The results were 18 standard deviations away from what you’d expect based on Bell’s theorem, which is a strong indication that superposition of temporal order is a fundamental feature of quantum mechanics.
But the experiment remains where entanglement was a few decades ago: There are plenty of loopholes. For example, many photons are lost during the experiment (about 1 percent of those sent into it come out the other side to be measured). It remains technically possible that the losses were preferentially occurring among a subset of photons that would otherwise restore correlations that are compatible with hidden variables.
The team also hasn’t separated the hardware by far enough
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