Development of Many-Body Perturbation Theory
نویسنده
چکیده
The development of standard MBPT for single-reference and multi-reference cases is reviewed, and its extension to the relativistic case in the form of the Dirac-Coulomb-Breit (DCB) approximation is described. The latter scheme is non-covariant, and the recent development of a fully covariant MBPT scheme is discussed. This is based upon a new scheme for quantumelectrodynamical (QED) calculations, the covariant-evolution-operator method, which is combined with standard MBPT. This scheme is fully compatible with the relativistically covariant Bethe-Salpeter equation. Some numerical results of the new scheme are given.
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