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arXiv · hep-th/9910024

Multi-channel Bethe-Salpeter equation

J. Boguszynski·H. D. Dahmen·R. Kretschmer·L. Lukaszuk
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Abstract

A general form of multi-channel Bethe-Salpeter equation is considered. In contradistinction to the hitherto applied approaches, our coupled system of equations leads to the simultaneous solutions for all relativistic four-point Green functions (elastic and inelastic) appearing in a given theory. A set of relations which may be helpful in approximate treatments is given. An example of extracting useful information from the equations is discussed: we consider the most general trilinear coupling of N different scalar fields and obtain - in the ladder approximation - closed expressions for the Regge trajectories and their couplings to different channels in the vicinity of l = -1. Sum rules and an example containing non-obvious symmetry are discussed.

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J. Boguszynski, H. D. Dahmen, R. Kretschmer, L. Lukaszuk. 2000-12-14. Multi-channel Bethe-Salpeter equation. https://doi.org/10.1088/1126-6708%2F2000%2F11%2F002

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