This is a very very interesting and useful contribution. Thank you.

Sorry to trouble you, but the propagator is the complex amplitude x_A-->x_B, not the probability.

This is a very very interesting and useful contribution. Thank you.

Sorry to trouble you, but the propagator is the complex amplitude x_A-->x_B, not the probability.

Retired Full Professor, Tor Vergata University. Quantum Theory of Transport, Pumping, Magnetism, Superconductivity, Non linear Optics, Electron Spectroscopy,..