Chris H. Greene

 

My group concentrates on theoretical problems involving strongly-correlated few-body quantum systems in various regimes, including ultracold atomic gases, electron-molecule collisions, and laser-molecule interactions. The description of quantum systems with a modest number of strongly-interacting degrees of freedom is highly challenging, even though extensive progress has been made in recent decades. When perturbation theories can be utilized, there is a standard toolkit that is readily applied, but when collective effects are strong, as they often are, we find it advantageous to explore alternative formulations using unconventional coordinate systems such as hyperspherical coordinates. We often utilize adiabatic formulations in one or more coordinates, in order to gain physical insight and map the interaction physics. In many cases this can be applied quantitatively to make predictions or to understand previously uninterpreted phenomena.