The BIG Bell Test—Global physics experiment challenges Einstein with the help of 100,000 volunteers

May 9, 2018, ICFO
The BIG Bell Test Initiative, November 30th, 2016. Credit: ICFO

On November 30th, 2016, more than 100,000 people around the world contributed to a suite of first-of-a-kind quantum physics experiments known as The BIG Bell Test. Using smartphones and other internet-connected devices, participants contributed unpredictable bits, which determined how entangled atoms, photons, and superconducting devices were measured in 12 laboratories around the world. Scientists used the human input to close a stubborn loophole in tests of Einstein's principle of local realism. The results have now been analysed, and are reported in this week's Nature.

In a Bell test (named for the physicist John Stewart Bell), pairs of such as photons are generated and sent to different locations, where particle properties such as the photons' colours or time of arrival are measured. If the measurement results tend to agree, regardless of which properties we choose to measure, it implies something very surprising: either the measurement of one particle instantly affects the other particle (despite being far away), or even stranger, the properties never really existed, but rather were created by the measurement itself. Either possibility contradicts , Einstein's worldview of a universe independent of our observations, in which no influence can travel faster than light.

The BIG Bell Test asked human volunteers, known as Bellsters, to choose the measurements, in order to close the so-called "freedom-of-choice loophole"—the possibility that the particles themselves influence the choice of measurement. Such influence, if it existed, would invalidate the test; it would be like allowing students to write their own exam questions. This loophole cannot be closed by choosing with dice or random number generators, because there is always the possibility that these physical systems are coordinated with the entangled particles. Human choices introduce the element of free will, by which people can choose independently of whatever the particles might be doing.

Led by ICFO-The Institute of Photonic Sciences, in Barcelona, the BIG Bell Test recruited participants worldwide to contribute unpredictable sequences of zeros and ones (bits) through an online video game. The bits were routed to state-of-the-art experiments in Brisbane, Shanghai, Vienna, Rome, Munich, Zurich, Nice, Barcelona, Buenos Aires, Concepción Chile and Boulder Colorado, where they were used to set the angles of polarizers and other laboratory elements to determine how entangled particles were measured.

Participants contributed with more than 90 million bits, making possible a strong test of local realism, as well as other experiments on realism in quantum mechanics. The obtained results strongly disagree Einstein's worldview, close the freedom-of-choice loophole for the first time, and demonstrate several new methods in the study of entanglement and local realism.

The BIG Bell Test Initiative, November 30th 2016. Credit: ICFO
THE ICFO Quantum Memory EXPERIMENT

Each of the 12 labs around the world carried out a different experiment, to test local realism in different physical systems and to test other concepts related to realism. ICFO contributed with two experiments. The ICFO 1 team, composed of Pau Farrera and Dr. Georg Heinze, led by ICREA Prof. at ICFO Hugues de Riedmatten, performed a Bell test using entanglement between two very different objects: a single photon and a trapped cloud with millions of atoms. This cloud acted as a "quantum memory" storing for some time the matter part of the entangled state, and transferring it later into another single photon. The entanglement was analysed using optical interferometers and single photon detectors. The measurement settings of these interferometers were chosen by the provided by the Bellsters. Specifically, the random numbers were deciding the voltages that were applied to a piezoelectric device attached to the interferometers. The results obtained clearly contradict the concept of local realism.

The setup of the experiment. Credit: Jian-Wei Pan's Gruop

The ICFO 2 team performed a Bell test using entanglement between two single photons of different color generated with a solid-state photon pair source. The researchers, Dr. Andreas Lenhard, Alessandro Seri, Dr. Daniel Rieländer, and Dr. Margherita Mazzera, led by ICREA Prof. Hugues de Riedmatten, could generate narrow-band photon pairs in several discrete frequency modes. After separating the photons of the pair, their entanglement was analysed using, in each of the two arms, an electro-optic modulator to overlap the different frequency modes and an optical cavity as spectral filter. The random numbers provided by the Bellsters were exploited to choose the voltages driving both the modulation amplitude and phase of the electro-optics modulators. The experiment was done in collaboration with the ICFO researchers Dr. Osvaldo Jimenez, Dr. Alejandro Mattár and Dr. Daniel Cavalcanti, led by ICREA Prof. at ICFO Antonio Acín. They developed a model to describe the generated and find the optimal measurements to contradict local realism. From the experiment performed on November 30th, 2016, local realism theories can be ruled out with a significance level of 3 standard deviations, while a stronger violation, of more than 8 standard deviations, was achieved in the weeks following the Big Bell Test day by performing longer measurements with stored human random numbers.

Hugues de Riedmatten, ICREA Professor at ICFO: "The BBT was a great experience. It was amazing to see random numbers created by Bellsters all around the world take control of our experiments in real time, and to see so many people participating in a quantum physics experiment."

Carlos Abellan, researcher at ICFO and instigator of the project: "The BIG Bell Test was an incredibly challenging and ambitious project. It sounded impossibly difficult on day zero, but became a reality through the efforts of dozens of passionate scientists, science communicators, journalists and media, and especially the tens of thousands of people that contributed to the experiment during November 30th, 2016."

