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Breit-Wigner formalism for non-Abelian theories

Joannis Papavassiliou
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Abstract

The consistent description of resonant transition amplitudes within the framework of perturbative field theories necessitates the definition and resummation of off-shell Green's functions, which must respect several crucial physical requirements. In particular, the generalization of the usual Breit-Wigner formalism in a non-Abelian context constitutes a highly non-trivial problem, related to the fact that the conventionally defined Green's functions are unphysical. We briefly review the main field-theoretical difficulties arising when attempting to use such Green's functions outside the confines of a fixed order perturbative calculation, and explain how this task has been successfully accomplished in the framework of the pinch technique.

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Joannis Papavassiliou. 2001-02-13. Breit-Wigner formalism for non-Abelian theories. https://doi.org/10.1088/0954-3899%2F29%2F1%2F316

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