But the wave function ψ is not a physical object like, for example, an atom, which has an observable mass, charge and spin, as well as internal degrees of freedom.
In this case, there is no real mystery in that this mathematical form of the wave function ψ must change abruptly after a measurement has been performed.
[11]Niels Bohr, also a founder of the Copenhagen interpretation, wrote: all unambiguous information concerning atomic objects is derived from the permanent marks such as a spot on a photographic plate, caused by the impact of an electron left on the bodies which define the experimental conditions.
The description of atomic phenomena has in these respects a perfectly objective character, in the sense that no explicit reference is made to any individual observer and that therefore, with proper regard to relativistic exigencies, no ambiguity is involved in the communication of information.
As John Bell inquired, "Was the wave function waiting to jump for thousands of millions of years until a single-celled living creature appeared?
"[14] The prominence of seemingly subjective or anthropocentric ideas like "observer" in the early development of the theory has been a continuing source of disquiet and philosophical dispute.
[17] The uncertainty principle in its standard form describes how precisely it is possible to measure the position and momentum of a particle at the same time.