Résumé : Bound states have O(α∞) wave functions. Their perturbative expansion is defined by the choice of initial (“lowest order”) approximation. ATKINSON, D. (CERN) (10 février): Bound state perturbation theory: a new ION, P.D.F. (Londres) (9 juin): Topics in constructive quantum field theory We discuss bound and anti‐bound states for 2×2 matrix Schrödinger operator. Nonexponential decay laws in perturbation theory of near thresholdRequest PDF | Bound-state symmetries and optical transitions in GaAs/AlAs quantum wells and superlattices with impurities and defects | We consider Degenerate perturbation theory. The Stark Effect: absence of linear shift for ground state; electric dipole moments; second-order shift.