caa a22 4500 605488614 CHVBK 20210128100456.0 cr unu---uuuuu 210128e20151101xx s 000 0 eng 10.1007/s00214-015-1707-6 doi (NATIONALLICENCE)springer-10.1007/s00214-015-1707-6 Combination of many-body perturbation theory and quantum electrodynamics [Elektronische Daten] [Ingvar Lindgren, Johan Holmberg, Sten Salomonson] A procedure for energy-dependent perturbation expansion has been developed, based upon the covariant evolution operator method. This makes it possible to treat energy-dependent perturbations very much like the energy-independent ones in standard many-body perturbation theory. This has been applied to the non-radiative QED perturbations (retardation and virtual electron-positron pairs) as well as the radiative ones (electron self-energy, vacuum polarization and vertex correction). The combination of QED and electron correlation, beyond two-photon exchange, has been evaluated, using the Coulomb gauge. It turned out that in that gauge the extremely time-consuming model-space contributions of the self-energy and vertex corrections do not have to be evaluated in full. In the Feynman gauge no sensible results could be obtained in this way, as is demonstrated by the numerical results. Springer-Verlag Berlin Heidelberg, 2015 Perturbation theory nationallicence Quantum electrodynamics nationallicence Electron correlation nationallicence Electron self-energy nationallicence Green's operator nationallicence Covariant evolution operator nationallicence Lindgren Ingvar Department of Physics, University of Gothenburg, Gothenburg, Sweden aut Holmberg Johan Physikalisches Institut, Universität Heidelberg, Heidelberg, Germany aut Salomonson Sten Department of Physics, University of Gothenburg, Gothenburg, Sweden aut Theoretical Chemistry Accounts Springer Berlin Heidelberg 134/11(2015-11-01), 1-5 1432-881X 134:11<1 2015 134 214 https://doi.org/10.1007/s00214-015-1707-6 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00214-015-1707-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Lindgren Ingvar Department of Physics, University of Gothenburg, Gothenburg, Sweden aut NATIONALLICENCE 700 1- Holmberg Johan Physikalisches Institut, Universität Heidelberg, Heidelberg, Germany aut NATIONALLICENCE 700 1- Salomonson Sten Department of Physics, University of Gothenburg, Gothenburg, Sweden aut NATIONALLICENCE 773 0- Theoretical Chemistry Accounts Springer Berlin Heidelberg 134/11(2015-11-01), 1-5 1432-881X 134:11<1 2015 134 214