English
An alternative noetherian_pi' instance: if M is Noetherian and ι finite, then the space of linear maps from ι → M is Noetherian.
Русский
Альтернативная версия: если M Noetherian и ι конечен, пространство линейных отображений из ι → R в M — Noetherian.
LaTeX
$$$[IsNoetherian R M] \Rightarrow IsNoetherian R (ι \to M)$$$
Lean4
instance isNoetherian_linearMap : IsNoetherian R (N →ₗ[R] M) :=
by
obtain ⟨n, f, hf⟩ := Module.Finite.exists_fin' R N
let g : (N →ₗ[R] M) →ₗ[R] (Fin n → R) →ₗ[R] M := (LinearMap.llcomp R (Fin n → R) N M).flip f
exact isNoetherian_of_injective g hf.injective_linearMapComp_right