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mul_equiv.multiplicative_additive [mul_one_class H] : multiplicative (additive H) ≃* H
add_equiv.to_multiplicative'' (add_equiv.refl (additive H))
def
mul_equiv.multiplicative_additive
algebra.hom.equiv
src/algebra/hom/equiv/type_tags.lean
[ "algebra.hom.equiv.basic", "algebra.group.type_tags" ]
[ "add_equiv.to_multiplicative''", "additive", "mul_one_class", "multiplicative" ]
`multiplicative (additive H)` is just `H`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
to_units [group G] : G ≃* Gˣ
{ to_fun := λ x, ⟨x, x⁻¹, mul_inv_self _, inv_mul_self _⟩, inv_fun := coe, left_inv := λ x, rfl, right_inv := λ u, units.ext rfl, map_mul' := λ x y, units.ext rfl }
def
to_units
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[ "group", "inv_fun", "inv_mul_self", "mul_inv_self", "units.ext" ]
A group is isomorphic to its group of units.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_to_units [group G] (g : G) : (to_units g : G) = g
rfl
lemma
coe_to_units
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[ "group", "to_units" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
map_equiv (h : M ≃* N) : Mˣ ≃* Nˣ
{ inv_fun := map h.symm.to_monoid_hom, left_inv := λ u, ext $ h.left_inv u, right_inv := λ u, ext $ h.right_inv u, .. map h.to_monoid_hom }
def
units.map_equiv
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[ "inv_fun" ]
A multiplicative equivalence of monoids defines a multiplicative equivalence of their groups of units.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
map_equiv_symm (h : M ≃* N) : (map_equiv h).symm = map_equiv h.symm
rfl
lemma
units.map_equiv_symm
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_map_equiv (h : M ≃* N) (x : Mˣ) : (map_equiv h x : N) = h x
rfl
lemma
units.coe_map_equiv
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_left (u : Mˣ) : equiv.perm M
{ to_fun := λx, u * x, inv_fun := λx, ↑u⁻¹ * x, left_inv := u.inv_mul_cancel_left, right_inv := u.mul_inv_cancel_left }
def
units.mul_left
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[ "equiv.perm", "inv_fun" ]
Left multiplication by a unit of a monoid is a permutation of the underlying type.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_left_symm (u : Mˣ) : u.mul_left.symm = u⁻¹.mul_left
equiv.ext $ λ x, rfl
lemma
units.mul_left_symm
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[ "equiv.ext" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_left_bijective (a : Mˣ) : function.bijective ((*) a : M → M)
(mul_left a).bijective
lemma
units.mul_left_bijective
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_right (u : Mˣ) : equiv.perm M
{ to_fun := λx, x * u, inv_fun := λx, x * ↑u⁻¹, left_inv := λ x, mul_inv_cancel_right x u, right_inv := λ x, inv_mul_cancel_right x u }
def
units.mul_right
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[ "equiv.perm", "inv_fun", "inv_mul_cancel_right", "mul_inv_cancel_right" ]
Right multiplication by a unit of a monoid is a permutation of the underlying type.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_right_symm (u : Mˣ) : u.mul_right.symm = u⁻¹.mul_right
equiv.ext $ λ x, rfl
lemma
units.mul_right_symm
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[ "equiv.ext" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_right_bijective (a : Mˣ) : function.bijective ((* a) : M → M)
(mul_right a).bijective
lemma
units.mul_right_bijective
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_left (a : G) : perm G
(to_units a).mul_left
def
equiv.mul_left
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[ "to_units" ]
Left multiplication in a `group` is a permutation of the underlying type.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_mul_left (a : G) : ⇑(equiv.mul_left a) = (*) a
rfl
lemma
equiv.coe_mul_left
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[ "equiv.mul_left" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_left_symm_apply (a : G) : ((equiv.mul_left a).symm : G → G) = (*) a⁻¹
rfl
lemma
equiv.mul_left_symm_apply
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[ "equiv.mul_left" ]
Extra simp lemma that `dsimp` can use. `simp` will never use this.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_left_symm (a : G) : (equiv.mul_left a).symm = equiv.mul_left a⁻¹
ext $ λ x, rfl
lemma
equiv.mul_left_symm
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[ "equiv.mul_left" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
_root_.group.mul_left_bijective (a : G) : function.bijective ((*) a)
