Interactions of N Goldstini in Superspace

We study field theories with N extended nonlinearly realized supersymmetries, describing the couplings of models that contain N Goldstini. We review all the known formulations of the N = 1 Goldstino theories and we generalize them to an arbitrary number N of nonlinearly realized supersymmetries. We explicitly prove the equivalence of all these extended supersymmetry breaking models containing N Goldstini and reformulate the theory with N supersymmetries in terms of standard N = 1 constrained superfields.