Why is the research on the foundations of QM necessary?

Why is the research on the foundations of QM necessary? … This post is meant to hold together some useful links touching on various aspects of this question.


Sabine Hossenfelder:

See her blog post: “Good Problems in the Foundations of Physics” [^]. Go through the entirety of the first half of the post, and then make sure to check out the paragraph of the title “The Measurement Problem” from her list.

Not to be missed: Do check out the comment on this post by Peter Shor, here [^], and Hossenfelder’s reply to it, here [^]. … If you are familiar with the outline of my approach [^], then it would be very easy to see why I must have instantaneously found her answer to be so absolutely wonderful! … Being a reply to a comment, she must have written her reply much on the fly. Even then, she not only correctly points out the fact that the measurement process must be nonlinear in nature, she also mentions that you have to give a “bottom-up” model of the Instrument. …Wow! Simply, wow!!


Lee Smolin:

Here is one of the most lucid and essence-capturing accounts concerning this topic that I have ever run into [^]. Smolin wrote it in response to the Edge Question, 2013 edition. It wonderfully captures the very essence of the confusions which were created and / or faced by all the mainstream physicists of the past—the confusions which none of them could get rid of, with the list including even such Nobel-laureates as Bohr, Einstein, Heisenberg, Pauli, de Broglie, Schrodinger, Dirac, and others. [Yes, in case you read the names too rapidly: this list does include Einstein too!]


Sean Carroll:

He explains at his blog how a lack of good answers on the foundational issues in QM leads to “the most embarrassing graph in modern physics” [^]. This post was further discussed in several other posts in the blogosphere. The survey paper which prompted Carroll’s post can be found at arXiv, here [^]. Check out the concept maps given in the paper, too. Phillip Ball’s coverage in the Nature News of this same paper can be found here [^].


…What Else?:

What else but the Wiki!… See here [^], and then, also here [^].


OK. This all should make for an adequate response, at least for the time being, to those physicists (or physics professors) who tend to think that the foundational issues does not make for “real” physics, that it is a non-issue. … However, for obvious reasons, this post will also remain permanently under updates…

 

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The rule of omitting the self-field in calculations—and whether potentials have an objective existence or not

There was an issue concerning the strictly classical, non-relativistic electricity which I was (once again) confronted with, during my continuing preoccupation with quantum mechanics.

Actually, a small part of this issue had occurred to me earlier too, and I had worked through it back then.

However, the overall issue had never occurred to me with as much of scope, generality and force as it did last evening. And I could not immediately resolve it. So, for a while, especially last night, I unexpectedly found myself to have become very confused, even discouraged.

Then, this morning, after a good night’s rest, everything became clear right while sipping my morning cup of tea. Things came together literally within a span of just a few minutes. I want to share the issue and its resolution with you.

The question in question (!) is the following.


Consider 2 (or N) number of point-charges, say electrons. Each electron sets up an electrostatic (Coulombic) potential everywhere in space, for the other electrons to “feel”.

As you know, the potential set up by the i-th electron is:
V_i(\vec{r}_i, \vec{r}) = \dfrac{1}{4 \pi \epsilon_0} \dfrac{Q_i}{|\vec{r} - \vec{r}_i|}
where \vec{r}_i is the position vector of the i-th electron, \vec{r} is any arbitrary point in space, and Q_i is the charge of the i-th electron.

The potential energy associated with some other (j-th) electron being at the position \vec{r}_j (i.e. the energy that the system acquires in bringing the two electrons from \infty to their respective positions some finite distance apart), is then given as:
U_{ij}(\vec{r}_i, \vec{r}_j) = \dfrac{1}{4 \pi \epsilon_0} \dfrac{Q_i\,Q_j}{|\vec{r}_j - \vec{r}_i|}

The notation followed here is the following: In U_{ij}, the potential field is produced by the i-th electron, and the work is done by the j-th electron against the i-th electron.

Symmetrically, the potential energy for this configuration can also be expressed as:
U_{ji}(\vec{r}_j, \vec{r}_i) = \dfrac{1}{4 \pi \epsilon_0} \dfrac{Q_j\,Q_i}{|\vec{r}_i - \vec{r}_j|}

If a system has only two charges, then its total potential energy U can be expressed either as U_{ji} or as U_{ij}. Thus,
U = U_{ji} = U_{ij}

Similarly, for any pair of charges in an N-particle system, too. Therefore, the total energy of an N-particle system is given as:
U = \sum\limits_{i}^{N} \sum\limits_{j = i+1}^{N} U_{ij}

The issue now is this: Can we say that the total potential energy U has an objective existence in the physical world? Or is it just a device of calculations that we have invented, just a concept from maths that has no meaningful physical counterpart?