(equiv.mul_left a).bijective
lemma
group.mul_left_bijective
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[ "equiv.mul_left" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_right (a : G) : perm G
(to_units a).mul_right
def
equiv.mul_right
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[ "to_units" ]
Right multiplication in a `group` is a permutation of the underlying type.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_mul_right (a : G) : ⇑(equiv.mul_right a) = λ x, x * a
rfl
lemma
equiv.coe_mul_right
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[ "equiv.mul_right" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_right_symm (a : G) : (equiv.mul_right a).symm = equiv.mul_right a⁻¹
ext $ λ x, rfl
lemma
equiv.mul_right_symm
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[ "equiv.mul_right" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_right_symm_apply (a : G) : ((equiv.mul_right a).symm : G → G) = λ x, x * a⁻¹
rfl
lemma
equiv.mul_right_symm_apply
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[ "equiv.mul_right" ]
Extra simp lemma that `dsimp` can use. `simp` will never use this.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
_root_.group.mul_right_bijective (a : G) : function.bijective (* a)
(equiv.mul_right a).bijective
lemma
group.mul_right_bijective
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[ "equiv.mul_right" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
div_left (a : G) : G ≃ G
{ to_fun := λ b, a / b, inv_fun := λ b, b⁻¹ * a, left_inv := λ b, by simp [div_eq_mul_inv], right_inv := λ b, by simp [div_eq_mul_inv] }
def
equiv.div_left
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[ "div_eq_mul_inv", "inv_fun" ]
A version of `equiv.mul_left a b⁻¹` that is defeq to `a / b`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
div_left_eq_inv_trans_mul_left (a : G) : equiv.div_left a = (equiv.inv G).trans (equiv.mul_left a)
ext $ λ _, div_eq_mul_inv _ _
lemma
equiv.div_left_eq_inv_trans_mul_left
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[ "div_eq_mul_inv", "equiv.div_left", "equiv.inv", "equiv.mul_left" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
div_right (a : G) : G ≃ G
{ to_fun := λ b, b / a, inv_fun := λ b, b * a, left_inv := λ b, by simp [div_eq_mul_inv], right_inv := λ b, by simp [div_eq_mul_inv] }
def
equiv.div_right
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[ "div_eq_mul_inv", "inv_fun" ]
A version of `equiv.mul_right a⁻¹ b` that is defeq to `b / a`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
div_right_eq_mul_right_inv (a : G) : equiv.div_right a = equiv.mul_right a⁻¹
ext $ λ _, div_eq_mul_inv _ _
lemma
equiv.div_right_eq_mul_right_inv
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[ "div_eq_mul_inv", "equiv.div_right", "equiv.mul_right" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_equiv.inv (G : Type*) [division_comm_monoid G] : G ≃* G
{ to_fun := has_inv.inv, inv_fun := has_inv.inv, map_mul' := mul_inv, ..equiv.inv G }
def
mul_equiv.inv
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[ "division_comm_monoid", "equiv.inv", "inv_fun", "mul_inv" ]
In a `division_comm_monoid`, `equiv.inv` is a `mul_equiv`. There is a variant of this `mul_equiv.inv' G : G ≃* Gᵐᵒᵖ` for the non-commutative case.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_equiv.inv_symm (G : Type*) [division_comm_monoid G] : (mul_equiv.inv G).symm = mul_equiv.inv G
rfl
lemma
mul_equiv.inv_symm
algebra.hom.equiv.units
src/algebra/hom/equiv/units/basic.lean
[ "algebra.hom.equiv.basic", "algebra.hom.units" ]
[ "division_comm_monoid", "mul_equiv.inv" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_left₀ (a : G) (ha : a ≠ 0) : perm G
(units.mk0 a ha).mul_left
def
equiv.mul_left₀
algebra.hom.equiv.units
src/algebra/hom/equiv/units/group_with_zero.lean
[ "algebra.hom.equiv.units.basic", "algebra.group_with_zero.units.basic" ]
[ "units.mk0" ]
Left multiplication by a nonzero element in a `group_with_zero` is a permutation of the underlying type.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
_root_.mul_left_bijective₀ (a : G) (ha : a ≠ 0) : function.bijective ((*) a : G → G)
(equiv.mul_left₀ a ha).bijective
lemma
mul_left_bijective₀
algebra.hom.equiv.units
src/algebra/hom/equiv/units/group_with_zero.lean
[ "algebra.hom.equiv.units.basic", "algebra.group_with_zero.units.basic" ]
[ "equiv.mul_left₀" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_right₀ (a : G) (ha : a ≠ 0) : perm G
