Functoriality of bifunctor totalizations #
Fixing a left complex needs totalizations only for that complex and the right arguments.
CategoryTheory.Functor.mapBifunctorLeft and its maps in the left variable use Mathlib's
pairwise totalization and its existing maps. When all totalizations exist, this is the left
component of Mathlib's totalized bifunctor. The totalized bifunctor preserves zero morphisms.
The identity and composition calculations were previously in
TauCeti.Algebra.Homology.Bifunctor.Homotopy; that module reuses them for homotopy equivalences.
All constructions use Joël Riou's Mathlib bifunctor totalization in
Mathlib.Algebra.Homology.Bifunctor and Mathlib.Algebra.Homology.TotalComplex.
mapBifunctorMap sends the pair of identities to the identity.
mapBifunctorMap is compatible with composition in both variables simultaneously.
mapBifunctorMap is compatible with composition in both variables simultaneously.
Totalization sends a zero morphism in the left argument to zero.
Totalization sends a zero morphism in the right argument to zero.
Totalization against a fixed left complex, requiring only its own totalizations.
Instances For
The object of a fixed-left totalization is the corresponding pairwise total complex.
Maps of a fixed-left totalization use the identity on the left complex.
The fixed-left totalization preserves zero morphisms in its right argument.
A map of the chosen left complexes induces a natural map of their totalizations.
Instances For
The component of a map between fixed-left totalizations is the pairwise totalization map.
Maps between fixed-left totalizations preserve composition in the left argument.
Maps between fixed-left totalizations preserve composition in the left argument.
A zero left map induces the zero natural transformation.
The fixed-left construction agrees with the corresponding component of the full bifunctor.
The full totalized bifunctor preserves zero morphisms in its left argument.
In particular this supplies zero preservation for F.map₂CochainComplex.