(A side remark: Energy may perhaps exist as an attribute or property of something else, and not necessarily as a separate physical object by itself. However, existence as an attribute still is an objective existence.)

The reason to raise this doubt is the following.


When calculating the motion of the i-th charge, we consider only the potentials V_j produced by the other charges, not the potential produced by the given charge V_i itself.

Now, if the potential produced by the given charge (V_i) also exists at every point in space, then why does it not enter the calculations? How does its physical efficacy get evaporated away? And, symmetrically: The motion of the j-th charge occurs as if V_j had physically evaporated away.

The issue generalizes in a straight-forward manner. If there are N number of charges, then for calculating the motion of a given i-th charge, the potential fields of all other charges are considered operative. But not its own field.

How can motion become sensitive to only a part of the total potential energy existing at a point even if the other part also exists at the same point? That is the question.


This circumstance seems to indicate as if there is subjectivity built deep into the very fabric of classical mechanics. It is as if the universe just knows what a subject is going to calculate, and accordingly, it just makes the corresponding field mystically go away. The universe—the physical universe—acts as if it were changing in response to what we choose to do in our mind. Mind you, the universe seems to change in response to not just our observations (as in QM), but even as we merely proceed to do calculations. How does that come to happen?… May be the whole physical universe exists only in our imagination?

Got the point?


No, my confusion was not as pathetic as that in the previous paragraph. But I still found myself being confused about how to account for the fact that an electron’s own field does not enter the calculations.

But it was not all. A non-clarity on this issue also meant that there was another confusing issue which also raised its head. This secondary issue arises out of the fact that the Coulombic potential set up by any point-charge is singular in nature (or at least approximately so).

If the electron is a point-particle and if its own potential “is” \infty at its position, then why does it at all get influenced by the finite potential of any other charge? That is the question.

Notice, the second issue is most acute when the potentials in question are singular in nature. But even if you arbitrarily remove the singularity by declaring (say by fiat) a finite size for the electron, thereby making its own field only finitely large (and not infinite), the above-mentioned issue still remains. So long as its own field is finite but much, much larger than the potential of any other charge, the effects due to the other charges should become comparatively less significant, perhaps even negligibly small. Why does this not happen? Why does the rule instead go exactly the other way around, and makes those much smaller effects due to other charges count, but not the self-field of the very electron in question?


While thinking about QM, there was a certain point where this entire gamut of issues became important—whether the potential has an objective existence or not, the rule of omitting the self-field while calculating motions of particles, the singular potential, etc.

The specific issue I was trying to think through was: two interacting particles (e.g. the two electrons in the helium atom). It was while thinking on this problem that this problem occurred to me. And then, it also led me to wonder: what if some intellectual goon in the guise of a physicist comes along, and says that my proposal isn’t valid because there is this element of subjectivity to it? This thought occurred to me with all its force only last night. (Or so I think.) And I could not recall seeing a ready-made answer in a text-book or so. Nor could I figure it out immediately, at night, after a whole day’s work. And as I failed to resolve the anticipated objection, I progressively got more and more confused last night, even discouraged.

However, this morning, it all got resolved in a jiffy.


Would you like to give it a try? Why is it that while calculating the motion of the i-th charge, you consider the potentials set up by all the rest of the charges, but not its own potential field? Why this rule? Get this part right, and all the philosophical humbug mentioned earlier just evaporates away too.

I would wait for a couple of days or so before coming back and providing you with the answer I found. May be I will write another post about it.


Update on 2019.03.16 20:14 IST: Corrected the statement concerning the total energy of a two-electron system. Also simplified the further discussion by couching it preferably in terms of potentials rather than energies (as in the first published version), because a Coulombic potential always remains anchored in the given charge—it doesn’t additionally depend on the other charges the way energy does. Modified the notation to reflect the emphasis on the potentials rather than energy.


