OAI/Algebra/Finitistic/Ordinary/OrdinaryProductSecondDimension.lean
3 declarations, 0 contain sorry, 0 declared as axioms
- def
OAI.LittleFinitistic.ProductModules.swapInflationEquivline 15Source 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
- theorem
OAI.LittleFinitistic.ProductModules.secondInflation_dimensionLEline 27 - theorem
OAI.LittleFinitistic.ProductModules.product_module_boundline 34Source 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 …