SCIENCE - Powerful new tool is quantum analog of phase space flow

Physicists have found that a new powerful tool they call 'Wigner flow' is the quantum analog of phase space flow. Wigner flow provides information for quantum dynamics similar to that gleaned from phase space trajectories in classical physics. Wigner flow can be used for the visualization of quantum dynamics. Additionally, Wigner flow helps with the abstract analysis of quantum dynamics using topological methods.

http://www.sciencedaily.com/releases/2012/12/121226080400.ht