Geometric Lagrangians for massive higher-spin fields Original Research Article

Lagrangians for massive, unconstrained, higher-spin bosons and fermions are proposed. The idea is to modify the geometric, gauge invariant Lagrangians describing the corresponding massless theories by the addition of suitable quadratic polynomials. These polynomials provide generalisations of the Fierz–Pauli mass term containing all possible traces of the basic field. No auxiliary fields are needed.