Hi, I am working on a problem where my goal is to predict the location of pedestrians with certain constraints. So I have equations for the pedestrian motion (using social forces model) which is based on the idea of pedestrians movements are based on the forces acting upon them. For example, if there is another pedestrian close by, the pedestrian will try to move away from him. That is pedestrian movement is based on the repulsion force acting upon him from other pedestrians. I see this problem as a similar one from repulsion forces acting on electron clouds. So my question is, let say there are two electron clouds at time k, and if you want to predict the location of the electron clouds at time (k+1), what equations are used? I am looking for the any useful links which shows how the distance and corresponding co-variance associated with the distance changes with time. My background is not from physics, so please let me know if I am stating anything wrong.