English
The unit of the adjunction sends a point x ∈ X to the corresponding point of Opens X given by U ↦ [x ∈ U].
Русский
Единица сопряжения отправляет точку x ∈ X в соответствующую точку открытых подмножеств X, заданную U ↦ [x ∈ U].
LaTeX
$$localePointOfSpacePoint(X,x) : PT (Opens X) with toFun = (x ∈ ·)$$
Lean4
/-- The unit of the adjunction between locales and topological spaces, which associates with
a point `x` of the space `X` a point of the locale of opens of `X`. -/
@[simps]
def localePointOfSpacePoint (x : X) : PT (Opens X)
where
toFun := (x ∈ ·)
map_inf' _ _ := rfl
map_top' := rfl
map_sSup' S := by simp [«Prop».exists_iff]