English
For the primed version, S.mapHomologyIso' F equals the trans of (hr.map F).homologyIso with F.mapIso hr.homologyIso.symm.
Русский
Для обобщённой версии S.mapHomologyIso' F = (hr.map F).homologyIso ≪≫ F.mapIso hr.homologyIso.symm.
LaTeX
$$$S.mapHomologyIso' F = (hr.map F).homologyIso \;\circ\; F.mapIso hr.homologyIso.symm$$
Lean4
@[reassoc]
theorem mapCyclesIso_hom_naturality [S₁.HasLeftHomology] [S₂.HasLeftHomology] [F.PreservesLeftHomologyOf S₁]
[F.PreservesLeftHomologyOf S₂] :
cyclesMap (F.mapShortComplex.map φ) ≫ (S₂.mapCyclesIso F).hom = (S₁.mapCyclesIso F).hom ≫ F.map (cyclesMap φ) :=
by
dsimp only [cyclesMap, mapCyclesIso, LeftHomologyData.cyclesIso, cyclesMapIso', Iso.refl]
simp only [LeftHomologyData.map_cyclesMap', Functor.mapShortComplex_obj, ← cyclesMap'_comp, comp_id, id_comp]