OAI/Algebra/Finitistic/Ordinary/OrdinaryProductSecondDimension.lean

GitHub source file

3 declarations, 0 contain sorry, 0 declared as axioms

  1. def OAI.LittleFinitistic.ProductModules.swapInflationEquiv line 15

    Source documentation

    Swapping product factors identifies the two actual inflation constructions.

    def swapInflationEquiv (P : ModuleCat.{v} R) :
        (firstInflation R L).obj P ≃ₛₗ[RingHomClass.toRingHom (RingEquiv.prodComm : R × L ≃+* L × R)]
          (secondInflation L R).obj P where
    …

    Mentions: OAI.LittleFinitistic.ProductModules.firstInflation, OAI.LittleFinitistic.ProductModules.secondInflation

  2. theorem OAI.LittleFinitistic.ProductModules.secondInflation_dimensionLE line 27
  3. theorem OAI.LittleFinitistic.ProductModules.product_module_bound line 34

    Source documentation

    Each module over the product has the same finite bound as its two factors.

    theorem product_module_bound (n : ℕ)
        (hL : ∀ M : ModuleCat.{v} L, projectiveDimension M ≤ (n : ℕ))
        (hR : ∀ M : ModuleCat.{v} R, projectiveDimension M ≤ (n : ℕ))
        (M : ModuleCat.{v} (L × R)) : projectiveDimension M ≤ (n : ℕ) := by
    …