Morgan Mitchell, leader of the BBT project and ICREA Professor at ICFO: "What is most amazing for me is that the argument between Einstein and Niels Bohr, after more than 90 years of effort to make it rigorous and experimentally testable, still retains a human and philosophical element. We know that the Higgs boson and gravitational waves exist thanks to amazing machines, physical systems built to the laws of physics. But local realism is a question we can't fully answer with a machine. It seems we ourselves must be part of the experiment, to keep the Universe honest."

The BIG Bell Test team once again would like to thank the thousands of participants who so generously and enthusiastically contributed to this initiative. Without this essential contribution, the experiment would have never been possible.

Explore further: Quantum physics entangled with human randomness

More information: Challenging local realism with human choices, Nature (2018). nature.com/articles/doi:10.1038/s41586-018-0085-3

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27 comments

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dnatwork
5 / 5 (1) May 09, 2018
I thought humans and video games were inherently non-random.
Bugsbunny67
5 / 5 (1) May 09, 2018
Where you see randomness I see structure.
Hyperfuzzy
1 / 5 (2) May 09, 2018
So. instead of logic; we'll try using possibility theorem-non-formal-theory that allows the existence of the non-existent, ....

Huh? Nonsense, speed of light is relative speed of wavelet, i.e. original wavelet, how fast did it go by? I think it was the measured Period!
NoStrings
5 / 5 (1) May 09, 2018
To paraphrase, the question is: are 100,000 fools smarter than Einstein? Because what they are doing, makes little sense other than that.

Why not go a normal path, and let them vote on that? You know the answer: Trump.
KBK
1 / 5 (1) May 09, 2018
Look up the book, 'the field' by Lynn mctaggart. It deals principally with this issue. (PDF)

about a quarter (seemingly) of the book is the bibliography and index, for those who like to properly suss out where the data originates from.

It's all about science, and the properties of correct regimen in the testing, as it gets into some very messy waters.

the conclusion is that the universe is an information field (also: Max Planck's conclusion) and collected bits of consciousness, ie, collected information, can be directed and does indeed control and direct outcome. through time. Ie, temporally invariant. Ie, time is an illusion: Fully proven.
KBK
1 / 5 (1) May 09, 2018
A fundamental point proven by the veritable multitude of excellent experiments on record (in the book), Done by distinguished and accredited scientists... and vetted as correctly done and verified as good science by the Federal government's "us academy of sciences' (in a many year long fine toothed comb effort), is that local reality is an act of consciousness creation,and you can chose to believe and project that none of that psychic crap is true and this will work for you.

That objectivity is a joke and subjective reality is all there is. Which science tells you all the time. Objectivity is a mental push and desire by a subset of linear minded science (human desires) and the information field allows for that. Whoops!!

That the quantum information field truly does underwrite all of Newtonian reality.
Da Schneib
5 / 5 (3) May 09, 2018
Injecting randomness by the actions of thousands of independent volunteer researchers is an ingenious way of testing the randomness loophole in Bell tests. Since they cannot have interacted, the randomness is guaranteed unless we question human freedom of choice. To further isolate the choices from the results, the choices were randomly chosen from the collection generated by the volunteers. This is how the universe works. It's either non-local or non-realistic, no matter how you cut it.
tttito
not rated yet May 10, 2018
The point is that information exchange between observe is local: "... both A and B subsist as superpositions of observers that saw heads or tails. It is only when they exchange information that they agree, i.e that the states of observer A and B collapse respectively with respect to observer B and observer A into states where the coin measurement has yielded the same outcome."
https://arxiv.org...206147v1 (page 4)
Tyrant
5 / 5 (1) May 10, 2018
Well Da Schneib, human freedom of choice is merely an illusion in a deterministic universe.
KBK
1 / 5 (1) May 10, 2018
Injecting randomness by the actions of thousands of independent volunteer researchers is an ingenious way of testing the randomness loophole in Bell tests. Since they cannot have interacted, the randomness is guaranteed unless we question human freedom of choice. To further isolate the choices from the results, the choices were randomly chosen from the collection generated by the volunteers. This is how the universe works. It's either non-local or non-realistic, no matter how you cut it.


If you look at what I posted, and follow it's logic, it turns your projections - into gobbledygook.

But, the information field and it's behaviour, allows for that. So you can get to what your project, depending on your level of interaction with other 'directed forces' within the frameworks of the 'information field'.

Esoteric sciences have been telling you this for thousands of years. Modern science does as well.

Where ignorance is possible, and can shape reality effectively.
Hyperfuzzy
1 / 5 (1) May 10, 2018
or just use logic, this is nonsense
rrwillsj
5 / 5 (1) May 10, 2018
Now I'm going to stay over here. Lounging in the shade with a beer in my hand.

While you go over there. Yep, right next to that active volcano. And you use your vast mental powers to ",,,shape reality effectively...."

