Human Eye Could Detect Spooky Action At a Distance

KentuckyFC writes "The human eye is a good photon detector--it's sensitive enough to spot photons in handfuls. So what if you swapped a standard photon detector with a human eye in the ongoing experiments to measure spooky-action-at-a-distance? (That's the ability of entangled photons to influence each other, no matter how far apart they might be.) A team of physicists in Switzerland have worked out the details and say that in principle there is no reason why human eyes couldn't do this kind of experiment. That would be cool because it would ensure that the two human observers involved in the test would become entangled, albeit for a short period time. The team, led by Nic Gisin, a world leader on entanglement, says it is actively pursuing this goal (abstract) so we could have the first humans to experience entanglement within months."

Comments

It's better close up

[Chuck Chunder]

FYI.

Re:It's better close up

[mcgrew]

Not in the bars I drink in.

Not quite...

[Timothy Brownawell]

(That's the ability of entangled photons to influence each other, no matter how far apart they might be.)

That's not what entanglement is. It's knowing "this is currently the same as that" or "this is currently the opposite of that" without knowing what "this" or "that" actually is. There is no "connection" or "influence", just a relation that says knowing what "this" is tells you about what "that" is (until it gets changed by interacting with the environment).

Re:Not quite...

[bh_doc]

Emphasis on 'without knowing what "this" or "that" actually is'. Entanglement is "measuring these two things will give related results". Example, you can perform an experiment where you have two photons, which are entangled in their polarisations, and you cannot know beforehand what the results of a measurement of either photon will be. Either photon might turn out to be horizontally polarised (H), or vertically polarised (V), with 50% probability each way. But, the effect of entanglement is that there is a definite relationship between the two, such that if you detect H the other detection will always be V. And vice versa. This is why people often think of it as a "connection" between the two particles, because the result of a measurement of one, which is random, ensures that the measurement of the other is well defined. It's as if the two suddenly know what state each other is in.

Re:Not quite...

[nuclear_zealot]

You're missing the point by describing quantum entanglement as "less mysterious". It was Einstein's (discredited) "hidden variable" theory that used the analogy of two (unknown but predetermined) coins in a pair of envelopes. In that analogy the state of the coins exists but is unknown, and the relationship between the two coins is known. The key feature of entanglement of a pair of photons is that the state of the photons is FUNDAMENTALLY UNKNOWN i.e. "does not exist", but the relationship between the two photons is known.

The only way you can explain that is in the real world is that the instant the state of one photon is measured (remember, quantum theory states that the state does not exist until measured) it them communicates this new information to the other photon (faster than the speed of light).

If we were going to try to stick to the coin analogy, we would be mailing two identical dice in envelopes to two different cities. Who ever opens their letter first roles the dice. Whenever the second person opens their letter and rolls their dice, they get the SAME RESULT as the first person. Both dice are completely random, but they both roll the same result, ***even if they roll their dice at exactly the same instant***.

Now I know you're thinking "the second dice isn't random at all". Well, it doesn't make any sense, but it's exactly as random as the first dice, it's just that the dice are both random in the same way. (btw, this only works for the first dice role. Looking at the die destroys the entanglement)

Einstein said (politely) that "entanglement" was proof that Quantum Theory was a load of fucking bullshit. Problem is: entanglement happens.

On the bright side, you're in exalted company if you think this is a load of bullshit. :)

As for why they are using eyeballs instead of electronic photon detectors... I have no idea. Based on the abstract (not the "fine" article) I'd say they were really working on amplifying entangled photons (which sounds HARD!) and someone said, "hey, if we could cascade >x photons, you could actually see it....". Well, after that, it's just a matter of writing an important-sounding article to justify the expense! :)

And I for one welcome our new entangled overlords.

Re:We can hope

[MoellerPlesset2]

'Quantum consciousness' and all that is complete and utter bunk.

There are no quantum-entanglement phenomena going on in the body.
To put it in simple terms: It's too warm, and too wet.
Or in a bit more advanced terms: The decoherence times are FAR too short to have any chemical effect, much less a biological one. Almost nobody takes Penrose's ideas seriously, but just for the hell of it, the cosmologist Max Tegmark did the math a number of years ago to prove it.
Here's a link to an article about that paper that was in Science.

Many eyes more sensitive than humans.

[w0mprat]

I would have thought they would be experimenting with cats, which Schrodinger demonstrated have strange quantum properties.

Re:Yeouch.

[horati0]

Thanks a lot, Ruiny McRuiner!

Re:We can hope

[Sheafification]

That's not to say that there's no promise in there. I'm not really in favor of the idea of quantum consciousness, but it is interesting to think about.

Not that long ago John H. Conway and Simon Kochen proved a theorem they call the "Strong Free Will Theorem" (which improves on past results; hence the "strong") that shows that if the quantum world satisfies a few axioms then the measured response of a particle is not a function of the past state of the universe. I.e. if we have free will then so do elementary particles, in a certain technical sense.

Of course, with the right axioms you can prove anything. But these particular axioms are testable, and so far the evidence seems to support them; in addition to the fact that they are already commonly believed by quantum physicists.

Here's a link to one exposition.

Re:We can hope

[joeyblades]

>To put it in simple terms: It's too warm, and too wet.

Penrose never claimed that quantum computations were going on in the conscious brain. In fact, he specifically says "non-computational action". What he proposed is that quantum processes in collections of microtubules might manifest macro behaviors at the neuronal level. Tegmark is way off base when he starts ranting about quantum computing and doesn't seem to understand Penrose's theory. As to Tegmark's claims of to rapid decoherence... he doesn't have a clue how hot or how wet or what other factors might be in play at the microtubule level, so really it's just one guy's opinion...

> Almost nobody takes Penrose's ideas seriously...

Well, technically it's Hameroff's theory, but Penrose was a big and influential supporter. However, there are still a few advocates of the idea as evidenced by the large number of books on the subject from Mindell, Walker, Paster, Radin, Rosenblum, Kuttner, Talbot, Stapp, Barrett, Lockwood, Wolberg, Clayton, Stern, Jibu, Yasue, Tuszynski,...(I got tired of typing - I didn't run out of authors)... So "almost nobody" seems a bit of a mischaracterization...

BTW, for the record, I don't personally buy into the Hameroff-Penrose theory of quantum consciousness, but at least I understand it. I wonder if Tegmark ever read "The Emperor's New Mind" or "Shadows Of The Mind"...