English
Localization away from an element yields smoothness: if A is localized away from r, then A is smooth over R.
Русский
Локализация away от элемента r даёт гладкость: если A локализуется away от r, то A гладко над R.
LaTeX
$$$\operatorname{Smooth}(R,A) \text{ for } A = \operatorname{Away}_r(R)$$$
Lean4
/-- Localization at an element is smooth. -/
theorem of_isLocalization_Away (r : R) [IsLocalization.Away r A] : Smooth R A
where
formallySmooth := Algebra.FormallySmooth.of_isLocalization (Submonoid.powers r)
finitePresentation := IsLocalization.Away.finitePresentation r