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Esalen Seminar on the Nature of Reality Poster
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THE REALITY PRIZE
In the late 1970s, Esalen Institute co-founder Michael Murphy decided to invite physicists down to Big Sur to see what might happen. One of Mike's speculations was that “Perhaps a new kind of inspired physicist, experienced in the yogic modes of perception, might emerge to comprehend the further reaches of matter, space and time.” So it happened that physicist Saul-Paul Sirag and myself found ourselves leading workshops on quantum mechanics for Esalen guests and holding yearly invitational conferences for selected scientists focused mainly on the theme of Irish physicist John Stewart Bell's non-locality theorem for quantum-entangled systems.
Quantum theory is one of our most successful mathematical tools for understanding the behavior of Nature at her most basic level. This theory has never made a wrong prediction and some of its results agree with experiment up to 13 decimal places. However its success is marred by what one might call The Reality Crisis. Though I have struggled with this theory for more than fifty years, I cannot tell my son Khola a simple story about how the world works on the quantum level. And neither can anyone else.
Quantum physicists represent the world in two ways depending on whether the world's being looked at or not. Waves of possibility when not looked at; And an actual particle when we look. Plus physicists don't really know what “looking” means — an embarrassing situation called “the measurement problem”. Wanna stump a physicist? Ask him (or her) what they think it takes to turn many shimmering quantum possibilities into one hard quantum fact.
Oddly enough, The Reality Crisis (physicist's inability to tell a good quantum story) does not hamper at all our ability to use this wonderful tool to make successful predictions. So, for the most part, practical physicists have consigned “thinking about reality” to the philosophers, to physicists who have already made their mark in the world and to amateurs (from the French word “to love”) who have no reputation to lose. “Do not keep saying to yourself if you can possibly avoid it,” warned physicist Richard Feynman, 'But how can it be like that?' because you will go 'down the drain' into a blind alley from which nobody has yet escaped. Nobody knows how it can be like that.”
To explain how one particle becomes actual is puzzling enough, but the stakes are raised once two particles are involved, especially if they happen to be created in a state of “quantum entanglement”. Then, when unlooked at at least, the two entities do not possess their own attributes. Only the union of the two is in a definite state of being, until a measurement is made. Erwin Schrōdinger was the first to point out the peculiar nature of entangled quantum systems and to comment that this strange mode of being was what most distinguished the quantum world from everyday stuff..
But in Schrōdinger's day, entangled quantum systems were hard to come by. So quantum entanglement, for the most part, remained a theoretical curiosity, if it was even mentioned at all.
That all changed in 1964, when a physicist named John Stewart Bell, whose hobby happened to be quantum reality, discovered, during a sabbatical leave from his day job at CERN accelerator, what is now know as “Bell's Theorem.”
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The Bell Experiment
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Imagine a source S of polarization-entangled photon pairs A and B. Photon A is sent to Alice and photon B to Bob who each have a device that measures photon polarization. One of the important features of a quantum measurement is that Alice cannot just ask “what properties does her A photon actually possess?” but must make a choice of what attribute to ask about and which attributes to leave unknown.
Quantum attributes come in complementary pairs (and often triplets). If you ask about position, you forego finding out about momentum, a discovery attributed to Heisenberg, known as “the uncertainty principle”. Photon polarization happens to be one of those quantum attributes that is triplely uncertain, so when Alice chooses to measure one photon polarization plane, she necessarily forfeits all knowledge of the other two polarization planes.
At both Alice and Bob's stations, imagine a clock face that represents the direction that the two experimenters choose to interrogate their photon's unknown polarization. If Alice chooses to ask at 12 o'clock, a PLUS in her detector means that her A photon polarization is Vertical (V); a MINUS means that its polarization is Horizontal (H).
Two features of this system are typical of an entangled state:. 1. No matter what their clock settings, each observer always gets a random sequence of PLUSs and MINUSs; 2. Whenever Alice's setting is the same as Bob's, if Alice gets a PLUS, Bob will always get a MINUS and vice versa. Their results are said to be 1. Perfectly random and 2. Perfectly anti-correlated.
Since polarization-entangled states were almost non-existent in 1964, nobody really knew if this would actually happen to Alice and Bob, but a simple quantum calculation gives the result quoted above.
Physicists “represent” an unobserved quantum system by a mathematical entity called a wavefunction. I carefully use the word “represent” rather than “describe” because we don't really know what the real relationship is between the wavefunction and the actual world, another embarrassing situation called “the interpretation problem”. Physicists know how to use the wavefunction to correctly calculate (the probability of) all experimental results but they don't really know what the wavefunction means.
So what more does this magnificently useful but utterly mysterious wavefunction say about the Alice and Bob experiment?
First: Quantum theory says that whatever happens is entirely independent of the distance between Alice and Bob. If they are in the same room, as in most practical physics experiments, the results will be exactly the same as if they were ten thousand light years apart, separated by vast interstellar distances.
Second: While unobserved, the wavefunction does not assign any polarization attribute to either Alice's or Bob's photon, but when Alice measures her photon, using a clock direction of her choice, her photon instantly acquires a definite value, AND SO DOES BOB'S PHOTON even though Alice and Bob might be separated by galactic distance. This instantaneous connection, if it is real and not just confined to the theory, violates all the norms of modern physics.
Alice's apparently instant action on Bob's photon has gotta be faster than light (goodbye Einstein) but that's only part of the trouble. This interaction, unlike any we are familiar with in physics, is not diminished by distance. Furthermore, this Alice-Bob intimacy is not transmitted by any field we know of-- it just happens. Alice's action on Bob's photon is, in brief, unmitigated, unmediated and immediate.
