English
A restatement of integrality for a localized map under stronger hypotheses.
Русский
Переформулировка интегральности для локализованного отображения с дополнительными предпосылками.
LaTeX
$$$\text{isIntegral_localization'}$$$
Lean4
theorem isIntegral_localization' {R S : Type*} [CommRing R] [CommRing S] {f : R →+* S} (hf : f.IsIntegral)
(M : Submonoid R) :
(map (Localization (M.map (f : R →* S))) f (M.le_comap_map : _ ≤ Submonoid.comap (f : R →* S) _) :
Localization M →+* _).IsIntegral :=
let _ := f.toAlgebra
have : Algebra.IsIntegral R S := ⟨hf⟩
have : IsLocalization (Algebra.algebraMapSubmonoid S M) (Localization (Submonoid.map (f : R →* S) M)) :=
Localization.isLocalization
isIntegral_localization