A song I like:

[What else? [… see the songs section in the last post.]]
(Hindi) “woh dil kahaan se laaoon…”
Singer: Lata Mangeshkar
Music: Ravi
Lyrics: Rajinder Kishen


A bit of a conjecture as to why Ravi’s songs tend to be so hummable, of a certain simplicity, especially, almost always based on a very simple rhythm. My conjecture is that because Ravi grew up in an atmosphere of “bhajan”-singing.

Observe that it is in the very nature of music that it puts your mind into an abstract frame of mind. Observe any singer, especially the non-professional ones (or the ones who are not very highly experienced in controlling their body-language while singing, as happens to singers who participate in college events or talent shows).

When they sing, their eyes seem to roll in a very peculiar manner. It seems random but it isn’t. It’s as if the eyes involuntarily get set in the motions of searching for something definite to be found somewhere, as if the thing to be found would be in the concrete physical space outside, but within a split-second, the eyes again move as if the person has realized that nothing corresponding is to be found in the world out there. That’s why the eyes “roll away.” The same thing goes on repeating, as the singer passes over various words, points of pauses, nuances, or musical phrases.

The involuntary motions of the eyes of the singer provide a window into his experience of music. It’s as if his consciousness was again and again going on registering a sequence of two very fleeting experiences: (i) a search for something in the outside world corresponding to an inner experience felt in the present, and immediately later, (ii) a realization (and therefore the turning away of the eyes from an initially picked up tentative direction) that nothing in the outside world would match what was being searched for.

The experience of music necessarily makes you realize the abstractness of itself. It tends to make you realize that the root-referents of your musical experience lie not in a specific object or phenomenon in the physical world, but in the inner realm, that of your own emotions, judgments, self-reflections, etc.

This nature of music makes it ideally suited to let you turn your attention away from the outside world, and has the capacity or potential to induce a kind of a quiet self-reflection in you.

But the switch from the experience of frustrated searches into the outside world to a quiet self-reflection within oneself is not the only option available here. Music can also induce in you a transitioning from those unfulfilled searches to a frantic kind of an activity: screams, frantic shouting, random gyrations, and what not. In evidence, observe any piece of modern American / Western pop-music.

However, when done right, music can also induce a state of self-reflection, and by evoking certain kind of emotions, it can even lead to a sense of orderliness, peace, serenity. To make this part effective, such a music has to be simple enough, and orderly enough. That’s why devotional music in the refined cultural traditions is, as a rule, of a certain kind of simplicity.

The experience of music isn’t the highest possible spiritual experience. But if done right, it can make your transition from the ordinary experience to a deep, profound spiritual experience easy. And doing it right involves certain orderliness, simplicity in all respects: tune, tone, singing style, rhythm, instrumental sections, transitions between phrases, etc.

If you grow up listening to this kind of a music, your own music in your adult years tends to reflect the same qualities. The simplicity of rhythm. The alluringly simple tunes. The “hummability quotient.” (You don’t want to focus on intricate patterns of melody in devotional music; you want it to be so simple that minimal mental exertion is involved in rendering it, so that your mental energy can quietly transition towards your spiritual quest and experiences.) Etc.

I am not saying that the reason Ravi’s music is so great is because he listened his father sing “bhajan”s. If this were true, there would be tens of thousands of music composers having talents comparable to Ravi’s. But the fact is that Ravi was a genius—a self-taught genius, in fact. (He never received any formal training in music ever.) But what I am saying is that if you do have the musical ability, having this kind of a family environment would leave its mark. Definitely.

Of course, this all was just a conjecture. Check it out and see if it holds or not.

… May be I should convert this “note” in a separate post by itself. Would be easier to keep track of it. … Some other time. … I have to work on QM; after all, exactly only half the month remains now. … Bye for now. …


Should I give up on QM?

After further and deeper studies of the Schrodinger formalism, I have now come to understand the exact position from which the physicists must be coming (I mean the couple of physicists with who I discussed the ideas of my new approach, as mentioned here [^])—why they must be raising their objections. I came to really understand their positions only now. Here is how it happened.


I was pursuing finding correspondence between the 3ND configuration space of the Schrodinger formalism on the one hand and the 3D physical space on the other, when I run into this subtle point which made everything look completely different. That point is the following:

Textbooks (or lecture notes, or lecturers) don’t ever highlight this point (in fact, indirectly, they actually obfuscate it), but I came to realize that even in the 1D cases like the QM harmonic oscillator (QHO), the Schrodinger formalism itself remains defined only on an abstract hyperspace—it’s just that in the case of the QHO, this hyperspace happens to be 1D in nature, that’s all.

