On the Effects of a Bulk Perturbation on the Ground State of 3D Ising   Spin Glasses
  We compute and analyze couples of ground states of 3D spin glasses before and after applying a volume perturbation which adds to the Hamiltonian a repulsion from the true ground state. The physical picture based on Replica Symmetry Breaking is in excellent agreement with the observed behavior. 
Enzo Marinari and Giorgio Parisi