I don't quite understand why super symmetry is spontaneously broken if the vacuum state has non-zero energy. If the vacuum state has non zero energy, this means the the SUSY generators have no common eigen-state with zero eigenvalue. I think in this case, SUSY will turn a one-particle state into a state which is a linear combination of the vacuum and many particle states. Is this the reason we say that SUSY is broken if the vacuum state has non-zero energy ?