English
For R-algebras A,B and f,g: A →ₐ[R] B, the inclusion map from the equalizer in CommRingCat.Under coincides with the underlying map of the equalizer AlgHom between f and g.
Русский
Для R-алгебр A,B и гомоморфизмов f,g: A →ₐ[R] B, топор-1 равнозначное включение в Under совпадает с отображением из равновесия AlgHom f g на уровне underlying-монта.
LaTeX
$$$ (\mathrm{Under.equalizerFork'} f g).\iota = (\mathrm{AlgHom.equalizer} f g).\val.toUnder $$$
Lean4
@[simp]
theorem equalizerFork'_ι {A B : Type u} [CommRing A] [CommRing B] [Algebra R A] [Algebra R B] (f g : A →ₐ[R] B) :
(Under.equalizerFork' f g).ι = (AlgHom.equalizer f g).val.toUnder :=
rfl