The two-fermion vector potential of constraint theory from Feynman diagrams
نویسنده
چکیده
The relativistic fermion-antifermion bound state vector potential of constraint theory is calculated, in perturbation theory, by means of the Lippmann−Schwinger type equation that relates it to the scattering amplitude. Leading contributions of n-photon exchange diagrams are calculated in an approximation scheme that adapts eikonal approximation to the bound state problem. They produce terms proportional, in three-dimensional x-space, to (α/r). The series of leading contributions is summed. PACS numbers : 03.65.Pm, 11.10.St, 12.20.Ds. ∗Unité de Recherche des Universités Paris 11 et Paris 6 associée au CNRS.
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تاریخ انتشار 1995