Superdeterminism: Difference between revisions

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In [[quantum mechanics]], '''superdeterminism''' is a hypothetical class of theories that evade [[Bell's theorem]] by virtue of being [[hard determinism|completely deterministic]]<ref>{{cite arXiv |title=Rethinking determinism |eprint=arXiv:1912.06462|last1=Hossenfelder|first1=S.|last2=Palmer|first2=T. N.|class=quant-ph|year=2019}}</ref>. It is conceivable that someone could exploit this loophole to construct a [[local hidden variable theory]] that reproduces the predictions of quantum mechanics. Superdeterminists do not recognize the existence of genuine chances or possibilities anywhere in the cosmos.
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 fully 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. Since the chosen measurements can be determined in advance, the results at one detector can be affected by the type of measurement done at the other without any need for information to travel faster than the speed of light.