Space-adiabatic perturbation theory in quantum dynamics

A systematic approximation scheme was developed for the time-dependent Schrödinger equation with a space-adiabatic Hamiltonian. The kinematics was separated from dynamics for a particular isolated energy band. The kinematics was defined by a subspace of the full Hilbert space. The Born-Oppenheimer theory to second order was discussed and the nonperturbative definition of the g factor of the electron within nonrelativistic quantum electrodynamics was derived.