English
The coproduct (joint codomain) of two continuous homomorphisms to a common codomain is obtained by composing multiplication with the product map.
Русский
Копрод — это совместное отображение в общий кодомоморфизм через умножение совместно с произведением.
LaTeX
$$$f.coprod g = (mul_E).comp (f.prodMap g)$$$
Lean4
/-- Product of two continuous homomorphisms on different spaces. -/
@[to_additive (attr := simps!) prodMap /-- Product of two continuous homomorphisms on different spaces. -/
]
def prodMap (f : A →ₜ* C) (g : B →ₜ* D) : (A × B) →ₜ* (C × D) :=
⟨f.toMonoidHom.prodMap g.toMonoidHom, f.continuous_toFun.prodMap g.continuous_toFun⟩