English
If P is stable under composition for maps of topological spaces, then topologically P is stable under composition for scheme morphisms.
Русский
Если P стабильно по композиции для отображений топологических пространств, то topologically P стабильно по композиции для гомоморфизмов схем.
LaTeX
$$(topologically P).IsStableUnderComposition$$
Lean4
/-- If a property of maps of topological spaces is stable under composition, the induced
morphism property of schemes is stable under composition. -/
theorem topologically_isStableUnderComposition
(hP :
∀ {α β γ : Type u} [TopologicalSpace α] [TopologicalSpace β] [TopologicalSpace γ] (f : α → β) (g : β → γ)
(_ : P f) (_ : P g), P (g ∘ f)) :
(topologically P).IsStableUnderComposition where
comp_mem {X Y Z} f g hf
hg := by
simp only [topologically, Scheme.comp_coeBase, TopCat.coe_comp]
exact hP _ _ hf hg