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arXiv · 1007.2742

The MHV Lagrangian for a spontaneously broken gauge theory

Sebastian Buchta·Stefan Weinzierl
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Abstract

Starting from the standard Lagrangian for a SU(2) x U(1) gauge theory plus a Higgs field we derive the corresponding "maximal helicity violating" (MHV) Lagrangian. From this MHV Lagrangian one deduces simple diagrammatic rules for the calculation of multi-particle scattering amplitudes. We arrive at the MHV Lagrangian by a canonical change of the field variables in the light-cone gauge. We comment on the modifications which occur in a spontaneously broken gauge theory as compared to a pure (unbroken) Yang-Mills theory.

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Sebastian Buchta, Stefan Weinzierl. 2010-07-16. The MHV Lagrangian for a spontaneously broken gauge theory. https://doi.org/10.1007/jhep09(2010)071

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