Connected sets of solutions of symmetric elliptic systems

The purpose of this paper is twofold. First we study bifurcations of connected sets of critical orbits of some invariant functional from a given family of critical orbits. We use techniques of equivariant bifurcation theory to obtain a Rabinowitz type alternative for symmetric gradient operators. The second aim is to apply the abstract results to study orbits of nonconstant solutions of a nonlinear Neumann problem.