Originally posted by Palynka
I don't believe you. 😛 I'm sure you could if you cared to bother. If you can't be arsed, just say so (believe me, I understand). If you can but you really don't think you can explain it accurately, at least tell me which book/article/paper...

Perhaps you can look at it from the perspective of the Schrödinger equation. The Hamiltonian contains two terms: a kinetic term (with the Laplacian) and a potential term. The kinetic term implies an energy "penalty" for having large variations in the wavefunction (i.e. small wavelength = high energy). The potential term implies a penalty for having particles at positions with a large positive interaction (repulsive interactions) with other particles. So the ground state of a particle, the "default" state if you wish, will try to obtain a smooth wavefunction, avoiding places with high interaction energy (or equivalently seeking places with high negative interaction - attractive interactions), subject to the constraint that the wavefunction must be normalized. Thus the potential term is what causes "forces" that manifest itself in the classical world (in addition to the symmetrization requirement).