(units.mk0 a ha).mul_right
def
equiv.mul_right₀
algebra.hom.equiv.units
src/algebra/hom/equiv/units/group_with_zero.lean
[ "algebra.hom.equiv.units.basic", "algebra.group_with_zero.units.basic" ]
[ "units.mk0" ]
Right multiplication by a nonzero element in a `group_with_zero` is a permutation of the underlying type.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
_root_.mul_right_bijective₀ (a : G) (ha : a ≠ 0) : function.bijective ((* a) : G → G)
(equiv.mul_right₀ a ha).bijective
lemma
mul_right_bijective₀
algebra.hom.equiv.units
src/algebra/hom/equiv/units/group_with_zero.lean
[ "algebra.hom.equiv.units.basic", "algebra.group_with_zero.units.basic" ]
[ "equiv.mul_right₀" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
has_nat_scalar : has_smul ℕ (C ⟶ D)
⟨λ n f, { f := λ i, n • f.f i, comm' := λ i j h, by simp [preadditive.nsmul_comp, preadditive.comp_nsmul] }⟩
instance
homological_complex.has_nat_scalar
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[ "has_smul" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
has_int_scalar : has_smul ℤ (C ⟶ D)
⟨λ n f, { f := λ i, n • f.f i, comm' := λ i j h, by simp [preadditive.zsmul_comp, preadditive.comp_zsmul] }⟩
instance
homological_complex.has_int_scalar
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[ "has_smul" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
zero_f_apply (i : ι) : (0 : C ⟶ D).f i = 0
rfl
lemma
homological_complex.zero_f_apply
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
add_f_apply (f g : C ⟶ D) (i : ι) : (f + g).f i = f.f i + g.f i
rfl
lemma
homological_complex.add_f_apply
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
neg_f_apply (f : C ⟶ D) (i : ι) : (-f).f i = -(f.f i)
rfl
lemma
homological_complex.neg_f_apply
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sub_f_apply (f g : C ⟶ D) (i : ι) : (f - g).f i = f.f i - g.f i
rfl
lemma
homological_complex.sub_f_apply
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
nsmul_f_apply (n : ℕ) (f : C ⟶ D) (i : ι) : (n • f).f i = n • f.f i
rfl
lemma
homological_complex.nsmul_f_apply
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
zsmul_f_apply (n : ℤ) (f : C ⟶ D) (i : ι) : (n • f).f i = n • f.f i
rfl
lemma
homological_complex.zsmul_f_apply
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
hom.f_add_monoid_hom {C₁ C₂ : homological_complex V c} (i : ι) : (C₁ ⟶ C₂) →+ (C₁.X i ⟶ C₂.X i)
add_monoid_hom.mk' (λ f, hom.f f i) (λ _ _, rfl)
def
homological_complex.hom.f_add_monoid_hom
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[ "homological_complex" ]
The `i`-th component of a chain map, as an additive map from chain maps to morphisms.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
eval_additive (i : ι) : (eval V c i).additive
{}
instance
homological_complex.eval_additive
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[ "additive" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
cycles_additive [has_equalizers V] : (cycles_functor V c i).additive
{}
instance
homological_complex.cycles_additive
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[ "additive", "cycles_functor" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
boundaries_additive : (boundaries_functor V c i).additive
{}
instance
homological_complex.boundaries_additive
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[ "additive", "boundaries_functor" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
homology_additive : (homology_functor V c i).additive
{ map_add' := λ C D f g, begin dsimp [homology_functor], ext, simp only [homology.π_map, preadditive.comp_add, ←preadditive.add_comp], congr, ext, simp, end }
instance
homological_complex.homology_additive
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[ "additive", "homology.π_map", "homology_functor" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
functor.map_homological_complex (F : V ⥤ W) [F.additive] (c : complex_shape ι) : homological_complex V c ⥤ homological_complex W c
{ obj := λ C, { X := λ i, F.obj (C.X i), d := λ i j, F.map (C.d i j), shape' := λ i j w, by rw [C.shape _ _ w, F.map_zero], d_comp_d' := λ i j k _ _, by rw [←F.map_comp, C.d_comp_d, F.map_zero], }, map := λ C D f, { f := λ i, F.map (f.f i), comm' := λ i j h, by { dsimp, rw [←F.map_comp, ←F.map_co...
def
category_theory.functor.map_homological_complex
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[ "complex_shape", "homological_complex" ]
An additive functor induces a functor between homological complexes. This is sometimes called the "prolongation".
