When discussing EPR experiments on this forum I made the claim that Bell's theorem does not prove classical determinism false because there is always the possibility that the correlations between distant measurements can be a result of the common past shared by particle source and the two detectors. A counterargument to this "loophole" is that one can use microwave photons from a period close to big-bang, to chose the detector orientation, and those particles do not necessary have a common past. Now, my question is as follows: If two particles are created at the big-bang in such a way that no light signal could travel between them, does QM, as we know it, still apply? For example, I would expect that two charged particles in that situation would not experience Coulombian force, therefore the potential used to calculate the Hamiltonian necessary for the derivation of Schrodinger's equation would be different than for a "normal" pair of particles. Thanks.