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arXiv · nucl-th/9708037

Role of retardation in 3-D relativistic equations

A. D. Lahiff·I. R. Afnan
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Abstract

Equal-time Green's function is used to derive a three-dimensional integral equation from the Bethe-Salpeter equation. The resultant equation, in the absence of anti-particles, is identical to the use of time-ordered diagrams, and has been used within the framework of $ϕ^2σ$ coupling to study the role of energy dependence and non-locality when the two-body potential is the sum of $σ$-exchange and crossed $σ$ exchange. The results show that non-locality and energy dependence make a substantial contribution to both the on-shell and off-shell amplitudes.

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A. D. Lahiff, I. R. Afnan. 1997-08-20. Role of retardation in 3-D relativistic equations. https://doi.org/10.1103/physrevc.56.2387

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