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
functor.map_homological_complex_id_iso (c : complex_shape ι) : (𝟭 V).map_homological_complex c ≅ 𝟭 _
nat_iso.of_components (λ K, hom.iso_of_components (λ i, iso.refl _) (by tidy)) (by tidy)
def
category_theory.functor.map_homological_complex_id_iso
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[ "complex_shape" ]
The functor on homological complexes induced by the identity functor is isomorphic to the identity functor.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
functor.map_homogical_complex_additive (F : V ⥤ W) [F.additive] (c : complex_shape ι) : (F.map_homological_complex c).additive
{}
instance
category_theory.functor.map_homogical_complex_additive
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[ "additive", "complex_shape" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
functor.map_homological_complex_reflects_iso (F : V ⥤ W) [F.additive] [reflects_isomorphisms F] (c : complex_shape ι) : reflects_isomorphisms (F.map_homological_complex c)
⟨λ X Y f, begin introI, haveI : ∀ (n : ι), is_iso (F.map (f.f n)) := λ n, is_iso.of_iso ((homological_complex.eval W c n).map_iso (as_iso ((F.map_homological_complex c).map f))), haveI := λ n, is_iso_of_reflects_iso (f.f n) F, exact homological_complex.hom.is_iso_of_components f, end⟩
instance
category_theory.functor.map_homological_complex_reflects_iso
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[ "complex_shape", "homological_complex.eval", "homological_complex.hom.is_iso_of_components" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
nat_trans.map_homological_complex {F G : V ⥤ W} [F.additive] [G.additive] (α : F ⟶ G) (c : complex_shape ι) : F.map_homological_complex c ⟶ G.map_homological_complex c
{ app := λ C, { f := λ i, α.app _, }, }
def
category_theory.nat_trans.map_homological_complex
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[ "complex_shape" ]
A natural transformation between functors induces a natural transformation between those functors applied to homological complexes.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
nat_trans.map_homological_complex_id (c : complex_shape ι) (F : V ⥤ W) [F.additive] : nat_trans.map_homological_complex (𝟙 F) c = 𝟙 (F.map_homological_complex c)
by tidy
lemma
category_theory.nat_trans.map_homological_complex_id
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[ "complex_shape" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
nat_trans.map_homological_complex_comp (c : complex_shape ι) {F G H : V ⥤ W} [F.additive] [G.additive] [H.additive] (α : F ⟶ G) (β : G ⟶ H): nat_trans.map_homological_complex (α ≫ β) c = nat_trans.map_homological_complex α c ≫ nat_trans.map_homological_complex β c
by tidy
lemma
category_theory.nat_trans.map_homological_complex_comp
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[ "complex_shape" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
nat_trans.map_homological_complex_naturality {c : complex_shape ι} {F G : V ⥤ W} [F.additive] [G.additive] (α : F ⟶ G) {C D : homological_complex V c} (f : C ⟶ D) : (F.map_homological_complex c).map f ≫ (nat_trans.map_homological_complex α c).app D = (nat_trans.map_homological_complex α c).app C ≫ (G.map_homolo...
by tidy
lemma
category_theory.nat_trans.map_homological_complex_naturality
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[ "complex_shape", "homological_complex" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
nat_iso.map_homological_complex {F G : V ⥤ W} [F.additive] [G.additive] (α : F ≅ G) (c : complex_shape ι) : F.map_homological_complex c ≅ G.map_homological_complex c
{ hom := α.hom.map_homological_complex c, inv := α.inv.map_homological_complex c, hom_inv_id' := by simpa only [← nat_trans.map_homological_complex_comp, α.hom_inv_id], inv_hom_id' := by simpa only [← nat_trans.map_homological_complex_comp, α.inv_hom_id], }
def
category_theory.nat_iso.map_homological_complex
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[ "complex_shape" ]
A natural isomorphism between functors induces a natural isomorphism between those functors applied to homological complexes.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
equivalence.map_homological_complex (e : V ≌ W) [e.functor.additive] (c : complex_shape ι): homological_complex V c ≌ homological_complex W c
{ functor := e.functor.map_homological_complex c, inverse := e.inverse.map_homological_complex c, unit_iso := (functor.map_homological_complex_id_iso V c).symm ≪≫ nat_iso.map_homological_complex e.unit_iso c, counit_iso := nat_iso.map_homological_complex e.counit_iso c ≪≫ functor.map_homological_complex_i...
def
category_theory.equivalence.map_homological_complex
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[ "complex_shape", "homological_complex" ]
An equivalence of categories induces an equivalences between the respective categories of homological complex.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
map_chain_complex_of (F : V ⥤ W) [F.additive] (X : α → V) (d : Π n, X (n+1) ⟶ X n) (sq : ∀ n, d (n+1) ≫ d n = 0) : (F.map_homological_complex _).obj (chain_complex.of X d sq) = chain_complex.of (λ n, F.obj (X n)) (λ n, F.map (d n)) (λ n, by rw [ ← F.map_comp, sq n, functor.map_zero])
begin refine homological_complex.ext rfl _, rintro i j (rfl : j + 1 = i), simp only [category_theory.functor.map_homological_complex_obj_d, of_d, eq_to_hom_refl, comp_id, id_comp], end
lemma
chain_complex.map_chain_complex_of
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[ "chain_complex.of", "homological_complex.ext" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
single_map_homological_complex (F : V ⥤ W) [F.additive] (c : complex_shape ι) (j : ι): single V c j ⋙ F.map_homological_complex _ ≅ F ⋙ single W c j
nat_iso.of_components (λ X, { hom := { f := λ i, if h : i = j then eq_to_hom (by simp [h]) else 0, }, inv := { f := λ i, if h : i = j then eq_to_hom (by simp [h]) else 0, }, hom_inv_id' := begin ext i, dsimp, split_ifs with h, { simp [h] }, { rw [zero_comp, if_neg h], e...
