[net.physics] Feynman diagram question -- for experts

matt@oddjob.UChicago.UUCP (Matt Crawford) (08/22/84)

Is there a way I can just look at a term in the interaction lagrangian and
know for certain whether the corresponding vertex should have a +i or a -i
multiplying the coupling?  Assume, of course, that I know the spins of all
the fields, and the signature of the metric being used.
___________________________________________________________
Matt		University	ARPA: crawford@anl-mcs.arpa
Crawford	of Chicago	UUCP: ihnp4!oddjob!matt