“…Putkaradze et al 16 studied experimentally the velocity profile and the related instabilities and bifurcation of the flows through diverging channels and concluded, in a heuristic manner, that the solutions revealed absolute instability. Swaminathan et al 3 were the first to study the spatially developing global linear stability analysis problem to reveal that the disturbance modes are not the wave-like perturbations postulated in earlier work 5,6,2,1,8,7,9,11,13,15,16,12 as assumed by local parallel or weakly non-parallel analyses and question the relation between the Re cr and the α, but rather are large-scale structures filling the entire computational domain.…”