def
homological_complex.single_map_homological_complex
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[ "complex_shape" ]
Turning an object into a complex supported at `j` then applying a functor is the same as applying the functor then forming the complex.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
single_map_homological_complex_hom_app_self (j : ι) (X : V) : ((single_map_homological_complex F c j).hom.app X).f j = eq_to_hom (by simp)
by simp [single_map_homological_complex]
lemma
homological_complex.single_map_homological_complex_hom_app_self
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
single_map_homological_complex_hom_app_ne {i j : ι} (h : i ≠ j) (X : V) : ((single_map_homological_complex F c j).hom.app X).f i = 0
by simp [single_map_homological_complex, h]
lemma
homological_complex.single_map_homological_complex_hom_app_ne
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
single_map_homological_complex_inv_app_self (j : ι) (X : V) : ((single_map_homological_complex F c j).inv.app X).f j = eq_to_hom (by simp)
by simp [single_map_homological_complex]
lemma
homological_complex.single_map_homological_complex_inv_app_self
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
single_map_homological_complex_inv_app_ne {i j : ι} (h : i ≠ j) (X : V): ((single_map_homological_complex F c j).inv.app X).f i = 0
by simp [single_map_homological_complex, h]
lemma
homological_complex.single_map_homological_complex_inv_app_ne
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
single₀_map_homological_complex (F : V ⥤ W) [F.additive] : single₀ V ⋙ F.map_homological_complex _ ≅ F ⋙ single₀ W
nat_iso.of_components (λ X, { hom := { f := λ i, match i with | 0 := 𝟙 _ | (i+1) := F.map_zero_object.hom end, }, inv := { f := λ i, match i with | 0 := 𝟙 _ | (i+1) := F.map_zero_object.inv end, }, hom_inv_id' := begin ext (_|i), { unfold_aux, simp, }, { unfold_aux, dsimp...
def
chain_complex.single₀_map_homological_complex
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[]
Turning an object into a chain complex supported at zero then applying a functor is the same as applying the functor then forming the complex.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
single₀_map_homological_complex_hom_app_zero (F : V ⥤ W) [F.additive] (X : V) : ((single₀_map_homological_complex F).hom.app X).f 0 = 𝟙 _
rfl
lemma
chain_complex.single₀_map_homological_complex_hom_app_zero
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
single₀_map_homological_complex_hom_app_succ (F : V ⥤ W) [F.additive] (X : V) (n : ℕ) : ((single₀_map_homological_complex F).hom.app X).f (n+1) = 0
rfl
lemma
chain_complex.single₀_map_homological_complex_hom_app_succ
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
single₀_map_homological_complex_inv_app_zero (F : V ⥤ W) [F.additive] (X : V) : ((single₀_map_homological_complex F).inv.app X).f 0 = 𝟙 _
rfl
lemma
chain_complex.single₀_map_homological_complex_inv_app_zero
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
single₀_map_homological_complex_inv_app_succ (F : V ⥤ W) [F.additive] (X : V) (n : ℕ) : ((single₀_map_homological_complex F).inv.app X).f (n+1) = 0
rfl
lemma
chain_complex.single₀_map_homological_complex_inv_app_succ
algebra.homology
src/algebra/homology/additive.lean
[ "algebra.homology.homology", "algebra.homology.single", "category_theory.preadditive.additive_functor" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
truncate [has_zero_morphisms V] : chain_complex V ℕ ⥤ chain_complex V ℕ
{ obj := λ C, { X := λ i, C.X (i+1), d := λ i j, C.d (i+1) (j+1), shape' := λ i j w, by { apply C.shape, simpa }, }, map := λ C D f, { f := λ i, f.f (i+1), }, }
def
chain_complex.truncate
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "chain_complex" ]
The truncation of a `ℕ`-indexed chain complex, deleting the object at `0` and shifting everything else down.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
truncate_to [has_zero_object V] [has_zero_morphisms V] (C : chain_complex V ℕ) : truncate.obj C ⟶ (single₀ V).obj (C.X 0)
(to_single₀_equiv (truncate.obj C) (C.X 0)).symm ⟨C.d 1 0, by tidy⟩
def
chain_complex.truncate_to
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "chain_complex" ]
There is a canonical chain map from the truncation of a chain map `C` to the "single object" chain complex consisting of the truncated object `C.X 0` in degree 0. The components of this chain map are `C.d 1 0` in degree 0, and zero otherwise.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
augment (C : chain_complex V ℕ) {X : V} (f : C.X 0 ⟶ X) (w : C.d 1 0 ≫ f = 0) : chain_complex V ℕ
{ X := λ i, match i with | 0 := X | (i+1) := C.X i end, d := λ i j, match i, j with | 1, 0 := f | (i+1), (j+1) := C.d i j | _, _ := 0 end, shape' := λ i j s, begin simp at s, rcases i with _|_|i; cases j; unfold_aux; try { simp }, { simpa using s, }, { rw [C.shape], simpa [← ne.def, na...
