In calculations for a particular process every possible one of these is written down so as to include its contribution to the total probability for the process to occur.
In calculations for a particular process every possible one of these is written down so as to include its contribution to the total probability for the process to occur. The simplest ones involve two vertices, which are always at the intersection of three lines. They involve a space dimension and a time dimension, with straight lines representing fermions and wavy lines bosons, with antiparticles represented as moving backward in time. FTP, what are these graphs used to represent the interactions of elementary particles named for the American who developed them?
In calculations for a particular process every possible one of these is written down so as to include its contribution to the total probability for the process to occur.
Feynman diagrams