OAI/Algebra/Finitistic/Rectification/VertexHomology.lean

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3 declarations, 0 contain sorry, 0 declared as axioms

  1. theorem OAI.LittleFinitistic.VertexHomology.preservesHomology line 18

    Source documentation

    Actual vertex projection preserves homology, because it preserves the short exact sequences already proved in VertexFunctor.

    theorem preservesHomology : (VertexFunctor.functor β e hc).PreservesHomology :=
    …

    Mentions: OAI.LittleFinitistic.VertexFunctor.functor

  2. def OAI.LittleFinitistic.VertexHomology.iso line 23

    Source documentation

    Homology of the actual vertex complex is the actual vertex of module homology.

    def iso (X : CochainComplex (ModuleCat.{u} A) ℤ) (n : ℤ) :
        (((VertexFunctor.functor β e hc).mapHomologicalComplex (.up ℤ)).obj X).homology n ≅
          (VertexFunctor.functor β e hc).obj (X.homology n) := by
    …

    Mentions: OAI.LittleFinitistic.VertexFunctor.functor

  3. theorem OAI.LittleFinitistic.VertexHomology.natural line 31

    Source documentation

    This comparison respects every natural transformation of the vertex functors, so it retains the algebra arrow actions as well as the vertex vector spaces.

    theorem natural (e' : A) (he' : e'*e'=e') (hc' : ∀ b, e'*β b=β b*e')
        (τ : VertexFunctor.functor β e hc ⟶ VertexFunctor.functor β e' hc')
        (X : CochainComplex (ModuleCat.{u} A) ℤ) (n : ℤ) :
        homologyMap ((NatTrans.mapHomologicalComplex τ (.up ℤ)).app X) n ≫
          (iso β e' he' hc' X n).hom =
        (iso β e he hc X n).hom ≫ τ.app (X.homology n) := by
    …

    Mentions: OAI.LittleFinitistic.VertexFunctor.functor, OAI.LittleFinitistic.VertexHomology.iso