Homomorphisms of R-coalgebras #
This file defines bundled homomorphisms of R-coalgebras. We largely mimic
Mathlib/Algebra/Algebra/Hom.lean.
Main definitions #
CoalgHom R A B: the type ofR-coalgebra morphisms fromAtoB.Coalgebra.counitCoalgHom R A : A →ₗc[R] R: the counit of a coalgebra as a coalgebra homomorphism.
Notations #
A →ₗc[R] B:R-coalgebra homomorphism fromAtoB.
Given R-modules A, B with comultiplication maps Δ_A, Δ_B and counit maps
ε_A, ε_B, an R-coalgebra homomorphism A →ₗc[R] B is an R-linear map f such that
ε_B ∘ f = ε_A and (f ⊗ f) ∘ Δ_A = Δ_B ∘ f.
- toFun : A → B
- counit_comp : Coalgebra.counit ∘ₗ self.toLinearMap = Coalgebra.counit
- map_comp_comul : TensorProduct.map self.toLinearMap self.toLinearMap ∘ₗ Coalgebra.comul = Coalgebra.comul ∘ₗ self.toLinearMap
Instances For
Given R-modules A, B with comultiplication maps Δ_A, Δ_B and counit maps
ε_A, ε_B, an R-coalgebra homomorphism A →ₗc[R] B is an R-linear map f such that
ε_B ∘ f = ε_A and (f ⊗ f) ∘ Δ_A = Δ_B ∘ f.
Equations
- «term_→ₗc_» = Lean.ParserDescr.trailingNode `«term_→ₗc_» 25 26 (Lean.ParserDescr.binary `andthen (Lean.ParserDescr.symbol " →ₗc ") (Lean.ParserDescr.cat `term 25))
Instances For
Given R-modules A, B with comultiplication maps Δ_A, Δ_B and counit maps
ε_A, ε_B, an R-coalgebra homomorphism A →ₗc[R] B is an R-linear map f such that
ε_B ∘ f = ε_A and (f ⊗ f) ∘ Δ_A = Δ_B ∘ f.
Equations
- One or more equations did not get rendered due to their size.
Instances For
CoalgHomClass F R A B asserts F is a type of bundled coalgebra homomorphisms
from A to B.
- counit_comp (f : F) : Coalgebra.counit ∘ₗ ↑f = Coalgebra.counit
- map_comp_comul (f : F) : TensorProduct.map ↑f ↑f ∘ₗ Coalgebra.comul = Coalgebra.comul ∘ₗ ↑f
Instances
Turn an element of a type F satisfying CoalgHomClass F R A B into an actual
CoalgHom. This is declared as the default coercion from F to A →ₗc[R] B.
Equations
- ↑f = { toFun := ⇑f, map_add' := ⋯, map_smul' := ⋯, counit_comp := ⋯, map_comp_comul := ⋯ }
Instances For
Equations
- CoalgHomClass.instCoeToCoalgHom = { coe := CoalgHomClass.toCoalgHom }
See Note [custom simps projection]
Equations
- CoalgHom.Simps.apply f = ⇑f
Instances For
Copy of a CoalgHom with a new toFun equal to the old one. Useful to fix definitional
equalities.
Equations
- f.copy f' h = { toLinearMap := (↑f).copy f' h, counit_comp := ⋯, map_comp_comul := ⋯ }
Instances For
Identity map as a CoalgHom.
Equations
- CoalgHom.id R A = { toLinearMap := LinearMap.id, counit_comp := ⋯, map_comp_comul := ⋯ }
Instances For
Composition of coalgebra homomorphisms.
Equations
- φ₁.comp φ₂ = { toLinearMap := ↑φ₁ ∘ₗ ↑φ₂, counit_comp := ⋯, map_comp_comul := ⋯ }
Instances For
The counit of a coalgebra as a CoalgHom.
Equations
- Coalgebra.counitCoalgHom R A = { toLinearMap := Coalgebra.counit, counit_comp := ⋯, map_comp_comul := ⋯ }
Instances For
If φ : A → B is a coalgebra map and a = ∑ xᵢ ⊗ yᵢ, then φ a = ∑ φ xᵢ ⊗ φ yᵢ
Equations
- repr.induced φ = Coalgebra.Repr.mk repr.index (⇑φ ∘ repr.left) (⇑φ ∘ repr.right) ⋯