scattering amplitudes in quantum field theories (the class of theories that physicists use to describe subatomic particles) have been calculated using what are known as Feynman Diagrams.

And the second problem is that when we quantify the ' scattering ... When Feynman presented Feynman diagrams, his colleagues were confused because he did not know how to use Feynman diagrams ...

Generations of physicists have spent much of their lives using Richard Feynman's famous diagrams to calculate ... Feynman's formulae for many kinds of scattering processes, and then testing ...