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Merge pull request #19 from GTBarkley/sayantan

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new: Added some more theorems about ses
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Sayantan Santra 2023-06-12 01:36:53 -05:00 committed by GitHub
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1 changed files with 7 additions and 2 deletions
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@ -65,7 +65,7 @@ variable (I : Ideal R)
open CategoryTheory CategoryTheory.Limits CategoryTheory.Preadditive
variable {𝒜 : Type _} [Category 𝒜] [Abelian 𝒜]
variable {A B C A': 𝒜} {f : A ⟶ B} {g : B ⟶ C}
variable {A B C : 𝒜} {f : A ⟶ B} {g : B ⟶ C} {h : LeftSplit f g} {h' : RightSplit f g}
#check ShortExact
#check ShortExact f g
@ -75,4 +75,9 @@ variable {A B C A': 𝒜} {f : A ⟶ B} {g : B ⟶ C}
#check LeftSplit f g
-- And there is a theorem that left split implies splitting
#check LeftSplit.splitting
#check LeftSplit.splitting h
-- Similar things are there for RightSplit as well
#check RightSplit.splitting
#check RightSplit.splitting h'
-- There's also a theorem about ismorphisms between short exact sequences
#check isIso_of_shortExact_of_isIso_of_isIso