Wednesday, February 21, 2018

critical review of a prominent theory of quantum mechanics and cosmic consciousness

I have run across lots of people excited by mainstream quantum philosophy. Here is my evaluatoio of part of that discussion:
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In essence, these views of quantum theory and cosmic consciousness attributed to Stapp do constitute a religion. (Though I view quantum theory and cosmic consciousness as both real, I define "cosmic consciousness" in a very different way from the formal assumption being made here.) Humans in general have a strange tendency not to question the details of their particular religion, and to strive to be orthodox, even as they are surrounded by billions of people who adhere to very different religions contradicting their own. Sanity DEMANDS that we actually pay attention to the obvious uncertainties,
such as the concrete realities of what quantum theory actually IS.

For some people quantum theory has somehow morphed in their minds to being a holy relic, like a golden cow or a green jade goat. The faithful would consider it blasphemy to ask what connection that golden cow or green goat would have to those awful mundane cows and goats they actually see on the streets... or perhaps they make sure never to visit such profane streets. Why bother to learn anything real about real cows when you have a purified golden one to worship and not question, and you have a whole nation or tribe of orthodox believers  proud to wall themselves off from the profane masses beyond the walls? There are ever so many instances of such thinking on this planet.

For quantum theory in particular... the validity of something called "quantum mechanics" (a term used in a very loose way by many people) was fully established in physics because of a SPECIFIC EXPERIMENT, the "Bell's Theorem" experiment, performed and based on an experiment by Clauser, Holt, Shimony and Horn (CHSH), popularized (with a bit of spin) by the classic book The Speakable and Unspeakable in Quantum Mechanics, by J.S. Bell.
What we really know about the philosophical implications of QM in general... is really just what we know from that experiment.  (OK, some of us do know a bit more which is also fundamental based on more technical experiments, none of which I see reflected in any of the discussions here.) 

We don't know ANYTHING from that experiment which says ANYTHING about ghosts or even consciousness, any more than classical experiments already did. Sure, humans (other than the experimenter) don't know about the results until humans write and read papers -- but that was already true in classical physics. There is nothing quantum about that. The ACTUAL predictions are based on a straightforward mathematical calculation, given in detail in Horn's thesis, described in the review by Clauser and Shimony themselves, and re-presented equivalently and more elegantly both in the standard text by Scully and Zubairy and in https://arxiv.org/abs/1309.6168. Given a model of what polarizers do to density matrices, and how density matrices interact with polarizers, that is enough to predict the double counting rates ACTUALLY OBSERVED in that experiment. There are no ghosts or conscious observers 
used or assumed in that calculation, and the success of that calculation is all we actually KNOW. Adding an "interpretation" beyond that is what people once did with classical mechanics as well, as in "if a bird sings in the forest and no human hears it, is the bird really there?" THERE IS NO EVIDENCE for anything beyond the actual inhuman, unconscious models actually used to predict the experiment. If you decide you want to INTERPRET 
the success of your coffee maker as the ultimate consequence of the will of a purple hippopotamus in your basement, and you religiously keep people out of your sacred basement, then we can't prove that the hippopotamus is not there, but if the coffee maker works perfectly well AS IT IS without intervention...

Why would anyone ever speculate about ghosts in the experiment? Well, to begin with, lots of people love ghosts. It is just like the right wingers on reddit, who strive hard for... confirmation bias. If a modern group of quantum philosophers maintain turf walled off from folks who do hard experiments in photonics and electronics, each can be happy just staying away from the other; no contamination of the golden cow from real ones, and real farmers quite happy to stay away from the golden ones in our society. 

But there is another aspect. The simple crude summary of Von Neumann's "process 1 and process 2" did reflect the reality of serious experiment-oriented understanding at that time, and now (with minor caveats). Process 1, the measurement process, has in fact been modeled by quick and dirty models of polarizers and detectors. One may ask: "WHY do we see a projection of density matrices to a mixture of eigenvectors when light hits a polarizer or a detector?" It was convenient to use a separate model for such macroscopic objects in quantum experiments, and treat those models as sancrosanct, because it simplified the calculations. Talk about ghosts was basically just an excuse for using one type of mathematical model for one stage of the process, and a different set at another. But serious physicists have long asked: WHY the dichotomy? WHY can't we just model the polarizers and detectors by the same kind of (time-symmetric) model we use in "process 2," the Schrodinger equation itself? WHY can't we follow Occam's Razor by using "Process 2" ONLY to predict experiments like CHSH?"

In fact, WE NOW CAN. We don't need a separate process 1 as an axiom. That's the real importance of  https://arxiv.org/abs/1309.6168 and the followons.

Back in Von Neumann's day, we simply did not have solid models of solid state physics good enough to bridge the gap from the Schrodinger equation (and even classical solid state physics, as in photonics) to the operation of polarizers (and detectors, not a problem) in CHSH. Now we do. New models of the polarizer which maintain the time-symmetry of the Schrodinger equation fit the CHSH experiment just as well as the old simpler ad hoc models did. We don't need process 1. To test whether process 1 exists at all, we need to do the crucial experiments capable of saying which models of the polarizers and of thermal light sources) are actually correct. If we do those experiments, and they support the old ad hoc models, the followers of the purple hippopotamus 
would feel vindicated. If they truly believe din their theory, and in the scientific method, they would push hard for the experiments which they think would verify the existence of their purple hippopotamus. 

