GAUGE-COVARIANT WESS-ZUMINO ACTIONS FOR SUPER p-BRANES IN SUPERSPACE

Abstract

We present a general method of constructing manifestly world-volume supersymmetric actions of super p-branes, starting from some higher-dimensional field theories in which the partial breaking of global supersymmetry (PBGS) comes about. Our approach is based upon a substitution of the superspace coordinates which relates linear and nonlinear realizations of PBGS. As instructive examples we consider the massive d=2 superparticle (p=0) and d=4 superstring (p=1). The relevant world-line and world-sheet superfied actions naturally appear as a long-wavelength limit of the superfield actions of some two- and four-dimensional supersymmetric field theories possessing topologically nontrivial soliton solutions. The corresponding topological charges prove to enter the super p-brane actions as the coupling constants. We also give a new general Wess-Zumino-type representation of the d=2 superparticle action via the world-line superfields. It respects invariances both under the target space Poincaré supersymmetry and the gauge group of general reparametrizations of the world-line superspace. In one gauge, it is reduced to the standard PBGS form while in another, it gives rise to a very simple action which displays manifest world-line superconformal symmetry and is directly related to the familiar component action of the superparticle. The fermionic κ-symmetry of the latter can be identified with the odd sector of superconformal symmetry. This identity suggests a simple recipe for building higher-order κ-invariant corrections to the minimal superparticle action.