Friday, December 29, 2017

Objective reality IS a major part of mainstream physics

Popular culture -- and even conventional wisdom in general science -- often lags behind the real cutting edge of what is being learned by the best mainstream hard core science.
This post addresses an important example: the issue of whether objective reality exists.
Some people on the Vedanta list recently quoted a famous book by d'Espagnat, repeating the old idea from the 1920's that quantum mechanics proves that objective reality does not exist. I explained why not, and, more important, reviewed what needs to be done next to understand reality better:

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On Fri, Dec 29, 2017 at 11:19 AM, Paul Werbos <paul.werbos@gmail.com> wrote:
Do physicists believe in objective reality or not? The exchanges here are somewhat discouraging to me, because the true story is very well documented and I have given solid citations on the issue before this. On the other hand, ... has shown enough insight that I may add some new details here today.

People have quoted a book by d'Espagnat, to deduce that objective reality is no longer a mainstream option in physics. Frankly, the comments did not encourage me to see what his recent writings may be, but I certainly remember a very important canonical survey book from d'Espagnat on Bell's Theorem experiments and what they tell us. I remember reading large parts of it in about 1975, in the Harvard Coop bookstore, and being very impressed that he had the integrity and ability to report much of the truth about the very first Bell experiment, by Richard Holt at Harvard, which actually disagreed BOTH with quantum mechanics AND with the assumptions Einstein had used in analyzing the EPR experiment (the original idea for this experiment).

   (Comment: I had tea with Richard at Harkness Common on the day he got those first results, and will never forget that day. But a later review by Clauser and Shimony also notes that the first experiment did not "agree with quantum mechanics." Or with the VERSION of quantum mechanics they assumed?)
Espagnat has a long resume, but no real scientist would tell us we should automatically defer to a claim about physics based on a quotation from one person long ago. (Hey, Newton had a nice resume, and people have quoted him on odd things). I did say, in my previous posts, that many mainstream versions of quantum field theory do perpetuate the old idea  that objective reality does not exist, but many do not. (My point is that objective reality IS a major mainstream option, explained in detail below)

If we have to have an idiotic war of resumes and egos, let's start with scholar.google.com. I am a bit surprised that d'Espagnat's top citation seems to be 38. That is lower than I would have expected, so maybe someone can find a more positive indicator? But for David Deutsch (search on Deutsch author, with word "quantum"), he gets over 5000 citations for his top paper. (I get 4700, but that's for the Chinese version of mathematics underlying neural networks.) More important, Deutsch was not just an anthology writer, but the creator of a whole new branch of empirical quantum physics:
https://www.ictp.it/about-ictp/prizes-awards/the-dirac-medal/the-medallists/dirac-medallists-2017.aspx
He is the guy who developed the version of quantum computing which animates almost all the work in the West today. HE DEVELOPED it by paying serious attention to the respected but obscure theory of Everett and Wheeler, who showed that quantum field theory is 100% consistent with the idea of objective reality, if we assume that the cosmos or "multiverse" we live in has infinite dimensions. That concept of objective reality, and David Deutsch's work on it, is certainly as mainstream as one can get. Quantum computing in the paradigm of David Deutsch is a highly empirical and real branch of physics, far more consistent with science as defined by Kuhn and Bacon than is speculative stuff like superstring theory, let alone... some of what we have seen here.
Once again, I highly recommend David Deutsch's book The Fabric of Reality for a highly credible version of objective reality in well-validated mainstream physics today.
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So why would anyone pooh-pooh that? I don't know. There is a lot of destructive factionalism in all branches of science these days (and all branches of religion as well). Some would perhaps pooh-pooh Deutsch's version of quantum field theory, and pretend it does not even exist. (I have certainly seem computer scientists behave that way, pretending ignorance of algorithms they don't own.) But perhaps in this case, it was just a matter of context, leading him to interpret "objective reality" with EINSTEIN'S version of objective reality, in which we assume the cosmos is finite-dimensional, maybe just 3+1-D curved Minkowski space. 

Certainly the concept of objective reality in 3+1 dimensions is far more controversial and marginal in mainstream physics today than is the concept of multiverse reality.
So then, I can imagine a True Believer (Vedantist or Marxist, whatever) asking: "So which do YOU believe? You must believe SOMETHING. If not, you are a confessed ignorant wimp, beneath the attention of all real people."

Sorry. I believe in Sanity or Zhengqi much more than I believe in any specific theories or ontologies about the cosmos or the absolute. Part of Sanity is being honest to oneself about one's many areas of ignorance. In first person science, as in third person science, the folks who feel obligated to pick an opinion the way they pick dress-up clothing to appeal to their vanity simple WEAKEN themselves, their ability to learn, and their credibility in the eyes of those who have attained a moderate degree of sanity.
I do adhere to the GENERAL notion of objective reality, for reasons I should not review again here. (e.g. at www.werbos.com/Mind_in_Time.pdf, an IFNA journal paper which only halfway made it to google scholar.)

I do not believe that physicists have a duty to PICK the TRUE theory as we know it today. Rather, the first duty of physics is to LEARN BASIC THINGS WHICH IT DOES NOT YET KNOW. That requires a multipronged approach. The the area of quantum technology, I would advocate greater use and testing of a specific MULTIVERSE theory, MQED, compared with KQED (Deutsch's version  of QED). That work would simply ASSUME multiverse realism, and not waste time on various fantasy alternatives popular among philosophers or even abstract alternatives popular among mathematicians.

On the other hand, on a parallel prong, I am also interested in work on three levels of possible deeper theory, aimed at theories which "approximate" MQED or which MQED could be seen as an approximation of. And yes, for the deepest of these, I have IDEAS for how to construct a credible PDE model fulfilling Einsteinian realism. Like 'tHooft, I recognize that no such specific theory exists as yet on earth. I am ever so sad that 'tHooft shares the goal,  but imposes restrictions on himself and others which make it logically impossible to attain the goal. I view him as someone like the person who wants to drive to a far place in his/her car, but is just too fussy to replace an old spark plug without which the journey is impossible. And is so fussy he would not even let anyone else make the attempt. (Google typed "fuzzy", not fussy. OK, it is right. And it knows I type "fuzzy" more often than I type "fussy.") 

But... I have thought about that experiment which Holt told me about, which d'Espagnat mentioned, which is a mystery to this day. Just this week, I have seen some leads which POSSIBLY, just possibly, might have some explanation. With a very noisy thermal partially coherent source of entangled photons (a mercury vapor lamp) AND calcite type polarizers... DO calcite polarizers (and similar beamsplitters) transform n-occupancy photon states differently from polaroid or sunglasses type polarizers, either with or without allowance for the time symmetry of all such passive objects? I don't know, but it would be really neat if explanation could be found not only for the "best" experiments but for all of them. Even neater if anyone else on earth would be willing and able to learn that humble simple KQED/MQED math. Seriously. Having just one 70-year-old retiree on the task is not a good situation, especially when I have other responsibilities.
If just one of you can really catch up with such things, it would be exciting and important. 

Happy New Year..

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