Absolutely Random Notings on QM—Part 2: LOL!

I intend to aperiodically update this post whenever I run into the more “interesting” write-ups about QM and/or quantum physicists. Accordingly, I will mention the dates on which I update this post.

I will return back to Heisenberg and Schrodinger in the next part of this series. But in the meanwhile, enjoy the “inaugaral” link below.


1. Post first published on 08 July 2018, 13:28 hrs IST with the following “interesting” write-up:

Wiki on “Fundamental Fysiks [sic] Group”: [^]


A Song I Like:

(English, “Western”): “old turkey buzzard…” from the movie “MacKenna’s Gold”
[I here mostly copy-paste, dear gentlemen, for, while I had enjoyed the song especially during the usual turbulent teens, I have not had the pleasure to locate the source of the same–back then, or ever. Hence relying on the ‘net.[Oh, BTW, it requires another post on the movie itself, though! [Just remind me, that’s all!]]]
Music: Quincy Jones
Lyrics: Freddy Douglass
Singer: Jose Feliciano

 

 

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Absolutely Random Notings on QM—Part 1: Bohr. And, a bad philosophy making its way into physics with his work, and his academic influence

TL;DR: Go—and keep—away.


I am still firming up my opinions. However, there is never a harm in launching yet another series of posts on a personal blog, is there? So here we go…


Quantum Mechanics began with Planck. But there was no theory of quanta in what Planck had offered.

What Planck had done was to postulate only the existence of the quanta of the energy, in the cavity radiation.

Einstein used this idea to predict the heat capacities of solids—a remarkable work, one that remains underappreciated in both text-books as well as popular science books on QM.

The first pretense at a quantum theory proper came from Bohr.


Bohr was thinking not about the cavity radiations, but about the spectra of the radiations emitted or absorbed by gases.

Matter, esp. gases, following Dalton, …, Einstein, and Perin, were made of distinct atoms. The properties of gases—especially the reason why they emitted or absorbed radiation only at certain distinct frequencies, but not at any other frequencies (including those continuous patches of frequencies in between the experimentally evident sharp peaks)—had to be explained in reference to what the atoms themselves were like. There was no other way out—not yet, not given the sound epistemology in physics of those days.

Thinking up a new universe still was not allowed back then in science let alone in physics. One still had to clearly think about explaining what was given in observations, what was in evidence. Effects still had be related back to causes; outward actions still had to be related back to the character/nature of the entities that thus acted.

The actor, unquestionably by now, was the atom. The effects were the discrete spectra. Not much else was known.

Those were the days were when the best hotels and restaurants in Berlin, London, and New York would have horse-driven buggies ushering in the socially important guests. Buggies still was the latest technology back then. Not many people thus ushered in are remembered today. But Bohr is.


If the atom was the actor, and the effects under study were the discrete spectra, then what was needed to be said, in theory, was something regarding the structure of the atom.

If an imagined entity sheer by its material/chemical type doesn’t do it, then it’s the structure—its shape and size—which must do it.

Back then, this still was regarded as one of the cardinal principles of science, unlike the mindless opposition to the science of Homeopathy today, esp. in the UK. But back then, it was known that one important reason that Calvin gets harassed by the school bully was that not just the sheer size of the latter’s matter but also that the structure of the latter was different. In other words: If you consumed alcohol, you simply didn’t take in so many atoms of carbon as in proportion to so many atoms of hydrogen, etc. You took in a structure, a configuration with which these atoms came in.


However, the trouble back then was, none had have the means to see the atoms.

If by structure you mean the geometrical shape and size, or some patterns of density, then clearly, there was no experimental observations pertaining to the same. The only relevant observation available to people back then was what had already been encapsulated in Rutherford’s model, viz., the incontestable idea that the atomic nucleus had to be massive and dense, occupying a very small space as compared to an atom taken as a whole; the electrons had to carry very little mass in comparison. (The contrast of Rutherford’s model of c. 1911 was to the earlier plum cake model by Thomson.)

Bohr would, therefore, have to start with Rutherford’s model of atoms, and invent some new ideas concerning it, and see if his model was consistent with the known results given by spectroscopic observations.