I came to realize that, even in the simplest 1D case like the QHO the x variable which appears in the Schrodinger equation does not directly refer to the physical space. In case of QHO, it refers to the change in the equilibrium separation between the centers of the two atoms.

Physicists and textbooks don’t mention this point, and in fact, the way they present QM, they make it look as if x is the simple position variable. But in reality, no it is not. It can be made to look like a position variable (and not a change-in-the-interatomic-distance variable) by fixing the coordinate system to one of the two atoms (i.e. by making it a moving or Lagrangian coordinate system). But doing so leads to losing the symmetry in the motion of the two atoms, and more important, it further results in an obfuscation of the real nature of the issue. Mind you, textbook authors are trying to be helpful here. But unwittingly, they end up actually obfuscating the real story.

So, the x variable whose Laplacian you take for the kinetic energy term also does not represent the physical space—not even in the simplest 1D cases like the QHO.


This insight, which I gained only now, has made me realize that I need to rethink through the whole thing once again.

In other words, my understanding of QM turned out to have been faulty—though the fault is much more on the part of the textbook authors (and lecturers) than on the part of someone like me—one who has learnt QM only through self-studies.


One implication of this better understanding now is that the new approach as stated in the Outline document isn’t going to work out. Even if there are a lot of good ideas in it (Only the Coulomb potentials, the specific nonlinearity proposed in the potential energy term, the ideas concerning measurements, etc.), there are several other ideas in that document which are just so weak that I will have to completely revise my entire approach once again.

Can I do that—take up a complete rethinking once again, and still hope to succeed?

Frankly, I don’t know. Not at this point of time anyway.

I still have not given up. But a sense of tiredness has crept in now. It now seems possible—very easily possible—that QM will end up defeating me, too.


But before outright leaving the fight, I would like to give it just one more try. One last try.

So, I have decided that I will “work” on this issue for just a little while more. May be a couple of weeks or so. Say until the month-end (March 2019-end). Unless I make some clearing, some breaththrough, I will not pursue QM beyond this time-frame.

What is going to be my strategy?

The only way an enterprise like mine can work out is if the connection between the 3D world of observations and the hyperspace formalism can be put in some kind of a valid conceptual correspondence. (That is to say, not just the measurement postulate but something deeper than that, something right at the level of the basic conceptual correspondence itself).

The only strategy that I will now pursue (before giving up on QM) is this: The Schrodinger formalism is based on the higher-dimensional configuration space not because a physicist like him would go specifically hunting for a higher-dimensional space, but primarily because the formulation of Schrodinger’s theory is based on the ideas from the energetics program, viz., the Leibniz-Lagrange-Euler-Hamilton program, their line(s) of thought.

The one possible opening I can think of as of today is this: The energetics program necessarily implies hyperspaces. However, at least in the classical mechanics, there always is a 1:1 correspondence between such hyperspaces on the one hand and the 3D space on the other. Why should QM be any different? … As far as I am concerned, all the mystification they effected for QM over all these decades still does not supply any reason to believe that QM should necessarily be very different. After all, QM does make predictions about real world as described in 3D! Why, even the position vectors that go into the potential energy operator \hat{V} are defined only in the 3D space. …

… So, naturally, it seems that I just have to understand the nature of the correspondence between the Lagrangian mechanics and the 3D mechanics better. There must be some opening in there, based on this idea. In fact my suspicion is stronger: If at all there is a real opening to be found, if at all there is any real way to crack this nutty problem, then its key has to be lying somewhere in this correspondence.

So, I have decided to work on seeing if pursuing this line of thought yields something definitive or not. If it doesn’t, right within the next couple of weeks or so, I think I better throw in the towel and declare defeat.


Now, understanding the energetics program better meant opening up once again the books. But given my style, you know, it couldn’t possibly be the maths books—but only the conceptual ones.

So, this morning, I spent some time opening a couple of the movers-and-packers boxes (in which stuff was still lying as I mentioned before [^]), and also made some space in my room (somehow) by shoving the boxes a bit away to open the wall-cupboard, and brought out a few books I wanted to read  / browse through. Here they are.