def
chain_complex.augment
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "chain_complex", "nat.succ_ne_succ" ]
We can "augment" a chain complex by inserting an arbitrary object in degree zero (shifting everything else up), along with a suitable differential.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
augment_X_zero (C : chain_complex V ℕ) {X : V} (f : C.X 0 ⟶ X) (w : C.d 1 0 ≫ f = 0) : (augment C f w).X 0 = X
rfl
lemma
chain_complex.augment_X_zero
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "chain_complex" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
augment_X_succ (C : chain_complex V ℕ) {X : V} (f : C.X 0 ⟶ X) (w : C.d 1 0 ≫ f = 0) (i : ℕ) : (augment C f w).X (i+1) = C.X i
rfl
lemma
chain_complex.augment_X_succ
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "chain_complex" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
augment_d_one_zero (C : chain_complex V ℕ) {X : V} (f : C.X 0 ⟶ X) (w : C.d 1 0 ≫ f = 0) : (augment C f w).d 1 0 = f
rfl
lemma
chain_complex.augment_d_one_zero
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "chain_complex" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
augment_d_succ_succ (C : chain_complex V ℕ) {X : V} (f : C.X 0 ⟶ X) (w : C.d 1 0 ≫ f = 0) (i j : ℕ) : (augment C f w).d (i+1) (j+1) = C.d i j
by { dsimp [augment], rcases i with _|i, refl, refl, }
lemma
chain_complex.augment_d_succ_succ
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "chain_complex" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
truncate_augment (C : chain_complex V ℕ) {X : V} (f : C.X 0 ⟶ X) (w : C.d 1 0 ≫ f = 0) : truncate.obj (augment C f w) ≅ C
{ hom := { f := λ i, 𝟙 _, }, inv := { f := λ i, by { exact 𝟙 _, }, comm' := λ i j, by { cases j; { dsimp, simp, }, }, }, hom_inv_id' := by { ext i, cases i; { dsimp, simp, }, }, inv_hom_id' := by { ext i, cases i; { dsimp, simp, }, }, }.
def
chain_complex.truncate_augment
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "chain_complex" ]
Truncating an augmented chain complex is isomorphic (with components the identity) to the original complex.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
truncate_augment_hom_f (C : chain_complex V ℕ) {X : V} (f : C.X 0 ⟶ X) (w : C.d 1 0 ≫ f = 0) (i : ℕ) : (truncate_augment C f w).hom.f i = 𝟙 (C.X i)
rfl
lemma
chain_complex.truncate_augment_hom_f
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "chain_complex" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
truncate_augment_inv_f (C : chain_complex V ℕ) {X : V} (f : C.X 0 ⟶ X) (w : C.d 1 0 ≫ f = 0) (i : ℕ) : (truncate_augment C f w).inv.f i = 𝟙 ((truncate.obj (augment C f w)).X i)
rfl
lemma
chain_complex.truncate_augment_inv_f
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "chain_complex" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
chain_complex_d_succ_succ_zero (C : chain_complex V ℕ) (i : ℕ) : C.d (i+2) 0 = 0
by { rw C.shape, simpa using i.succ_succ_ne_one.symm }
lemma
chain_complex.chain_complex_d_succ_succ_zero
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "chain_complex" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
augment_truncate (C : chain_complex V ℕ) : augment (truncate.obj C) (C.d 1 0) (C.d_comp_d _ _ _) ≅ C
{ hom := { f := λ i, by { cases i; exact 𝟙 _, }, comm' := λ i j, by { rcases i with _|_|i; cases j; { dsimp, simp, }, }, }, inv := { f := λ i, by { cases i; exact 𝟙 _, }, comm' := λ i j, by { rcases i with _|_|i; cases j; { dsimp, simp, }, }, }, hom_inv_id' := by { ext i, cases i; { dsimp, simp, }, },...