Physicists label such alleged behavior, as “non-local”, a tame word that conceals their deep intellectual loathing for an unholy abomination, for a deeply unnatural act. In the world of physics, a “non-local interaction¨, if such a thing ever occured, would be a mortal sin against the Holy Ghost. Non-local interactions are, in physicist's minds, comparable to believing in voodoo, which, come to think of it, is alleged by its practitioners to behave somewhat “non-locally” too.
Third: But what about Einstein? If Alice has access to a non-local interaction, can she and Bob exchange signals faster than light using entangled photons? Since quantum theory describes all experiments perfectly, it can easily answer this question. And the answer is NO. No superluminal signaling is possible using entangled photons. What forbids this is the randomness of each individual event which exactly smothers any alleged non-local Alice-Bob connection.
So what did Bell do with this strange situation? He went against Feynman’s warning about trying to tell a story about what's really going on. Bell's Theorem is not about quantum THEORY, not about quantum EXPERIMENTS, but about quantum REALITY.
Bell tried to imagine the most general model of reality that he could think of, using the term “hidden variables” to make his guesses amenable to mathematical calculation. He imagined all the influences that might go into forming Bob's polarization measurement and left out just one: Alice's choice of what to measure. If Alice's choice is allowed to influence Bob's result, that would imply the existence of a real (we're talking about reality here) non-local interaction in Nature.
Using this one assumption, Bell calculated a set of inequalities that the EXPERIMENTAL RESULTS of any local model of reality must satisfy.
Guess what? The results predicted by quantum mechanics do not obey the Bell Inequalities. Therefore REALITY MUST BE NON-LOCAL. Bring out your crosses and holy waters, folks. The witch doctors is loose!
The reception of Bell's remarkable proof, which was published in 1964, in an obscure and rather short-lived journal, was a resounding silence. John Clauser, then a graduate student at Columbia, discovered Bell's Theorem in 1969 and wrote him about the possibility of doing an actual experiment to check whether the quantum predictions were correct. Bell reported that this was the first comment on his paper he had yet received—more than four years after its publication.
You often hear it said that when Albert Einstein published his Special Theory of Relativity, only six people understood it. In truth, there were probably lots more than six. But it is fair to say, that when John Bell published his now famous paper, ONLY SIX PEOPLE CARED. John Clauser was one of them.
For the next part of the story I quote David Kaiser's “How the Hippies Saved Physics” which discusses Clauser's accomplishments in great detail.
“Clauser, a budding experimentalist, realized that Bell's theorem could be amenable to real-world tests in a laboratory. Excited, he told his thesis advisor about his find, only to be rebuffed for wasting their time on such philosophical questions. Soon Clauser would be kicked out of some of the finest offices in physics, from Robert Serber's at Columbia to Richard Feynman's at Caltech. Bowing to these pressures, Clauser pursued a dissertation on a more acceptable topic—radio astronomy and astrophysics—but in the back of his mind he continued to puzzle through how Bell's inequality might be put to the test.”
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John Clauser lecturing at Esalen
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I first met John Clauser in his lab at Berkeley in the early 70s where he had cobbled together an ingenious device to test the Bell Inequalities using the few entangled photons that a mercury-vapor lamp produces. He hoped he would gain fame by showing that, for this particular system, quantum theory was wrong, and Reality was Local, as Einstein would have guessed. He succeeded however in finding that quantum theory was right, which means, according to Bell's Proof, that Reality must be non-local! This world, all that we can see around us, remains stubbornly local, but is undergirded, at least in the case of entangled photons, by a network of instant invisible voodoo-like connections.
I was introduced to Clauser as a member of Elizabeth Rauscher and George Weissman's Fundamental Fysiks Group and marveled at his Rube Goldberg setup for measuring polarized-photon coincidences. (He was using pile-of-plates polarizers, for Gods sake!) In addition to recruiting experimentalist John Clauser, FFG also attracted Henry Pierce Stapp, a Berkeley theorist interested in fundamental questions. All of our later ESNR meetings included Clauser and Stapp as core personnel.
Henry Stapp pushed us to closely examine every assumption that goes into Bell's proof, especially those that seem most self-evident, and Clauser kept us posted on other Bell Inequality tests besides his own that were being planned and carried out around the world.
The title of our Esalen Conference: Esalen Seminars on the Nature of Reality, was neither silly nor pretentious. We really were studying “reality” as physicists might view it, as an attempt to tell a story about what's actually going on behind the wavefunction mystery and the measurement mystery. For our ESNR motto we chose a quote from Goethe's Faust, who was also a passionate seeker of Reality. Attesting to the real strangeness of our quest, Clauser's colleague Abner Shimony dubbed these Bell tests "experimental metaphysics."
Our third Esalen meeting (ESNR #3) in 1982 featured a ceremony sponsored by Charles Brandon, one of the founders of Federal Express, to award both John Bell and John Clauser “The Reality Prize” of $3000 each for their firm establishment through theory and experiment of non-locality as a general feature of the world. Bell's Reality Prize was accepted by French physicist Bernard d'Espagnat since Bell could not be there in person. We assured the participants that this prize was merely the first of many that would be bestowed upon the two of them.
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Reality Prize Announcement: Esalen Catalog
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Unfortunately, John Stewart Bell died in 1990, at the age of 62 of a cerebral hemorrhage.
In 2010, John Clauser, Alain Aspect and Anton Zeilinger were awarded the prestigious (Ricardo) Wolf Prize.
And just last week, the same three men were honored with the 2022 Nobel Prize in Physics.
Hearty congratulations to all three of you, O bold and noble champions of quantum reality!
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Clauser, Zeilinger, Aspect: Physics Nobel Prize 2022: Quanta Magazine
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