Experiment with gamers, random numbers and entanglement

[Spathi]

https://www.wired.com/story/this-random-video-game-powers-quantum-entanglement-experiments/

In the next month—mostly on November 30—about 100,000 people around the world would play the simplistic keyboard-mashing game in response to a publicity campaign run by physicists. It turns out, the random bits they generated would be used in an ambitious new experiment to test the weirdest predictions of quantum mechanics.

So they designed a videogame with six levels. In the first level, you press 1’s and 0’s to navigate through a city. The computer calculates a score for how unpredictable your typing is, and you have to achieve a certain amount of randomness to pass the level. Behind the scenes, your input is also teaching a machine-learning algorithm your typing habits. In the second level, the computer tries to guess what you will type while you try to fool it. The levels alternate between frenzied key mashing and cool, calculated pecks.

Ultimately, every single experiment indicated that yes, entanglement exists. Which has implications beyond fundamental science, says physicist David Kaiser of the Massachusetts Institute of Technology.

I don't understand the principle of this experiment. The gamers produced random numbers, and what was done with these numbers then? Was the value like <S> in CHSH inequalities computed, and was it smaller than 2?
In ther words: the correlations for the random numbers generated by gamers violated the Bell inequelities, or not? Or maybe these numbers were simply used for choosing the polarizers orientations, instead of usual radiactive decay randomizers?

 

[DrChinese]

https://www.wired.com/story/this-random-video-game-powers-quantum-entanglement-experiments/

I don't understand the principle of this experiment. The gamers produced random numbers, and what was done with these numbers then? Was the value like <S> in CHSH inequalities computed, and was it smaller than 2?
In ther words: the correlations for the random numbers generated by gamers violated the Bell inequelities, or not? Or maybe these numbers were simply used for choosing the polarizers orientations, instead of usual radiactive decay randomizers?

The Big Bell Test used the inputs of many independent minds (about 100,000) to create 97,347,490 "random" values (bits) for use in a series of coordinated Bell tests.

13 separate Bell Tests were run in labs around the globe on 30 November 2016. They would otherwise be considered traditional, mostly with a Bell Inequality of S<=2 (as you mention). In all cases the inequality was violated, which was a surprise to (probably) no one.

https://arxiv.org/abs/1805.04431

The overall purpose was to demonstrate - if such a demonstration was needed - that the free will of persons could be harnessed and used for selection of measurement choices in experiments. This provides strong evidence that the so-called "freedom of choice" loophole* could be considered closed. That loophole relates to the hypothetical existence of "superdeterministic" forces that control selection of measurement choices in Bell tests without the knowledge of the person (or computer) making those choices. This experiment shows that if superdeterministic forces exist, that 100,000 people are simultaneously controlled by them.

In the spirit of trying to cover all the bases, this is a cool experiments with contributions by physicists in a global cooperative. Many top entanglement teams were involved.

The article you linked to gives a somewhat misleading picture of the experiment. First, this experiment was not a "proof" of the existence of entanglement. That was done back in the 1970s and 1980s. The gamers themselves ("Bellsters") merely provided data bits to be used, rather than using the random number generator on a computer*.*Not everyone believes there is a freedom of choice loophole (I don't for example) that needs to be closed.

**Random numbers are not required for a successful Bell test, but a lot of experiments use them to demonstrate that there are no behind-the-scenes forces at work which might otherwise explain entanglement in a local realistic manner. It is not strictly necessary to vary measurement settings in every Bell test, once this particular loophole was closed.

 

[Spathi]

13 separate Bell Tests were run in labs around the globe on 30 November 2016.

Sorry, I still need to clarify: these were the standard physical experiments with photons and polarizers, or electrons and Stern–Gerlach apparatus?
CHSH experiment, as far as I understand, is the analogue of the Bell test. For me it is maybe easier to understand the CHSH variant:

https://en.wikipedia.org/wiki/CHSH_inequality

Four separate subexperiments are conducted, corresponding to the four terms {\displaystyle E(a,b)}

in the test statistic S (2, above). The settings a = 0°, a′ = 45°, b = 22.5°, and b′ = 67.5° are generally in practice chosen — the "Bell test angles" — these being the ones for which the quantum mechanical formula gives the greatest violation of the inequality.

So the random numbers produced by the gamers deterimened the choice of these angles (0, 45, 22.5, 67.5)?

 

[DrChinese]

1. Sorry, I still need to clarify: these were the standard physical experiments with photons and polarizers, or electrons and Stern–Gerlach apparatus?

2. So the random numbers produced by the gamers deterimened the choice of these angles (0, 45, 22.5, 67.5)?

1. If you look at the reference I provided for the Big Bell test in post #2: Table 1 shows the 13 different experiments performed. Most were photon polarization. (I don't see any with electrons.)

2. The answer is yes (at least for those experiments with photon polarization).

 

[Spathi]

*Not everyone believes there is a freedom of choice loophole (I don't for example) that needs to be closed.

I have my own understanding of this: the authors of these experiments (with gamers and with quasars) didn't really want to "close one more loophole" in the BT, but they wanted to show, that they don't find insane the idea that everything correlates with everything, and these correlations affect our free will (superdeterminism). Do you agree with my interpretation?

 

[Nugatory]

Do you agree with my interpretation?

No, you have it pretty much backwards.
These experiments are showing how implausible the superdeterministic explanation is.