Indeterminacy of wave function

[klw289]

Does the indeterminacy of quantum mechanics arise from the lack of knowledge of the time-evolution of the wave function between measurements or do it have another origin

 

[mfb]

The laws of quantum mechanics are fully deterministic, and we know them very well.
Indeterministic effects arise in some interpretations in measurements, and cannot be avoided. It is not our lack of knowledge of the initial state, its propagation, or lack of precision of the experiments, it is a fundamental property of the universe that you cannot predict the outcome.

 

[jeremyfiennes]

You say "indeterminacy ... is a fundamental property of the universe". Due to the uncertainty inherent in quantum measurements, however, subatomic reality will always appear to us to be indeterminate, even if it isn't really. So there are two possibilities, both neither provable nor refutable, and hence equally valid. Namely that reality is a) indeterminate; b) determinate. Why is the second never considered?

 

[Nugatory]

So there are two possibilities, both neither provable nor refutable, and hence equally valid. Namely that reality is a) indeterminate; b) determinate. Why is the second never considered?

It is considered, in some interpretations. The entire question doesn't get much air time (and there are people who will say that what little it does get is still too much) for exactly the reason that you have pointed out: It's neither provable nor refutable.

 

[jeremyfiennes]

But the "inherently indeterminate" hypothesis is likewise neither provable nor refutable. That is my point. One hypothesis is declared to be the case, without proof. And the other is ignored. What did it do wrong?

 

[mfb]

But the "inherently indeterminate" hypothesis is likewise neither provable nor refutable.

It is, see the Bell inequality.
There is a lot of freedom where you place the description of "indeterminate", but it has to be somewhere.