What Bohr offered was a model for the electrons contained in a nuclear atom.


However, even while differing from the Rutherford’s plum-cake model, Bohr’s model emphatically lacked a theory for the nature of the electrons themselves. This part has been kept underappreciated by the textbook authors and science teachers.

In particular, Bohr’s theory had absolutely no clue as to the process according to which the electrons could, and must, jump in between their stable orbits.


The meat of the matter was worse, far worse: Bohr had explicitly prohibited from pursuing any mechanism or explanation concerning the quantum jumps—an idea which he was the first to propose. [I don’t know of any one else originally but independently proposing the same idea.]

Bohr achieved this objective not through any deployment of the best possible levels of scientific reason but out of his philosophic convictions—the convictions of the more irrational kind. The quantum jumps were obviously not observable, according to him, only their effects were. So, strictly speaking, the quantum jumps couldn’t possibly be a part of his theory—plain and simple!

But then, Bohr in his philosophic enthusiasm didn’t stop just there. He went even further—much further. He fully deployed the powers of his explicit reasoning as well as the weight of his seniority in prohibiting the young physicists from even thinking of—let alone ideating or offering—any mechanism for such quantum jumps.

In other words, Bohr took special efforts to keep the young quantum enthusiasts absolutely and in principle clueless, as far as his quantum jumps were concerned.


Bohr’s theory, in a sense, was in line with the strictest demands of the philosophy of empiricism. Here is how Bohr’s application of this philosophy went:

  1. This electron—it can be measured!—at this energy level, now!
  2. [May be] The same electron, but this energy level, now!
  3. This energy difference, this frequency. Measured! [Thank you experimental spectroscopists; hats off to you, for, you leave Bohr alone!!]
  4. OK. Now, put the above three into a cohesive “theory.” And, BTW, don’t you ever even try to think about anything else!!

Continuing just a bit on the same lines, Bohr sure would have said (quoting Peikoff’s explanation of the philosophy of empiricism):

  1. [Looking at a tomato] We can only say this much in theory: “This, now, tomato!”
  2. Making a leeway for the most ambitious ones of the ilk: “This *red* tomato!!”

Going by his explicit philosophic convictions, it must have been a height of “speculation” for Bohr to mumble something—anything—about a thing like “orbit.” After all, even by just mentioning a word like “orbit,” Bohr was being absolutely philosophically inconsistent here. Dear reader, observe that the orbit itself never at all was an observable!

Bohr must have in his conscience convulsed at this fact; his own philosophy couldn’t possibly have, strictly speaking, permitted him to accommodate into his theory a non-measurable feature of a non-measurable entity—such as his orbits of his electrons. Only the allure of outwardly producing predictions that matched with the experiment might have quietened his conscience—and that too, temporarily. At least until he got a new stone-building housing an Institute for himself and/or a Physics Nobel, that is.

Possible. With Herr Herr Herr Doktor Doktor Doktor Professor Professors, anything is possible.


It is often remarked that the one curious feature of the Bohr theory was the fact that the stability of the electronic orbits was postulated in it, not explained.

That is, not explained in reference to any known physical principle. The analogy to the solar system indeed was just that: an analogy. It was not a reference to an established physical principle.

However, the basically marvelous feature of the Bohr theory was not that the orbits were stable (in violation of the known laws of electrodynamics). It was: there at all were any orbits in it, even if no experiment had ever given any evidence for the continuously or discontinuously subsequent positions electrons within an atom or of their motions.

So much for originator of the cult of sticking only to the “observables.”


What Sommerfeld did was to add footnotes to Bohr’s work.

Sommerfeld did this work admirably well.

However, what this instance in the history of physics clearly demonstrates is yet another principle from the epistemology of physics: how a man of otherwise enormous mathematical abilities and training (and an academically influential position, I might add), but having evidently no remarkable capacity for a very novel, breakthrough kind of conceptual thinking, just cannot but fall short of making any lasting contributions to physics.

“Math” by itself simply isn’t enough for physics.

What came to be known as the old quantum theory, thus, faced an impasse.

