The category of boolean algebras #
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This defines BoolAlg
, the category of boolean algebras.
The category of boolean algebras.
Equations
Instances for BoolAlg
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Equations
- X.boolean_algebra = X.str
Construct a bundled BoolAlg
from a boolean_algebra
.
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Turn a BoolAlg
into a BddDistLat
by forgetting its complement operation.
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Equations
- BoolAlg.has_forget_to_HeytAlg = {forget₂ := {obj := λ (X : BoolAlg), {α := ↥X, str := biheyting_algebra.to_heyting_algebra ↥X boolean_algebra.to_biheyting_algebra}, map := λ (X Y : BoolAlg) (f : X ⟶ Y), ↑((λ (this : bounded_lattice_hom ↥X ↥Y), this) f), map_id' := BoolAlg.has_forget_to_HeytAlg._proof_1, map_comp' := BoolAlg.has_forget_to_HeytAlg._proof_2}, forget_comp := BoolAlg.has_forget_to_HeytAlg._proof_3}
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theorem
BoolAlg.has_forget_to_HeytAlg_forget₂_map
(X Y : BoolAlg)
(f : X ⟶ Y) :
category_theory.has_forget₂.forget₂.map f = ↑((λ (this : bounded_lattice_hom ↥X ↥Y), this) f)
Constructs an equivalence between Boolean algebras from an order isomorphism between them.
Equations
- BoolAlg.iso.mk e = {hom := ↑e, inv := ↑(e.symm), hom_inv_id' := _, inv_hom_id' := _}
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theorem
BoolAlg.dual_map
(X Y : BoolAlg)
(ᾰ : bounded_lattice_hom ↥(X.to_BddDistLat.to_BddLat) ↥(Y.to_BddDistLat.to_BddLat)) :
order_dual
as a functor.
Equations
- BoolAlg.dual = {obj := λ (X : BoolAlg), BoolAlg.of (↥X)ᵒᵈ, map := λ (X Y : BoolAlg), ⇑bounded_lattice_hom.dual, map_id' := BoolAlg.dual._proof_1, map_comp' := BoolAlg.dual._proof_2}
The equivalence between BoolAlg
and itself induced by order_dual
both ways.
Equations
- BoolAlg.dual_equiv = category_theory.equivalence.mk BoolAlg.dual BoolAlg.dual (category_theory.nat_iso.of_components (λ (X : BoolAlg), BoolAlg.iso.mk (order_iso.dual_dual ↥X)) BoolAlg.dual_equiv._proof_1) (category_theory.nat_iso.of_components (λ (X : BoolAlg), BoolAlg.iso.mk (order_iso.dual_dual ↥X)) BoolAlg.dual_equiv._proof_2)