RADIATIVE DECAY: NONPERTURBATIVE APPROACHES

Abstract

In radiative decay the coupled system, electron bound by some external potential plus radiation field, relaxes to the ground state in the long time limit. Our central issue is to prove such a behaviour on the basis of the corresponding Schrödinger equation. We argue that the spin-boson Hamiltonian is a simple, but physically still acceptable test case. We relate radiative decay to scattering theory and prove the existence of wave operators. Other approaches are reviewed and compared. Some challenging open problems are listed.