Interplay of causticity and vorticality within the complex quantum Hamilton-Jacobi formalism

Within the complex quantum Hamilton-Jacobi framework, trajectory dynamics describing simple processes, such as the collinear collision of two Gaussian wave packets, become very rich and convoluted. Two types of singularities rule these dynamics: vortices and caustics. The quantum vortical dynamics associated with interference breaks off the smoothness of the causticity regime associated with free wave-packet propagation.