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arXiv · hep-th/9508018

General properties of the decay amplitudes for massless particles

G. Fiore·G. Modanese
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Abstract

We derive the kinematical constraints which characterize the decay of any massless particle in flat spacetime. We show that in perturbation theory the decay probabilities of photons and Yang-Mills bosons vanish to all orders; the decay probability of the graviton vanishes to one-loop order for graviton loops and to all orders for matter loops. A general power counting argument indicates in which conditions a decay of a massless particle could be possible: the lagrangian should contain a self-coupling without derivatives and with a coupling constant of positive mass dimension.

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G. Fiore, G. Modanese. 1996-06-26. General properties of the decay amplitudes for massless particles. https://doi.org/10.1016/0550-3213(96)00346-x

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