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algebra.​category.​Algebra.​basic

algebra.​category.​Algebra.​basic

structure Algebra (R : Type u) [comm_ring R] :
Type (u+1)

The category of R-modules and their morphisms.

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def Algebra.​of (R : Type u) [comm_ring R] (X : Type u) [ring X] [algebra R X] :

The object in the category of R-algebras associated to a type equipped with the appropriate typeclasses.

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def Algebra.​inhabited (R : Type u) [comm_ring R] :

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theorem Algebra.​of_apply (R : Type u) [comm_ring R] (X : Type u) [ring X] [algebra R X] :

def Algebra.​of_self_iso {R : Type u} [comm_ring R] (M : Algebra R) :

Forgetting to the underlying type and then building the bundled object returns the original algebra.

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theorem Algebra.​of_self_iso_hom {R : Type u} [comm_ring R] (M : Algebra R) :

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theorem Algebra.​of_self_iso_inv {R : Type u} [comm_ring R] (M : Algebra R) :

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theorem Algebra.​id_apply {R : Type u} [comm_ring R] {M : Module R} (m : ↥M) :
⇑(𝟙 M) m = m

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theorem Algebra.​coe_comp {R : Type u} [comm_ring R] {M N U : Module R} (f : M ⟶ N) (g : N ⟶ U) :
⇑(f ≫ g) = ⇑g ∘ ⇑f

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theorem alg_equiv.​to_Algebra_iso_hom {R : Type u} [comm_ring R] {X₁ X₂ : Type u} {g₁ : ring X₁} {g₂ : ring X₂} {m₁ : algebra R X₁} {m₂ : algebra R X₂} (e : X₁ ≃ₐ[R] X₂) :

def alg_equiv.​to_Algebra_iso {R : Type u} [comm_ring R] {X₁ X₂ : Type u} {g₁ : ring X₁} {g₂ : ring X₂} {m₁ : algebra R X₁} {m₂ : algebra R X₂} :
(X₁ ≃ₐ[R] X₂) → (Algebra.of R X₁ ≅ Algebra.of R X₂)

Build an isomorphism in the category Algebra R from a alg_equiv between algebras.

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theorem alg_equiv.​to_Algebra_iso_inv {R : Type u} [comm_ring R] {X₁ X₂ : Type u} {g₁ : ring X₁} {g₂ : ring X₂} {m₁ : algebra R X₁} {m₂ : algebra R X₂} (e : X₁ ≃ₐ[R] X₂) :

def category_theory.​iso.​to_alg_equiv {R : Type u} [comm_ring R] {X Y : Algebra R} :
(X ≅ Y) → (↥X ≃ₐ[R] ↥Y)

Build a alg_equiv from an isomorphism in the category Algebra R.

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theorem category_theory.​iso.​to_alg_equiv_inv_fun {R : Type u} [comm_ring R] {X Y : Algebra R} (i : X ≅ Y) (a : ↥Y) :

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theorem category_theory.​iso.​to_alg_equiv_to_fun {R : Type u} [comm_ring R] {X Y : Algebra R} (i : X ≅ Y) (a : ↥X) :

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theorem alg_equiv_iso_Algebra_iso_hom {R : Type u} [comm_ring R] {X Y : Type u} [ring X] [ring Y] [algebra R X] [algebra R Y] (e : X ≃ₐ[R] Y) :

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theorem alg_equiv_iso_Algebra_iso_inv {R : Type u} [comm_ring R] {X Y : Type u} [ring X] [ring Y] [algebra R X] [algebra R Y] (i : Algebra.of R X ≅ Algebra.of R Y) :

def alg_equiv_iso_Algebra_iso {R : Type u} [comm_ring R] {X Y : Type u} [ring X] [ring Y] [algebra R X] [algebra R Y] :

algebra equivalences between algebrass are the same as (isomorphic to) isomorphisms in Algebra

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def Algebra.​has_coe {R : Type u} [comm_ring R] (X : Type u) [ring X] [algebra R X] :

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