Under Bohr’s (and philosophers’) loving tutorship, the situation continued for a long time—for more than a decade!


A Song I Like:

(Marathi) “sakhi ga murali mohan mohi manaa…”
Music: Hridaynath Mangeshkar
Singer: Asha Bhosale
Lyrics: P. Savalaram


PS: Only typos and animals of the similar ilk remain to be corrected.

 

Is something like a re-discovery of the same thing by the same person possible?

Yes, we continue to remain very busy.


However, in spite of all that busy-ness, in whatever spare time I have [in the evenings, sometimes at nights, why, even on early mornings [which is quite unlike me, come to think of it!]], I cannot help but “think” in a bit “relaxed” [actually, abstract] manner [and by “thinking,” I mean: musing, surmising, etc.] about… about what else but: QM!

So, I’ve been doing that. Sort of like, relaxed distant wonderings about QM…

Idle musings like that are very helpful. But they also carry a certain danger: it is easy to begin to believe your own story, even if the story itself is not being borne by well-established equations (i.e. by physic-al evidence).

But keeping that part aside, and thus coming to the title question: Is it possible that the same person makes the same discovery twice?

It may be difficult to believe so, but I… I seemed to have managed to have pulled precisely such a trick.

Of course, the “discovery” in question is, relatively speaking, only a part of of the whole story, and not the whole story itself. Still, I do think that I had discovered a certain important part of a conclusion about QM a while ago, and then, later on, had completely forgotten about it, and then, in a slow, patient process, I seem now to have worked inch-by-inch to reach precisely the same old conclusion.

In short, I have re-discovered my own (unpublished) conclusion. The original discovery was may be in the first half of this calendar year. (I might have even made a hand-written note about it, I need to look up my hand-written notes.)


Now, about the conclusion itself. … I don’t know how to put it best, but I seem to have reached the conclusion that the postulates of quantum mechanics [^], say as stated by Dirac and von Neumann [^], have been conceptualized inconsistently.

Please note the issue and the statement I am making, carefully. As you know, more than 9 interpretations of QM [^][^][^] have been acknowledged right in the mainstream studies of QM [read: University courses] themselves. Yet, none of these interpretations, as far as I know, goes on to actually challenge the quantum mechanical formalism itself. They all do accept the postulates just as presented (say by Dirac and von Neumann, the two “mathematicians” among the physicists).

Coming to me, my positions: I, too, used to say exactly the same thing. I used to say that I agree with the quantum postulates themselves. My position was that the conceptual aspects of the theory—at least all of them— are missing, and so, these need to be supplied, and if the need be, these also need to be expanded.

But, as far as the postulates themselves go, mine used to be the same position as that in the mainstream.

Until this morning.

Then, this morning, I came to realize that I have “re-discovered,” (i.e. independently discovered for the second time), that I actually should not be buying into the quantum postulates just as stated; that I should be saying that there are theoretical/conceptual errors/misconceptions/misrepresentations woven-in right in the very process of formalization which produced these postulates.

Since I think that I should be saying so, consider that, with this blog post, I have said so.


Just one more thing: the above doesn’t mean that I don’t accept Schrodinger’s equation. I do. In fact, I now seem to embrace Schrodinger’s equation with even more enthusiasm than I have ever done before. I think it’s a very ingenious and a very beautiful equation.


A Song I Like:

(Hindi) “tum jo hue mere humsafar”
Music: O. P. Nayyar
Singers: Geeta Dutt and Mohammad Rafi
Lyrics: Majrooh Sultanpuri


Update on 2017.10.14 23:57 IST: Streamlined a bit, as usual.

 

“Measure for Measure”—a pop-sci video on QM

This post is about a video on QM for the layman. The title of the video is: “Measure for Measure: Quantum Physics and Reality” [^]. It is also available on YouTube, here [^].

I don’t recall precisely where on the ‘net I saw the video being mentioned. Anyway, even though its running time is 01:38:43 (i.e. 1 hour, 38 minutes, making it something like a full-length feature film), I still went ahead, downloaded it and watched it in full. (Yes, I am that interested in QM!)

