We now get to where QM takes over: How is this all possible? We do not understand the nature of quanta. They cannot be thought of as BBs and we can apply our understanding of the macro universe (Things roughly larger than an atom) to the behavior of a quantum. What happens when we create entangled particles? We get what appears to be 2 quanta, but if you take a quantum apart you get quarks and that is not what we have. OPINION: We get a single quantum that appears in 2 places at once.
Old Pilot’s Entangled Cat (With apologies to Erwin Schrodinger)
Consider this variation on Schrodinger's Cat: The box is rigged with partitions that allow the box to be separated into 2 boxes without observing the contents. At the end of the hour when the box, by Copenhagen, contains a cat that is both alive and dead, we split the box into 2 boxes. We can now separate both boxes that still contain the Cat Fog as far apart as we wish and look in either box. If we find a dead (or alive) cat then there must also be a alive (or dead) cat in the other box because it is the same cat. Note, if one box has a live cat, then the other box must have a dead cat because the Conservation Laws require that the Mirror Indeterminacy be preserved. To be consistent and QM is ALWAYS consistent, when we separated the boxes the PSI Function of the cat (or the now entangled radioactive atom) had the value Alive and Dead (Un-decayed and Decayed) all we did was separate the cat and atom, the PSI function must still maintain both values. Since the cat and atom are now in 2 locations, the PSI Function will collapse to both solutions.
We cannot "prove" quanta exist in 2 locations at one time, since when observed they exist in only 1 location. But, to explain quantum behavior, that is about the only choice.