OAI/Algebra/Finitistic/Localization/KaroubiEvaluation.lean

GitHub source file

6 declarations, 0 contain sorry, 0 declared as axioms

  1. def OAI.LittleFinitistic.QuadraticEncoding.splitKaroubiIso line 13

    Source documentation

    An actual splitting realizes the corresponding formal Karoubi object.

    def splitKaroubiIso {A I : C} (p : A ⟶ A) (hp : p ≫ p = p)
        (π : A ⟶ I) (ι : I ⟶ A) (hπι : π ≫ ι = p) (hιπ : ι ≫ π = 𝟙 I) :
        (⟨A,p,hp⟩ : Karoubi C) ≅ (toKaroubi C).obj I where
    …
  2. def OAI.LittleFinitistic.QuadraticEncoding.transportKaroubiIso line 22

    Source documentation

    An isomorphism commuting with idempotents identifies their formal summands.

    def transportKaroubiIso (A B : Karoubi C) (e : A.X ≅ B.X)
        (h : A.p ≫ e.hom = e.hom ≫ B.p) : A ≅ B where
    …

    Mentions: OAI.LittleFinitistic.QuadraticEncoding.B

  3. def OAI.LittleFinitistic.QuadraticEncoding.karoubiEvaluation line 43
  4. def OAI.LittleFinitistic.QuadraticEncoding.quotientSummand line 47
  5. def OAI.LittleFinitistic.QuadraticEncoding.stalkSummand line 52
  6. def OAI.LittleFinitistic.QuadraticEncoding.evaluatedSummandIso line 60

    Source documentation

    The evaluated formal summand has precisely the idempotent induced by r on Y.

    def evaluatedSummandIso (r : PresentedAlgebra P) (hr : r*r=r) :
        (karoubiEvaluation X).obj (quotientSummand r hr) ≅ stalkSummand X r hr :=
    …

    Mentions: OAI.LittleFinitistic.QuadraticEncoding.PresentedAlgebra, OAI.LittleFinitistic.QuadraticEncoding.karoubiEvaluation, OAI.LittleFinitistic.QuadraticEncoding.quotientSummand, OAI.LittleFinitistic.QuadraticEncoding.stalkSummand