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There's an episode of Through the Wormhole called Will Eternity End? which presents many theories about the nature of time.

It is the 9th episode of the 3rd season. I watched it a couple of times, and there's an experiment which is described at the 33m20seg timestamp, reportedly made by Jeff Tollaksen, Yakir Aharonov and others, that appears to defy causality. Here's the transcription of it:

[Tollaksen] But coming from the future, we're saying the present is created out of a combination of the forward evolving and the backward evolving.

[Freeman] As radical as it sounds, Jeff, Yakir, and their colleagues have now tested this idea in the lab.

They give a series of very gentle magnetic nudges to subatomic particles. They measure them at 2:00 and then at 2:30.

They do this over and over again.

Some but not all of the particles are also measured again at 3:00.

And what they found is that taking their measurement at 3:00 seemed to influence the apparently random readings they got at 2:30.

The future seemed to affect the present, even though it hadn't happened yet.

[Tollaksen] If you're trying to understand the present moment, the past is relevant, as we knew before, but the future is just as relevant to the present as the past.

[Freeman] So far, these experiments have only been carried out on the microscopic level, and the effects of the future on the present are very subtle.

Has such experiment actually been carried out?

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  • $\begingroup$ Attempts to build a physics that makes use of both the advanced and retarded waves have a long pedigree that includes some eminent names, but few researchers have stuck with them for very long. The mathematics seems to allow for self-consistent states, but it is unclear how one contains the system. $\endgroup$ – dmckee --- ex-moderator kitten Feb 6 '17 at 18:33
  • $\begingroup$ As explained this violates causality. The long pedigree of retarded and advanced waves to try to derive what you describe in some way, has never had any clarity $\endgroup$ – Bob Bee Feb 7 '17 at 6:44
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I cannot say whether that experiment was truly ever carried out, only that there is a paper (also here) submitted to the American Physical Society by Yakir Aharonov and Jeff Tollaksen which seems to bear resemblance to the experiment you describe.

The quantum mechanics involved seems to make some sense (though not quite enough that I feel confident explaining it without worrying I would mislead).

(There are also related papers here and here with an article on the effect here.)

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  • $\begingroup$ Thanks for finding it. Unfortunately, the answer appears to be "no" to my question though. What a shame. $\endgroup$ – Marc.2377 Jun 10 '17 at 7:31

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