English
The Pi-product of two nonunital star-algebra homomorphisms yields a nonunital star-algebra homomorphism into the product space.
Русский
Произведение по пи двух ненаправленных звездно-алгебра-гомоморфизмов даёт гомоморфизм в произведение.
LaTeX
$$$f: A \to× COORD$$$
Lean4
/-- The `Pi.prod` of two morphisms is a morphism. -/
@[simps!]
def prod (f : A →⋆ₙₐ[R] B) (g : A →⋆ₙₐ[R] C) : A →⋆ₙₐ[R] B × C :=
{ f.toNonUnitalAlgHom.prod g.toNonUnitalAlgHom with map_star' := fun x => by simp [map_star, Prod.star_def] }