comp'_assoc {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_5, u_1} C] [CategoryTheory.Category.{u_6, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] {X : C} {Y : C} {Z : C} {n : M} (f : X Y) (g : Y (CategoryTheory.shiftFunctor C n).obj Z✝) (a : M) (a' : M) (ha' : n + a = a') {Z : A} (h : (F.shift a').obj Z✝ Z) :
                theorem CategoryTheory.Functor.shiftIso_hom_app_comp_shiftMap {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_5, u_1} C] [CategoryTheory.Category.{u_6, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] {X : C} {Y : C} {m : M} (f : X (CategoryTheory.shiftFunctor C m).obj Y) (n : M) (mn : M) (hnm : m + n = mn) (a : M) (a' : M) (a'' : M) (ha' : n + a = a') (ha'' : m + a' = a'') :
                CategoryTheory.CategoryStruct.comp ((F.shiftIso n a a' ha').hom.app X) (F.shiftMap f a' a'' ha'') = CategoryTheory.CategoryStruct.comp ((F.shift a).map ((CategoryTheory.shiftFunctor C n).map f)) (CategoryTheory.CategoryStruct.comp ((F.shift a).map ((CategoryTheory.shiftFunctorAdd' C m n mn hnm).inv.app Y)) ((F.shiftIso mn a a'' ).hom.app Y))

                When f : X ⟶ Y⟦m⟧, m + n = mn, n + a = a' and ha'' : m + a' = a'', this lemma relates the two morphisms F.shiftMap f a' a'' ha'' and (F.shift a).map (f⟦n⟧'). Indeed, via canonical isomorphisms, they both identity to morphisms (F.shift a').obj X ⟶ (F.shift a'').obj Y.

                theorem CategoryTheory.Functor.shiftIso_hom_app_comp_shiftMap_of_add_eq_zero {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_5, u_1} C] [CategoryTheory.Category.{u_6, u_2} A] (F : CategoryTheory.Functor C A) {G : Type u_4} [AddGroup G] [CategoryTheory.HasShift C G] [F.ShiftSequence G] {X : C} {Y : C} {m : G} (f : X (CategoryTheory.shiftFunctor C m).obj Y) (n : G) (hnm : n + m = 0) (a : G) (a' : G) (ha' : m + a = a') :
                CategoryTheory.CategoryStruct.comp ((F.shiftIso n a' a ).hom.app X) (F.shiftMap f a a' ha') = (F.shift a').map (CategoryTheory.CategoryStruct.comp ((CategoryTheory.shiftFunctor C n).map f) ((CategoryTheory.shiftFunctorCompIsoId C m n ).hom.app Y))

                If f : X ⟶ Y⟦m⟧, n + m = 0 and ha' : m + a = a', this lemma relates the two morphisms F.shiftMap f a a' ha' and (F.shift a').map (f⟦n⟧'). Indeed, via canonical isomorphisms, they both identify to morphisms (F.shift a).obj X ⟶ (F.shift a').obj Y.

                instance CategoryTheory.Functor.instPreservesZeroMorphismsShift {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_5, u_1} C] [CategoryTheory.Category.{u_6, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] [CategoryTheory.Limits.HasZeroMorphisms C] [CategoryTheory.Limits.HasZeroMorphisms A] [F.PreservesZeroMorphisms] [∀ (n : M), (CategoryTheory.shiftFunctor C n).PreservesZeroMorphisms] (n : M) :
                (F.shift n).PreservesZeroMorphisms
                Equations
                • =
                @[simp]
                theorem CategoryTheory.Functor.shiftMap_zero {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_6, u_1} C] [CategoryTheory.Category.{u_5, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] [CategoryTheory.Limits.HasZeroMorphisms C] [CategoryTheory.Limits.HasZeroMorphisms A] [F.PreservesZeroMorphisms] [∀ (n : M), (CategoryTheory.shiftFunctor C n).PreservesZeroMorphisms] (X : C) (Y : C) (n : M) (a : M) (a' : M) (ha' : n + a = a') :
                F.shiftMap 0 a a' ha' = 0
                instance CategoryTheory.Functor.instAdditiveShift {C : Type u_1} {A : Type u_2} [CategoryTheory.Category.{u_5, u_1} C] [CategoryTheory.Category.{u_6, u_2} A] (F : CategoryTheory.Functor C A) {M : Type u_3} [AddMonoid M] [CategoryTheory.HasShift C M] [F.ShiftSequence M] [CategoryTheory.Preadditive C] [CategoryTheory.Preadditive A] [F.Additive] [∀ (n : M), (CategoryTheory.shiftFunctor C n).Additive] (n : M) :
                (F.shift n).Additive
                Equations
                • =