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Theorems · Inductive type · category theory

CategoryTheory.Functor.EssSurj

{C : Type u₁} →
  {D : Type u₂} →
    [inst : CategoryTheory.Category.{v₁, u₁} C] →
      [inst_1 : CategoryTheory.Category.{v₂, u₂} D] → CategoryTheory.Functor C D → Prop

A functor F : C ⥤ D is essentially surjective if every object of D is in the essential image of F. In other words, for every Y : D, there is some X : C with F.obj X ≅ Y.

Defined in
Mathlib.CategoryTheory.EssentialImage
Cited by
88 results in Mathlib
Foundations
Depth 2 from the axioms · uses no axioms
Assumes
CategoryTheory.CategoryCategoryTheory.Category

Around this declaration

Dashed lines are statement dependencies; solid lines are citations in proofs.

CategoryTheory.Functor.objObjPreimageIso · cited by 54Functor.objObjPreimageIsoCategoryTheory.Functor.objPreimage · cited by 49Functor.objPreimageCategoryTheory.Localization.essSurj · cited by 16Localization.essSurjCategoryTheory.Functor.EssSurj.mem_essImage · cited by 14EssSurj.mem_essImageCategoryTheory.Localization.natTrans_ext · cited by 7Localization.natTrans_extCategoryTheory.Localization.essSurj_mapArrow · cited by 4Localization.essSurj_mapA…CategoryTheory.Functor.essImage_comp_of_essSurj · cited by 3Functor.essImage_comp_of_…CategoryTheory.ObjectProperty.SerreClassLocalization.preservesCokernel · cited by 3SerreClassLocalization.pr…CategoryTheory.ObjectProperty.SerreClassLocalization.preservesKernel · cited by 3SerreClassLocalization.pr…CategoryTheory.LocalizerMorphism.isLeftDerivabilityStructure_of_isLocalizedEquivalence · cited by 3LocalizerMorphism.isLeftD…CategoryTheory.TwoSquare.GuitartExact.of_hComp · cited by 3GuitartExact.of_hCompCategoryTheory.Localization.functor_additive_iff · cited by 2Localization.functor_addi…CategoryTheory.LocalizerMorphism.essSurj_of_hasRightResolutions · cited by 2LocalizerMorphism.essSurj…CategoryTheory.LocalizerMorphism.hasLeftResolutions_of_iso_of_essSurj · cited by 2LocalizerMorphism.hasLeft…CategoryTheory.LocalizerMorphism.hasRightResolutions_of_iso_of_essSurj · cited by 2LocalizerMorphism.hasRigh…CategoryTheory.Category · cited by 32673CategoryTheory.CategoryCategoryTheory.Functor · cited by 16252CategoryTheory.FunctorFunctor.EssSurjCITED BYCITES

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