Nonlinear Realizations of Supersymmetry and Other Symmetries

Simultaneous nonlinear realizations of spontaneously broken supersym-metry in conjunction with other spontaneous and/or explicitly broken symmetries including R symmetry, global chiral symmetry, dilatations and the superconformal symmetries is reviewed. If supersymmetry (SUSY) is to be realized in nature, then it must be as a broken symmetry. Moreover, in order to be able to consistently gauge the symmetry thus producing a supergravity, the breaking must be spontaneous. Consequently, its dynamics necessarily includes a Nambu-Goldstone fermion, the Goldstino. An extremely useful, model independent, way of en-sapsulating the dynamical constraints mandated by the spontaneous symmetry breakdown is through the use of effective Lagrangians based on nonlinear realizations[1]-[2].