This situation reminds me of an NSF review panel which I OBSERVED (not managed). It reminds me of the guy who said "We should not fund this proposal, because it is too high-risk." When another guy asked: "What is the risk?", he replied "The risk is that it could disprove my theory." That is a personally rational answer, if he did not really believe his theory was true, and if his value system placed great weight on his personal standing and none on the truth. 
What a combination!!! But it seems he was not alone. His behavior raised questions not just about funding the specific proposal, but about funding that entire community.

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Later reflections:

I can't help wondering.. The reality of quantum measurement and such is all essentially on based on something you can see on a billiards table... something which I HAVE seen with mundane eyes looking at a billiard table. 
The most definitive "Bell" experiment was on a table in Maryland, with a laser on it, and little "game pieces" and a detector connected to a PC. 

How can people stare at such a straightforward physical thing and imagine so many ghosts and spirits and higher order psychological complexities?

Is this the modern equivalent of the old meditation experiment of staring into a fire and letting thoughts (some veridical, some fantasy) pour into the mind? 

Of course, fires were once a mystery to science. Or the science of prescience? Whatever. And even now, one can actually try to play with an actual candle flame, much as George plays with things that can rotate. But... Dean Radin is the only one I know of who has asked people to play with a "Bell" experiment, as an actual PK toy; it has the advantage of being well instrumented, but is it really easier for humans to engage with it than to engage with a fire or a mobile? Or is that question itself too fuzzy to really answer?

Stan talks about the standard X number of philosophical interpretations of QM, which belong to a particular subset of philosophers. While I don't like the overstress on Standard Allowed Ideas, I have to admit that in the world of real empirical science, int he ultraempirical and practical world of photonics, there really is just one standard way to predict (and thus understand) the statistics we observe in the modern, precise "Bell" experiment, the experiment which is the very paradigm of entanglement. There is a Bell state pure wave function coming out of the  nonlinear crystal -- a rank one density matrix. Each time the light hits a polarizer (first on the left, then on the right, or vice-versa), the polarizer converts that pure state to a mixed state. Then when it hits a detector, it does the same thing again. The computer which records the event is observed to have a certain probability of recording a detection on the left at the same time as detection on the right, to within a few nanoseconds. (Or picoseconds? I forget, but they always say in the papers.) The correct quantum prediction is simply based on assuming that the probability of detection equals the square norm of the density matrix at the location of the detector. That's it. That works. Just math, no ghosts. No humans necessary, except to notice what the computer prints out the next day -- and that much was already needed for humans in experiments before quantum mechanics appeared. (OK, PCs are newer than quantum mechanics, but no one here is worshipping THEM at least!) 

I am not alleging that ghosts do not exist. But if they do exist, chasing after imaginary ones would actually prevent you from locating real ones or learning anything about them.

Mystical meditations on a billiards table....
and the distinction between real mysticism and willful mystification. 

Best of luck,

    Paul

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P.S. Actually, since I am into first person direct observation, I am grateful to have had a chance to see more than one quantum optics lab.

I never actually saw the very first CHSH laboratory, the workplace of my classmate Richard Holt, but he certainly showed me papers and talked about it a lot over tea at Harkness Commons at Harvard.

Possibly the first one I saw was at UMBC, just outside Baltimore Beltway, in a visit to Yanhua Shih, whose group did the first high precision Down Conversion (SPDC TYpe II) "Bell" experiment. I used to say "it all fit on a ping pong table," but my wife says "Billiard" is more accurate; it was a simple but solid and stable apparatus. 
A huge amount of art and thought went into keeping it relatively simple and clear. In great part the secret of their unique initial success was making use of the work of a guy named Klyshko, who was very serious but even less standardized in his thinking than I am; he had a rough and ready quantitative model which was easier to use than the standard calculations, and actually more consistent with MQED than the standard ones are. 

By contrast, Preskill's Lab at CalTech looked more like an archeological dig, generations of students resulting in sprawl and complexity with more layers and mysteries than the excavation of Troy. 

At Tsingua (already three months ago) I think it actually WAS a
ping pong table, in a room somewhat protected from stray disturbances - smaller than than Shih's table, and much more cluttered, albeit not quite archeological. I posted a photo of it on Facebook when I came back. When I saw it, it had be be a bit complicated, because they were in the process of converting from a kind of third generation Bell-type experiment to a new experiment requested by authorities wanting something more practical.  

Third generation? The classic experiment used "Bell states," states of two photons entangled. Second generation, called GHz, entangles three photons together. Bell's book shows that you can't send information faster than light with a Bell state, but I claim that you CAN with proper use of a GHz state. On this pingpong table, they did the work for a paper by Wilczek, Hou and others easy to find in arxiv, where they bounced a single photon through time in a way which entailed triple entanglement (GHz) with instances of itself, used to probe the idea that there really are parallel "histories" out there. Basically, parallel "histories" is another way to talk about the parallel "universes" of the multiverse theory of Everett, Wheeler and Deutsch. Yes, they verified that theory (or at least the "crazy" part of it), but most serious quantum optickers just yawned, since we already knew it. 


1 comment:

  1. Life is just a series of "flat files" we view from the inside.

    "All our Yesterdays," Star Trek (TOS)

    ReplyDelete