Bhatnagar, Shashank (PhD)Mekonnen, Teferi2018-07-042023-11-092018-07-042023-11-092010-06http://10.90.10.223:4000/handle/123456789/6385In this thesis we rst give a Lagrangian formulation of the gauge theories QED and QCD. We derive the Feynman rules for QCD . AS an application of the rule, we rst present the calculation of cross section for the process q+ q ! g+g as a mathematical preliminary. We then derive the 2-particle Bethe-Salpeter equation. Then we evaluate the cross section for the production of double heavy quarkonium production in high energy electron-positron collisions at the center of mass energy p s 10.6 GeV. The cross section for the process of e+e􀀀 ! J= + c at the stated energy has been calculated by applying the two-particle Bethe-Salpeter wave equation. We have used the heavy quark limit and calculated the cross section for the lowest order diagram. The results are in broad agreement with the Belle's data available recentlyenElectron-Positron CollisionsThesis