def
chain_complex.augment_truncate
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "chain_complex" ]
Augmenting a truncated complex with the original object and morphism is isomorphic (with components the identity) to the original complex.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
augment_truncate_hom_f_zero (C : chain_complex V ℕ) : (augment_truncate C).hom.f 0 = 𝟙 (C.X 0)
rfl
lemma
chain_complex.augment_truncate_hom_f_zero
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "chain_complex" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
augment_truncate_hom_f_succ (C : chain_complex V ℕ) (i : ℕ) : (augment_truncate C).hom.f (i+1) = 𝟙 (C.X (i+1))
rfl
lemma
chain_complex.augment_truncate_hom_f_succ
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "chain_complex" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
augment_truncate_inv_f_zero (C : chain_complex V ℕ) : (augment_truncate C).inv.f 0 = 𝟙 (C.X 0)
rfl
lemma
chain_complex.augment_truncate_inv_f_zero
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "chain_complex" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
augment_truncate_inv_f_succ (C : chain_complex V ℕ) (i : ℕ) : (augment_truncate C).inv.f (i+1) = 𝟙 (C.X (i+1))
rfl
lemma
chain_complex.augment_truncate_inv_f_succ
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "chain_complex" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
to_single₀_as_complex [has_zero_object V] (C : chain_complex V ℕ) (X : V) (f : C ⟶ (single₀ V).obj X) : chain_complex V ℕ
let ⟨f, w⟩ := to_single₀_equiv C X f in augment C f w
def
chain_complex.to_single₀_as_complex
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "chain_complex" ]
A chain map from a chain complex to a single object chain complex in degree zero can be reinterpreted as a chain complex. Ths is the inverse construction of `truncate_to`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
truncate [has_zero_morphisms V] : cochain_complex V ℕ ⥤ cochain_complex V ℕ
{ obj := λ C, { X := λ i, C.X (i+1), d := λ i j, C.d (i+1) (j+1), shape' := λ i j w, by { apply C.shape, simpa }, }, map := λ C D f, { f := λ i, f.f (i+1), }, }
def
cochain_complex.truncate
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "cochain_complex" ]
The truncation of a `ℕ`-indexed cochain complex, deleting the object at `0` and shifting everything else down.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
to_truncate [has_zero_object V] [has_zero_morphisms V] (C : cochain_complex V ℕ) : (single₀ V).obj (C.X 0) ⟶ truncate.obj C
(from_single₀_equiv (truncate.obj C) (C.X 0)).symm ⟨C.d 0 1, by tidy⟩
def
cochain_complex.to_truncate
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "cochain_complex" ]
There is a canonical chain map from the truncation of a cochain complex `C` to the "single object" cochain complex consisting of the truncated object `C.X 0` in degree 0. The components of this chain map are `C.d 0 1` in degree 0, and zero otherwise.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
augment (C : cochain_complex V ℕ) {X : V} (f : X ⟶ C.X 0) (w : f ≫ C.d 0 1 = 0) : cochain_complex V ℕ
{ X := λ i, match i with | 0 := X | (i+1) := C.X i end, d := λ i j, match i, j with | 0, 1 := f | (i+1), (j+1) := C.d i j | _, _ := 0 end, shape' := λ i j s, begin simp at s, rcases j with _|_|j; cases i; unfold_aux; try { simp }, { simpa using s, }, { rw [C.shape], simp only [complex_...
def
cochain_complex.augment
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "cochain_complex", "nat.one_lt_succ_succ" ]
We can "augment" a cochain complex by inserting an arbitrary object in degree zero (shifting everything else up), along with a suitable differential.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
augment_X_zero (C : cochain_complex V ℕ) {X : V} (f : X ⟶ C.X 0) (w : f ≫ C.d 0 1 = 0) : (augment C f w).X 0 = X
rfl
lemma
cochain_complex.augment_X_zero
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "cochain_complex" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
augment_X_succ (C : cochain_complex V ℕ) {X : V} (f : X ⟶ C.X 0) (w : f ≫ C.d 0 1 = 0) (i : ℕ) : (augment C f w).X (i+1) = C.X i
rfl
lemma
cochain_complex.augment_X_succ
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "cochain_complex" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
augment_d_zero_one (C : cochain_complex V ℕ) {X : V} (f : X ⟶ C.X 0) (w : f ≫ C.d 0 1 = 0) : (augment C f w).d 0 1 = f
rfl
lemma
cochain_complex.augment_d_zero_one
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "cochain_complex" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
augment_d_succ_succ (C : cochain_complex V ℕ) {X : V} (f : X ⟶ C.X 0) (w : f ≫ C.d 0 1 = 0) (i j : ℕ) : (augment C f w).d (i+1) (j+1) = C.d i j
rfl
lemma
cochain_complex.augment_d_succ_succ
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "cochain_complex" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
truncate_augment (C : cochain_complex V ℕ) {X : V} (f : X ⟶ C.X 0) (w : f ≫ C.d 0 1 = 0) : truncate.obj (augment C f w) ≅ C
{ hom := { f := λ i, 𝟙 _, }, inv := { f := λ i, by { exact 𝟙 _, }, comm' := λ i j, by { cases j; { dsimp, simp, }, }, }, hom_inv_id' := by { ext i, cases i; { dsimp, simp, }, }, inv_hom_id' := by { ext i, cases i; { dsimp, simp, }, }, }.
