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arXiv · hep-ph/9303321

Multiscalar amplitudes to all orders in perturbation theory

E. N. Argyres·Ronald H. P. Kleiss·Costas G. Papadopoulos
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Abstract

A method for calculating loop amplitudes at the multiboson threshold is presented, based on Feynman-diagram techniques. We explicitly calculate the one-loop amplitudes in both $ϕ^4$-symmetric and broken symmetry cases, using dimensional regularization. We argue that, to all orders in the perturbation expansion, the unitarity-violating behaviour of the tree-order amplitudes persists.

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E. N. Argyres, Ronald H. P. Kleiss, Costas G. Papadopoulos. 1993-04-01. Multiscalar amplitudes to all orders in perturbation theory. https://doi.org/10.1016/0370-2693(93)91287-w

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