OAI/Algebra/Finitistic/Ordinary/OrdinaryFirstDerivedRetraction.lean
8 declarations, 0 contain sorry, 0 declared as axioms
- abbrev
OAI.LittleFinitistic.BlockModule.derivedFirstComponentline 14Source documentation
The exact derived first-component functor on the whole product-ring derived category.
abbrev derivedFirstComponent := (ProductModules.firstFunctor.{u,u} L R).mapDerivedCategory - def
OAI.LittleFinitistic.BlockModule.firstComplexComponentIsoline 16 - def
OAI.LittleFinitistic.BlockModule.derivedFirstComponentFactorsline 23Source documentation
On chain representatives, the composite is the identity localization.
def derivedFirstComponentFactors : DerivedCategory.Q ⋙ derivedFirst L R ⋙ derivedFirstComponent L R ≅ (DerivedCategory.Q : CochainComplex (ModuleCat.{u} L) ℤ ⥤ _) := …Mentions: OAI.LittleFinitistic.BlockModule.derivedFirst, OAI.LittleFinitistic.BlockModule.derivedFirstComponent
- def
OAI.LittleFinitistic.BlockModule.derivedFirstRetractionline 33Source documentation
Taking the first component recovers every derived object, naturally.
def derivedFirstRetraction : derivedFirst L R ⋙ derivedFirstComponent L R ≅ 𝟭 (DerivedCategory (ModuleCat.{u} L)) := by …Mentions: OAI.LittleFinitistic.BlockModule.derivedFirst, OAI.LittleFinitistic.BlockModule.derivedFirstComponent
- def
OAI.LittleFinitistic.BlockModule.exactFirstRetractionline 43Source documentation
The same retraction for mathlib's exact derived inflation.
def exactFirstRetraction : (ProductModules.firstInflation L R).mapDerivedCategory ⋙ derivedFirstComponent L R ≅ 𝟭 (DerivedCategory (ModuleCat.{u} L)) := …Mentions: OAI.LittleFinitistic.ProductModules.firstInflation, OAI.LittleFinitistic.BlockModule.derivedFirstComponent
- instance
OAI.LittleFinitistic.BlockModule.derivedFirst_additiveline 47 - theorem
OAI.LittleFinitistic.BlockModule.derivedFirst_isZero_iffline 51Source documentation
No derived object becomes zero merely by putting it in the first block.
theorem derivedFirst_isZero_iff (Y : DerivedCategory (ModuleCat.{u} L)) : IsZero ((derivedFirst L R).obj Y) ↔ IsZero Y := by … - theorem
OAI.LittleFinitistic.BlockModule.exactFirst_isZero_iffline 59