def
cochain_complex.truncate_augment
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "cochain_complex" ]
Truncating an augmented cochain complex is isomorphic (with components the identity) to the original complex.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
truncate_augment_hom_f (C : cochain_complex V ℕ) {X : V} (f : X ⟶ C.X 0) (w : f ≫ C.d 0 1 = 0) (i : ℕ) : (truncate_augment C f w).hom.f i = 𝟙 (C.X i)
rfl
lemma
cochain_complex.truncate_augment_hom_f
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "cochain_complex" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
truncate_augment_inv_f (C : cochain_complex V ℕ) {X : V} (f : X ⟶ C.X 0) (w : f ≫ C.d 0 1 = 0) (i : ℕ) : (truncate_augment C f w).inv.f i = 𝟙 ((truncate.obj (augment C f w)).X i)
rfl
lemma
cochain_complex.truncate_augment_inv_f
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "cochain_complex" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
cochain_complex_d_succ_succ_zero (C : cochain_complex V ℕ) (i : ℕ) : C.d 0 (i+2) = 0
by { rw C.shape, simp only [complex_shape.up_rel, zero_add], exact (nat.one_lt_succ_succ _).ne }
lemma
cochain_complex.cochain_complex_d_succ_succ_zero
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "cochain_complex", "nat.one_lt_succ_succ" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
augment_truncate (C : cochain_complex V ℕ) : augment (truncate.obj C) (C.d 0 1) (C.d_comp_d _ _ _) ≅ C
{ hom := { f := λ i, by { cases i; exact 𝟙 _, }, comm' := λ i j, by { rcases j with _|_|j; cases i; { dsimp, simp, }, }, }, inv := { f := λ i, by { cases i; exact 𝟙 _, }, comm' := λ i j, by { rcases j with _|_|j; cases i; { dsimp, simp, }, }, }, hom_inv_id' := by { ext i, cases i; { dsimp, simp, }, },...
def
cochain_complex.augment_truncate
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "cochain_complex" ]
Augmenting a truncated complex with the original object and morphism is isomorphic (with components the identity) to the original complex.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
augment_truncate_hom_f_zero (C : cochain_complex V ℕ) : (augment_truncate C).hom.f 0 = 𝟙 (C.X 0)
rfl
lemma
cochain_complex.augment_truncate_hom_f_zero
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "cochain_complex" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
augment_truncate_hom_f_succ (C : cochain_complex V ℕ) (i : ℕ) : (augment_truncate C).hom.f (i+1) = 𝟙 (C.X (i+1))
rfl
lemma
cochain_complex.augment_truncate_hom_f_succ
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "cochain_complex" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
augment_truncate_inv_f_zero (C : cochain_complex V ℕ) : (augment_truncate C).inv.f 0 = 𝟙 (C.X 0)
rfl
lemma
cochain_complex.augment_truncate_inv_f_zero
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "cochain_complex" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
augment_truncate_inv_f_succ (C : cochain_complex V ℕ) (i : ℕ) : (augment_truncate C).inv.f (i+1) = 𝟙 (C.X (i+1))
rfl
lemma
cochain_complex.augment_truncate_inv_f_succ
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "cochain_complex" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
from_single₀_as_complex [has_zero_object V] (C : cochain_complex V ℕ) (X : V) (f : (single₀ V).obj X ⟶ C) : cochain_complex V ℕ
let ⟨f, w⟩ := from_single₀_equiv C X f in augment C f w
def
cochain_complex.from_single₀_as_complex
algebra.homology
src/algebra/homology/augment.lean
[ "algebra.homology.single" ]
[ "cochain_complex" ]
A chain map from a single object cochain complex in degree zero to a cochain complex can be reinterpreted as a cochain complex. Ths is the inverse construction of `to_truncate`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83