General properties of the decay amplitudes for massless particles
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 YangMills bosons vanish to all orders and the decay probability of gravitons vanishes to oneloop 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 selfcoupling without derivatives and with a coupling constant of positive mass dimension.
 Publication:

Nuclear Physics B
 Pub Date:
 February 1996
 DOI:
 10.1016/05503213(96)00346X
 arXiv:
 arXiv:hepth/9508018
 Bibcode:
 1996NuPhB.477..623F
 Keywords:

 High Energy Physics  Theory
 EPrint:
 Latex file, 32 pages, to appear in Nucl. Phys. B. Improved presentation, some additional results and references, typos corrected