 

The one shown opened is what I had mentioned as “the energetics book” in the background material document (see this link [^] in this post [^]). I am going to begin my last shot at QM—the understanding of the 3ND3D issue, starting with this book. The others may or may not be helpful, but I wanted to boast that they are just a part of personal library too!

Wish me luck!

(And suggest me a job in Data Science all the same! [Not having a job is the only thing that gets me (really) angry these days—and it does. So there.])


BTW, I really LOL on the Record of 17 off 71. (Just think what happened in 204!)


A song I like:

(Hindi) “O mere dil ke chain…”
Singer: Kishor Kumar
Music: R. D. Burman
Lyrics: Majrooh Sultanpuri


Minor editing to be done and a song to be added, tomorrow. But feel free to read the post right starting today.

Song added on 2019.03.10 12.09 AM IST. Subject to change if I have run it already.

 

 

 

A preliminary document on my fresh new approach to QM

I have uploaded the outline document I had promised as an attachment to a blog post at iMechanica; see here [^]. I will copy-paste the text of that post below:


Hello, World!

Here is a document that jots down, in a brief, point-wise manner, the elements of my new approach to understanding quantum mechanics.

Please note that the writing is very much at a preliminary stage. It is very much a work in progress. However, it does jot down many essential ideas.

I am uploading the document at iMechanica just to have an externally verifiable time-stamp to it. Further versions will also be posted at this thread.

Comments are welcome. However, I may not be able to respond all of them immediately, because (i) I wish to immediately switch over to my studies of Data Science (ii) discussions on QM, especially on its foundations, tend to get meandering very fast.

Best,

–Ajit


It was only yesterday that I had said that preparing this document would take longer, may be a week or so. But soon later, I discarded the idea of revising the existing document (18 pages), and instead tried re-writing a separate summary for it completely afresh. Turns out that starting afresh all over again was a very good idea. Yesterday, I was at about 2 pages, and today, I finished jotting down all the ideas, at least in essence, right within 8 pages (+ 1 page of the reference section).


A song I like:

[It happens to be one of the songs which I first heard roughly around the same time that I got my own bicycle, and the times when I first came across the quantum mechanical riddles—which was during my X–XII standard days. I had liked it immediately—I mean the song. I don’t know why it doesn’t appear frequently enough on people’s lists of their favorites, but it has a very, very fresh feel to it. It anyway is a song of the teenage, of all those naive expectations and unspoiled optimism. Usha Mangeshkar, with her deft, light touch, somehow manages to bring that sense of life, that sense of freshness and confidence, fully alive in this song. The music and the lyrics are neat too… All in all, an absolutely wonderful song. … Perhaps also equally important, it is of great nostalgic value to me, too.

It used to be not easily available. So, let me give you the link to listening and buying it at Gaana.com; it’s song # 9 on this page [^] ]

(Marathi) “haa unaaD awakhaLa waaraa”
Singer: Usha Mangeshkar
Music: Dasharath Pujari
Lyrics: Ram More

 

An intermediate update regarding my intermediate development regarding my new approach regarding QM

Update on 2019.10.02, 17:00 IST

I have completed writing (more like somehow filling in the contents for) the alpha version of the outline document. However, it is not at all readable. So, I am not in a position to be able to distribute it even as a private communication. (Talking besides the black-board is so much easier to do!)

By now, the outline document alone runs into 18 pages (some of the contents being repetitive). The background document has become another 12 pages. Editing 30 pages should take at least about a week or so, if not a little more.

So, no promises, but chances are good that both these documents could get finalized and distributed within the next 7 to 10 days.

In the meanwhile, feel free to look for the other things on this blog, and bye for now.

Update over; original post, below the fold.



0. As mentioned here earlier, I have been in the process of writing a point-by-point outline document on my new approach to quantum mechanics.


1. A certain preliminary version of the outline document was completed on the afternoon of 4th February 2019. It is about 10 pages long, and roughly at a pre-alpha stage. Separately, there also has been an additional document covering some of the background material for understanding QM. (An earlier version of this background document was posted here at this blog few days ago—too bad if you never noticed it—bad, for you, that is.) It too has been under expansion and revision; currently it stands at a total of further 10 pages (i.e in addition to the outline document).


2. As things usually go at such a stage (i.e., in the stages before the alpha), certain mistakes (including some basic conceptual errors too) were noticed even in the main document, but only after it was “carefully” completed. Currently, these are being addressed.


