An Exceptionally Simple Argument Against the Many-worlds Interpretation: Further

It is argued that the components of the superposed wave function of a measuring device, each of which represents a definite measurement result, do not correspond to many worlds, one of which is our world, because all components of the wave function can be measured in our world by a serious of protective measurements, and they all exist in this world. In standard quantum mechanics, it is postulated that when the wave func-tion of a quantum system is measured by a macroscopic device, it no longer follows the linear Schrödinger equation, but instantaneously collapses to one of the wave functions that correspond to definite measurement results. However, this collapse postulate is ad hoc, and the theory does not tell us why and how a definite measurement result appears. There are in general two ways to solve the measurement problem. The first way is to integrate the collapse evolution with the normal Schrödinger evolution into a unified dynamics, e.g. in the dynami-cal collapse theories (Ghirardi 2008). The second way is to reject the collaps