Field Theoretic Approach to Atomic Helium

摘要: Publisher Summary The simplest few-body problem is the hydrogen atom for which Green's function method gives Schrodinger equation, and thus trivial. helium isoelectronic series nontrivial problem, discussed in this chapter. investigation illustrates application of rather formal field theoretic methods diagrams to a simple system, familiar. singlet triplet states behave like boson fermion systems respectively, since spin will be separated out from beginning. functions are taken with respect ground state one-particle poles occur two particle no-particle system. chapter deals many-body atomic order illustrate technique. Hamiltonian vectors written second quantization. its spectral representation introduced. single-particle equation motion obtained. Further, two-particle discussed. perturbation expansion obtained state. factorization investigated. A comparison Hartree-Fock theory drawn. factorized approximate propagator