3. In case you are wondering about the nature of the inadvertent errors or lacunae:

Contrary to what many people might be expecting from me:

3.1: First, errors or lacunae were mainly found not regarding my new ideas concerning the measurement postulate, but rather with the more philosophical ideas concerning the quantum-physical ontology!

3.2: Second, perhaps then not very surprisingly, lacunae were also found on the more applied side of the QM postulates, especially regarding the many- particles systems and quantum entanglement.

The nature of the lacunae / errors somehow gives me a confidence that the basic ideas of my new approach themselves should be right!


4. Pre-release versions starting from the (upcoming) alpha version could perhaps be made available to select physicists, as a private communication. …

… Of course, it is a different matter altogether that I think that none would be interested in the same. (Indian and American physicists and others think that way, anyway!)

… But still, if interested, drop me a line, and I will consider having you on the distribution list (which is expected not to carry more than 8–10 people at the most, so as to keep my own email communications and the attendant diversions and confusions down to the minimum so that I myself the jobless could at all handle it).


5. The Release Candidate should get posted at iMechanica, but only for the purposes of securing an external “time-stamp”—not so much for the purposes of discussions. (The focus of iMechanica is obviously different; it’s much more on the classical engineering side—which fact I love.)


6. I will try to finish the alpha by this week-end.

The next milestones until the final release (or even the release candidates) will be decided once the alpha is actually at the hand.


7. I will announce the availability of the alpha at this blog via a separate post.


A song I like:

(Hindi) “teraa meraa pyaar amar, phir bhee mujh ko lagataa hai Dar…”
Singer: Lata Mangeshkar
Music: Shankar-Jaikishan
Lyrics: Shailendra

[No specific order is being implied by the order of the credits. … In other words, I can’t decide on it. Not for this song.]


History:

First written on my private machine: Wednesday 06 February 2019 08:35:32 AM IST
First finalized here: Wednesday 06 February 2019 11:31:05 PM IST

 

 

Would it happen to me, too? …Also, other interesting stories / links

1. Would it happen to me, too?

“My Grandfather Thought He Solved a Cosmic Mystery,”

reports Veronique Greenwood for The Atlantic [^] [h/t the CalTech physicist Sean Carroll’s twitter feed]. The story has the subtitle:

“His career as an eminent physicist was derailed by an obsession. Was he a genius or a crackpot?”

If you visit the URL for this story, the actual HTML page which loads into your browser has another title, similar to the one above:

“Science Is Full of Mavericks Like My Grandfather. But Was His Physics Theory Right?”

Hmmm…. I immediately got interested. After all, I do work also on foundations of quantum mechanics. … “Will it happpen to me, too?” I thought.

At this point, you should really go through Greenwood’s article, and continue reading here only after you have finished reading it.


Any one who has worked on any conceptually new approach would find something in Greenwood’s article that resonates with him.

As to me, well, right at the time that attempts were being made to find examiners for my PhD, my guide (and even I) had heard a lot of people say very similar things as Greenwood now reports: “I don’t understand what you are saying, so please excuse me.” This, when I thought that my argument should be accessible even to an undergraduate in engineering!

And now that I continue working on the foundations of QM, having developed a further, completely new (and more comprehensive) approach, naturally, Greenwood’s article got me thinking: “Would it happen to me, too? Once again? What if it does?”


…Naah, it wouldn’t happen to me—that was my conclusion. Not even if I continue talking about, you know, QM!


But why wouldn’t something similar happen to me? Especially given the fact that a good part of it has already happened to me in the past?

The reason, in essence, is simple.

I am not just a physicist—not primarily, anyway. I am primarily an engineer, a computational modeller. That’s why, things are going to work out in a different way for me.

As to my past experience: Well, I still earned my PhD degree. And with it, the most critical part of the battle is already behind me. There is a lot of resistance to your acceptance before you have a PhD. Things do become a lot easier once you have gone successfully past it. That’s another reason why things are going to work out in a different way now. … Let me explain in detail.


I mean to say, suppose that I have a brand-new approach for resolving all the essential quantum mechanical riddles. [I think I actually do!]

Suppose that I try to arrange for a seminar to be delivered by me to a few physics professors and students, say at an IIT, IISER, or so. [I actually did!]

