I guess I just view the wavefunction as an inherently multiparticle function on a configuration space. The concept of approximating single-particle states seem

I guess I just view the wavefunction as an inherently multiparticle function on a configuration space. The concept of approximating single-particle states seems peculiar to me; it seems simpler just to have one state for an entire system (and the corresponding probabilities of what measurements you'll get on that system, regardless of how the system is distributing spatially). Then again, we're coming from different research backgrounds so we probably have a different way of looking at it ;) Quantum entanglement doesn't seem to be particularly unusual any more so than the fact that electron-electron correlation must be taken into effect when computing energy levels with some kind of QMC. All particles within a quantum system are correlated, so entanglement just kind of falls naturally out of that; I'm not assuming any kind of locality. I suppose what you're saying is that collapse is defined as the process of "fixing" these correlations?