Woe! That's some hotfoot you got going, fella! Oh, he's already run off to the shore to sooth his melting toes.

Bummer...

It's always a good laugh when the loons sprout that gibberish "mind over matter". Cause Reality don't mind and you simpleton monkeys don't matter.
Hyperfuzzy
not rated yet May 10, 2018
Now I'm going to stay over here. Lounging in the shade with a beer in my hand.

While you go over there. Yep, right next to that active volcano. And you use your vast mental powers to ",,,shape reality effectively...."

Woe! That's some hotfoot you got going, fella! Oh, he's already run off to the shore to sooth his melting toes.

Bummer...

It's always a good laugh when the loons sprout that gibberish "mind over matter". Cause Reality don't mind and you simpleton monkeys don't matter.

your challenge is like the challenged
Bugsbunny67
3 / 5 (2) May 10, 2018
Those who say that the reality is not real must be the same as those who abuse of others upon their own fantasies in which the abused are not real but only ethereal of some sort...

Of course the world is real, and it is probable to a very high degree that it is not entirely local. If there is something I know for sure is that the world is real...
Da Schneib
5 / 5 (2) May 10, 2018
Be careful, @Bugs, not to confuse philosophical reality with physics reality. By "reality" in physics physicists mean that every parameter of a particle has a theoretically measurable value at all times. There are two possible explanations of the outcome of Bell tests: non-reality, that is, not all parameters have even theoretically measurable values at all times, and non-locality, that is, local causes do not always have local effects and vice-versa. We're still working out if that's actually two different things or not.
Bugsbunny67
3 / 5 (2) May 10, 2018
I know that but history and sciences, especially applied sciences, are a proof of the Reality. All sciences are based on an absolute reality, it is all there is. Nothing outside reality (or nature) is needed... How about Napoleon? Was he real? Of course... I am speaking of physics not philosophy. Unreality is only philosophical, certainly unphysical...
Da Schneib
not rated yet May 10, 2018
From a philosophical point of view one can argue that there is no other person but oneself. This of course obviates any possibility of comparing observations with anyone else, and negates science. Unfortunately for this point of view science is enormously (and unreasonably) successful. Computers, Moon landings, refrigerators, jet aircraft, and microwave telecommunications spring immediately to mind.
Bugsbunny67
5 / 5 (1) May 10, 2018
Yep!
Whydening Gyre
not rated yet May 10, 2018
Injecting randomness by the actions of thousands of independent volunteer researchers is an ingenious way of testing the randomness loophole in Bell tests. Since they cannot have interacted, the randomness is guaranteed unless we question human freedom of choice. To further isolate the choices from the results, the choices were randomly chosen from the collection generated by the volunteers. This is how the universe works. It's either non-local or non-realistic, no matter how you cut it.

I prefer real with a smattering of non-locality sprinklled on top....
Hyperfuzzy
1 / 5 (1) May 10, 2018
anyway; back in reality world, i see only charge that exist, inside and outside the theory; even give rise to the thought
drrobodog
not rated yet May 11, 2018
the randomness is guaranteed unless we question human freedom of choice.

I'm confused, how can human choice be random? What is the cause of the randomness, and if it exist why not utilize the source to generate random numbers?
Kron
1 / 5 (1) May 12, 2018
I've always been a proponent of classical physics and have tried to reconcile events which seem to conflict with classical phenomena. The older I grow, the more weird the concept of time and space seem to get.

I've been experiencing precognitive dreams since a very young age and have always rationalized them as being chance occurences that evolve from data available to me before I dream. A low percentage of my dreams occur in the future, so I've always just said to myself that it isn't precognition or seeing the future, but rather that what I've experienced is either coincidental/or that my brain has taken past events and calculated out a future scenario.

Lately I've been experiencing an increase of these types of dreams (which to me negates pure chance), so I'm left with these dreams either being calculated scenarios or prescience. The nature of them has got me leaning toward prescience as some events just seem too random, and no connection to their cause apparent.
Hyperfuzzy
not rated yet May 12, 2018
.. seem too random, and no connection to their cause apparent.

Try using logic
Hyperfuzzy
not rated yet May 12, 2018
the randomness is guaranteed unless we question human freedom of choice.

I'm confused, how can human choice be random? What is the cause of the randomness, and if it exist why not utilize the source to generate random numbers?

nothing is random. it only means you can't guess the sequence, or since we don't respect causality, we say it is non-causal
Hyperfuzzy
not rated yet May 12, 2018
every set of activity is causal; maybe not what you were expecting; it's only the interactions of an infinite set of charges; since this is mostly a summation, you can't choose what to leave out

you seem to be missing logic
Hyperfuzzy
not rated yet May 12, 2018
by the way Higgs and Einstein have no valid premise; if you accept the later then excuse me; i speak a different language, only began with truth. only need one
Hyperfuzzy
not rated yet May 12, 2018
a measurement defined by the communication media [ Calibration? ; Physics?; confusing (alive Xor dead) vs (alive and dead?] vs logic; premise? [no such thing as a photon] each field has a unique center! what are you talking about?

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