Transverse symmetry and spin-3/2 fields

Abstract

We study the possible covariant Lagrangians that describe the propagation of pure spin-3/2 particles. We show that, apart from the well-known Rarita–Schwinger Lagrangian, there is another possibility where the field is described by a γ-traceless combination and that both Lagrangians yield the same physical predictions for the interaction of conserved sources. We also prove that for the case when the spin-2 field is described by a traceless field, there is no possible spin-3/2 action that makes the system supersymmetric. Nevertheless, the interaction between this field and the spin-3/2 field may be possible.