theorem crisis_zeroes_multiplier (e : NSectorEconomy N) (n : Fin N)
(hT : sectorCriticalFriction e n ≤ e.T n) :
effectiveSectorMultiplier e n = 0 := by
simp only [effectiveSectorMultiplier]
rw [weakest_sector_crisis e n hT, zero_mul]Multiplier-Cycle Duality in a Multi-Sector Economy