Covariantly Quantized Spinning Particle and Its Possible Connection to Non-commutative Space-time

Covariant quantization of the Nambu-Goto spinning particle in 2+1-dimensions is studied. The model is relevant in the context of recent activities in non-commutative space-time. From a technical point of view also covariant quantization of the model poses an interesting problem: the set of second class constraints (in the Dirac classification scheme) is reducible. The reducibility problem is analyzed from two contrasting approaches: (i) the auxiliary variable method [8] and (ii) the projection operator method [9]. Finally in the former scheme, a Batalin-Tyutin quantization has been done. This induces a mapping between the non-commutative and the ordinary space-time. BRST quantization programme in the latter scheme has also been discussed.