Sharif Digital Repository

Studing the Scattering Amplitudes has a crucial importance in Quantum Field Theory; and nowadays; there have been many progress in computing these observables: Scattering amplitudes respect the symmetries of a theory: However; it is possible for them to have more symmetries than ones can be seen from the lagrangian of the theory: On the other hand; Feynman diagrams which manifest the locality and unitarity of the theory are not applicable in these kind of theories; since for computing the easiest scattering amplitudes thousends of these diagrams must be computed: In this work; we are going to see using BCFW recursion relation and onshell diagrams how it is easy to compute the scattering...