At some stage, this complex quantum linear superposition … [evolving by Schrodinger's equation for procedure U] … squared according to the procedure R. Only one … the one observed [in the cloud chamber] by the experimenter. According … the gravitational fields of the various alternatives reaches … always appears as a single whole [i.e., as a quantum particle] and not as some fraction of a whole, it must … [If a detector is placed at one of the slits, then the interference pattern disappears]
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