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arXiv 1611.03444quant-phphysics.hist-ph
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我们从贝尔实验的计算机模拟中学到了什么?

What do we learn from computer simulations of Bell experiments?

Marian Kupczynski

摘要:

与反事实的确定性相反,量子理论告诉我们,测量仪器并不是被动地读取物理可观察量的预定值。反事实确定性允许证明贝尔不等式。如果正确地考虑了量子测量的上下文特征,这些不等式的证明就可能不被完成。在最近的计算机模拟的理想化贝尔实验预定连续的测量结果,为每个设置和预定的时间延迟,他们的注册计算。时间窗口和时间延迟用于选择各种样本。使用这些选定的样本估计的相关性与量子理论的预测一致,并且时间窗口依赖性与在一些真实实验中观察到的依赖性相似。这是一个重要的例子,说明如何在不引起量子非定域性的情况下解释相关性。然而,通过使用适当的后选择,可以证明任何事情。由于在后选择之前生成的样本可能不会像使用量子预测生成的有限样本那样显著地违反贝尔不等式,因此人们可能不会得出反事实确定性不能区分经典物理和量子物理的结论。此外,我们表明,对于每个选择的时间窗口存在一个上下文的隐变量概率模型与作者使用的后选择程序相一致,这解释了为什么他们能够重现量子预测。

英文摘要:

Contrary to counterfactual definiteness quantum theory teaches us that measuring instruments are not passively reading predetermined values of physical observables. Counterfactual definiteness allows proving Bell inequalities. If the contextual character of quantum measurements is correctly taken into account the proofs of these inequalities may not be done. In recent computer simulations of idealized Bell experiment predetermined successive outcomes of measurements for each setting and predetermined time delays of their registrations are calculated. Time windows and time delays are used to select various samples. Correlations, estimated using these selected samples are consistent with the predictions of quantum theory and the time window dependence is similar to the dependence observed in some real experiments. It is an important example how correlations can be explained without evoking quantum non-locality. However by using a suitable post-selection one may prove anything. Since before the post-selection generated samples may not violate Bell inequalities as significantly as finite samples generated using quantum predictions thus one may not conclude that counterfactual definiteness is not able to distinguish classical from quantum physics. Moreover we show that for each choice of a time window there exists a contextual hidden variable probabilistic model consistent with the post-selection procedure used by the authors what explains why they are able to reproduce quantum predictions.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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