In the system of a pair of quantum-entangled neutral kaons from meson decays, when one kaon collapses into the KS state, the other will collapse instantaneously into the KL state, due to entanglement and nonlocality. However, if the alternative hypothesis is correct and there is a time window during which one kaon is unaware that the other has decayed, some quantum mechanically prohibited KSKS decays may occur. We calculate the branching ratios of KSKS in vector meson decays under locality hypothesis and compare them with experimental results. We show that the branching ratio of J/ψ → KSKS under locality assumption is already excluded by the BESIII experimental upper limit. Additional experimental results are proposed to perform this test in the future.

中文翻译：

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通过向量介子衰减到 KSKS 的量子非定域性测试

在来自介子衰变的一对量子纠缠的中性介子系统中，当一个介子坍缩成ķ小号状态，另一个会瞬间崩溃到ķ大号状态，由于纠缠和非定域性。然而，如果替代假设是正确的，并且存在一个时间窗口，在此时间窗口中一个 kaon 不知道另一个 kaon 已经衰变，那么一些量子力学禁止ķ小号ķ小号可能会发生衰变。我们计算支化率ķ小号ķ小号向量介子在局部性假设下衰减，并将它们与实验结果进行比较。我们证明了支化率Ĵ/ψ → ķ小号ķ小号在局部性假设下已经被 BESIII 实验上限排除。提出了额外的实验结果以在未来执行该测试。