English
There is a canonical isomorphism between the biproduct G ⊞ H and the cartesian product G × H in AddCommGrpCat.
Русский
Существует каноническое изоморфизм между бипродуктом G ⊞ H и декартовым произведением G × H в AddCommGrpCat.
LaTeX
$$(G ⊞ H) ≅ AddCommGrpCat.of (G × H)$$
Lean4
/-- We verify that the biproduct in `AddCommGrpCat` is isomorphic to
the Cartesian product of the underlying types:
-/
noncomputable def biprodIsoProd (G H : AddCommGrpCat.{u}) : (G ⊞ H : AddCommGrpCat) ≅ AddCommGrpCat.of (G × H) :=
IsLimit.conePointUniqueUpToIso (BinaryBiproduct.isLimit G H) (binaryProductLimitCone G H).isLimit