English
Any nonunital star-algebra homomorphism between complex C*-algebras naturally carries a structure of a continuous linear map over the complex numbers.
Русский
Любой неконглуный звездно-алгебраический гомоморфизм между комплексными C*-алгебрами естественно наделяет структуру непрерывного линейного отображения над комплексными числами.
LaTeX
$$$\text{φ is a continuous linear map over } \mathbb{C}$$$
Lean4
/-- Non-unital star algebra homomorphisms between C⋆-algebras are continuous linear maps.
See note [lower instance priority] -/
theorem instContinuousLinearMapClassComplex : ContinuousLinearMapClass F ℂ A B :=
{ NonUnitalAlgHomClass.instLinearMapClass with
map_continuous := fun φ =>
AddMonoidHomClass.continuous_of_bound φ 1 (by simpa only [one_mul] using nnnorm_apply_le φ) }