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DerivedAlgGeo.CategoryTheory.MorphismProperty.Limits

Morphism properties stable under coproducts #

Sigma.map of a family of morphisms in a class W stable under coproducts of that shape is in W: it is colimMap of the family, and MorphismProperty.colimMap is Mathlib's statement for a general colimit shape. Mathlib inlines this one-liner where it needs it; it is named here because the localization of a category along a coproduct-stable class uses it for the common denominators of families of right fractions.

Main results #

theorem CategoryTheory.MorphismProperty.sigma_map {C : Type u} [Category.{v, u} C] (W : MorphismProperty C) {ι : Type w} [Limits.HasCoproductsOfShape ι C] [W.IsStableUnderCoproductsOfShape ι] {X Y : ι → C} (s : (i : ι) → X i ⟶ Y i) (hs : ∀ (i : ι), W (s i)) :

Sigma.map of a family of morphisms in W is in W when W is stable under coproducts of that shape.