Abstract:
Scattering amplitudes and Cross Sections are most prominent observable in the context of collider experiments. Almost everything we know experimentally about gauge theory is based on scattering processes with asymptotic, on-shell and partially o↵-shell (Form factor) states, evaluated in perturbation theory. So far the Standard Model (SM) of Particle Physics is the most successful theory to understand the quantum nature and dynamics of the elementary constituents of matter excluding Gravity. The quest for searching the new physics beyond SM has intensified after the discovery of Higgs Boson at Large Hadron Collider (LHC)in CERN, Geneva. For discovering the new physics , we will need to understand the SM with unprecedented accuracy. Till date the only reliable way to predict SM cross sections in general lies under the framework of perturbative Quantum Field Theory (QFT). The matrix elements (M) as well as the observable in perturbative
QFT are expanded in powers of coupling constants, c, present in the theory which is needed to be small enough in order to have a asymptotic series expansion :
