Instantaneous Bethe–salpeter Equation with Exact Propagators
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چکیده
Consequent application of the instantaneous approximation to both the interaction and all propagators of the bound-state constituents allows us to forge, within the framework of the Bethe–Salpeter formalism for the description of bound states, an instantaneous form of the Bethe–Salpeter equation with exact (i.e., full) propagators of the bound-state constituents. This instantaneous equation generalizes the well-known Salpeter equation the derivation of which needs the additional assumption of free propagation of the bound-state constituents. PACS numbers: 11.10.St, 03.65.Ge, 03.65.Pm ∗ E-mail address : [email protected] † E-mail address : [email protected]
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