Contains The Angular Momentum Of Positive Energy Theorem

A proof of the positive energy theorem of general relativity isgiven . In this proof the gravitational Lagrangian is identified with that of Lau and is equivalent to the teleparallel Lagrangian , modulo a boundary term . The approach adopted in this proof uses the two-spinor method and the extended Witten identities and then combines the Brown-York and the Nester-Witten approaches . At the same time the proof is extended to the case including the contribution of angular momentum by choosing a special shift vector.