Finite BRST transformation and constrained systems

► Batalin-Fradkin-Tyutin (BFT) formulation converts second class theory to first class. ► We develop a different formulation known as FFBRST/FF-anti-BRST formulations. ► Such transformation is developed by making usual parameter finite and field dependent. ► We relate first class theory to second class using FFBRST/FF-anti-BRST formulation.