The video was shot live at an event called “World Science Festival.” I didn’t know about it beforehand, but here is the Wiki on the festival [^], and here is the organizer’s site [^].

The event in the video is something like a panel discussion done on stage, in front of a live audience, by four professors of physics/philosophy. … Actually five, including the moderator.

Brian Greene of Columbia [^] is the moderator. (Apparently, he co-founded the World Science Festival.) The discussion panel itself consists of: (i) David Albert of Columbia [^]. He speaks like a philosopher but seems inclined towards a specific speculative theory of QM, viz. the GRW theory. (He has that peculiar, nasal, New York accent… Reminds you of Dr. Harry Binswanger—I mean, by the accent.) (ii) Sheldon Goldstein of Rutgers [^]. He is a Bohmian, out and out. (iii) Sean Carroll of CalTech [^]. At least in the branch of the infinity of the universes in which this video unfolds, he acts 100% deterministically as an Everettian. (iv) Ruediger Schack of Royal Holloway (the spelling is correct) [^]. I perceive him as a QBist; guess you would, too.

Though the video is something like a panel discussion, it does not begin right away with dudes sitting on chairs and talking to each other. Even before the panel itself assembles on the stage, there is a racy introduction to the quantum riddles, mainly on the wave-particle duality, presented by the moderator himself. (Prof. Greene would easily make for a competent TV evangelist.) This part runs for some 20 minutes or so. Then, even once the panel discussion is in progress, it is sometimes interwoven with a few short visualizations/animations that try to convey the essential ideas of each of the above viewpoints.

I of course don’t agree with any one of these approaches—but then, that is an entirely different story.

Coming back to the video, yes, I do want to recommend it to you. The individual presentations as well as the panel discussions (and comments) are done pretty well, in an engaging and informal way. I did enjoy watching it.


The parts which I perhaps appreciated the most were (i) the comment (near the end) by David Albert, between 01:24:19–01:28:02, esp. near 1:27:20 (“small potatoes”) and, (ii) soon later, another question by Brian Greene and another answer by David Albert, between 01:33:26–01:34:30.

In this second comment, David Albert notes that “the serious discussions of [the foundational issues of QM] … only got started 20 years ago,” even though the questions themselves do go back to about 100 years ago.

That is so true.

The video was recorded recently. About 20 years ago means: from about mid-1990s onwards. Thus, it is only from mid-1990s, Albert observes, that the research atmosphere concerning the foundational issues of QM has changed—he means for the better. I think that is true. Very true.

For instance, when I was in UAB (1990–93), the resistance to attempting even just a small variation to the entrenched mainstream view (which means, the Copenhagen interpretation (CI for short)) was so enormous and all pervading, I mean even in the US/Europe, that I was dead sure that a graduate student like me would never be able to get his nascent ideas on QM published, ever. It therefore came as a big (and a very joyous) surprise to me when my papers on QM actually got accepted (in 2005). … Yes, the attitudes of physicists have changed. Anyway, my point here is, the mainstream view used to be so entrenched back then—just about 20 years ago. The Copenhagen interpretation still was the ruling dogma, those days. Therefore, that remark by Prof. Albert does carry some definite truth.


Prof. Albert’s observation also prompts me to pose a question to you.

What could be the broad social, cultural, technological, economic, or philosophic reasons behind the fact that people (researchers, graduate students) these days don’t feel the same kind of pressure in pursuing new ideas in the field of Foundations of QM? Is the relatively greater ease of publishing papers in foundations of QM, in your opinion, an indication of some negative trends in the culture? Does it show a lowering of the editorial standards? Or is there something positive about this change? Why has it become easier to discuss foundations of QM? What do you think?

I do have my own guess about it, and I would sure like to share it with you. But before I do that, I would very much like to hear from you.

Any guesses? What could be the reason(s) why the serious discussions on foundations of QM might have begun to occur much more freely only after mid-1990s—even though the questions had been raised as early as in 1920s (or earlier)?

Over to you.


Greetings in advance for the Republic Day. I [^] am still jobless.


[E&OE]