Subcategories of abelian categories #
Let C be an abelian category. Given P : ObjectProperty C which contains
zero, is closed under kernels, cokernels and finite products, we show that the
full subcategory defined by P is abelian.
theorem
CategoryTheory.ObjectProperty.preservesMonomorphisms_ι_of_isNormalEpiCategory
{C : Type u_1}
[Category.{v_1, u_1} C]
(P : ObjectProperty C)
[Limits.HasZeroMorphisms C]
[Limits.HasFiniteCoproducts C]
[Limits.HasKernels C]
[Limits.HasCokernels C]
[IsNormalEpiCategory C]
[Limits.HasZeroObject C]
[P.ContainsZero]
[P.IsClosedUnderKernels]
:
theorem
CategoryTheory.ObjectProperty.preservesEpimorphisms_ι_of_isNormalMonoCategory
{C : Type u_1}
[Category.{v_1, u_1} C]
(P : ObjectProperty C)
[Limits.HasZeroMorphisms C]
[Limits.HasFiniteProducts C]
[Limits.HasKernels C]
[Limits.HasCokernels C]
[IsNormalMonoCategory C]
[Limits.HasZeroObject C]
[P.ContainsZero]
[P.IsClosedUnderCokernels]
:
@[implicit_reducible]
instance
CategoryTheory.ObjectProperty.instAbelianFullSubcategoryOfContainsZeroOfIsClosedUnderKernelsOfIsClosedUnderCokernelsOfIsClosedUnderFiniteProducts
{C : Type u_1}
[Category.{v_1, u_1} C]
(P : ObjectProperty C)
[Abelian C]
[P.ContainsZero]
[P.IsClosedUnderKernels]
[P.IsClosedUnderCokernels]
[P.IsClosedUnderFiniteProducts]
: