Paradox 9.3 | Bell’s theorem, 4.2

The meaning of the phrase “counterfactual definiteness” in quantum mechanics or Bell’s theorem is not the same as that in the superdeterminism theory. They are two different concepts.

In the superdeterminism theory, no non-local wave function collapse effect is needed, as all are pre-programmed, including the experimenters’ choices of measurement axes. Superdeterminism assumes that the world is classical and classically deterministic.

In such a situation, it is counterfactual definite in a sense that there is no quantum superposition. A system has a definite classical state even before any measurements.

However, it is not counterfactual definite in sense that there are no alternatives. It is not meaningful to ask, “What if the experimenter had chosen another measurement axis?”

Bell’s theorem assumes that the types of measurements performed at each detector can be chosen independently of each other and of the hidden variable being measured. In order for the argument for Bell’s inequality to follow, it is necessary to be able to speak meaningfully of what the result of the experiment would have been, had different choices been made. This assumption is called counterfactual definiteness.

But in a deterministic theory, the measurements the experimenters choose at each detector are predetermined by the laws of physics. It can therefore be argued that it is erroneous to speak of what would have happened had different measurements been chosen; no other measurement choices were physically possible.

— Wikipedia on Superdeterminism

 
Superdeterminism is cheating.

— Me@2012-11-24 11:21:01 AM

2012.11.27 Tuesday (c) All rights reserved by ACHK