Spectral Analysis of an Effective Hamiltonian in Nonrelativistic Quantum Electrodynamics

Abstract

We investigate spectral properties of an effective Hamiltonian which is obtained as a scaling limit of the Pauli-Fierz model in nonrelativistic quantum electrodynamics. The Lamb shift of a hydrogen-like atom is derived as the lowest order approximation (in the fine structure constant) of an energy level shift of the effective Hamiltonian. © 2010 Springer Basel AG.