Suppose that they don’t respond very favorably or very enthusiastically. Suppose they are outright skeptical when I say that in principle, it is possible to think of a classical mechanically functioning analog simulator which essentially exhibits all the essential quantum mechanical features. Suppose that they get stuck right at that point—may be because they honestly and sincerely believe that no classical system can ever simulate the very quantum-ness of QM. And so, short of calling me a crack-pot or so, they just directly (almost sternly) issue the warning that there are a lot of arguments against a classical system reproducing the quantum features. [That’s what has actually happened; that’s what one of the physics professors I contacted wrote back to me.]

Suppose, then, that I send an abstract to an international conference or so. [This too has actually happend, too, recently.]

Suppose that, in the near future, the conference organizers too decline my submission. [In actual reality, I still don’t know anything about the status of my submission. It was in my routine searches that I came across this conference, and noticed that I did have about 4–5 hours’ time to meet the abstracts submissions deadline. I managed to submit my abstract within time. But since then, the conference Web site has not got updated. There is no indication from the organizers as to when the acceptance or rejection of the submitted abstracts would be communicated to the authors. An enquiry email I wrote to the organizers has gone unanswered for more than a week by now. Thus, the matter is still open. But, just for the sake of the argument, suppose that they end up rejecting my abstract. Suppose that’s what actually happens.]

So what?

Since I am not a physicist “proper”, it wouldn’t affect me the way it might have, if I were to be one.

… And, that way, I could even say that I am far too smart to let something like that (I mean some deep disappointment or something like that) happen to me! … No, seriously! Let me show you how.

Suppose that the abstract I sent to an upcoming conference was written in theoretical/conceptual terms. [In actual reality, it was.]

Suppose now that it therefore gets rejected.

So what?

I would simply build a computational model based on my ideas. … Here, remember, I have already begun “talking things” about it [^]. No one has come up with a strong objection so far. (May be because they know the sort of a guy I am.)

So, if my proposed abstract gets rejected, what I would do is to simply go ahead and perform a computer simulation of a classical system of this sort (one which, in turn, simulates the QM phenomena). I might even publish a paper or two about it—putting the whole thing in purely classical terms, so that I manage to get it published. (Before doing that, I might even discuss the technical issues involved on blogs, possibly even at iMechanica!)

After such a paper (ostensibly only on the classical mechanics) gets accepted and published, I will simply write a blog post, either here or at iMechanica, noting how that system actually simulates the so-and-so quantum mechanical feature. … Then, I would perform another simulation—say using DFT. (And it is mainly for DFT that I would need help from iMechanicians or so.) After it too gets accepted and published, I will write yet another blog post, explaining how it does show some quantum mechanical-ness. … Who knows such a sequence could continue…

But such a series (of the simulations) wouldn’t be very long, either! The thing is this.

If your idea does indeed simplify certain matters, then you don’t have to argue a lot about it—people can see its truth real fast. Especially if it has to do with “hard” sciences like engineering—even physics!

If your basic idea itself isn’t so good, then, putting it in the engineering terms makes it more likely that even if you fail to get the weakness of your theory, someone else would. All in all, well and good for you.

As to the other possibility, namely, if your idea is good, but, despite putting it in the simpler terms (say in engineering or simulation terms), people still fail to see it, then, well, so long as your job (or money-making potential) itself is not endangered, then I think that it is a good policy to leave the mankind to its own follies. It is not your job to save the world, said Ayn Rand. Here, I believe her. (In fact, I believed in this insight even before I had ever run into Ayn Rand.)


As to the philosophic issues such as those involved in the foundations of QM—well, these are best tackled philosophically, not physics-wise. I wouldn’t use a physics-based argument to take a philosophic argument forward. Neither would I use a philosophical argument to take a physics-argument forward. The concerns and the methods of each are distinctly different, I have come to learn over a period of years.

Yes, you can use a physics situation as being illustrative of a philosophic point. But an illustration is not an argument; it is merely a device to make understanding easier. Similarly, you could try to invoke a philosophic point (say an epistemological point) to win a physics-based argument. But your effort would be futile. Philosophic ideas are so abstract that they can often be made to fit several different, competing, physics-related arguments. I would try to avoid both these errors.

But yes, as a matter of fact, certain issues that can only be described as philosophic ones, do happen to get involved when it comes to the area of the foundations of QM.

Now, here, given the nature of philosophy, and of its typical practitioners today (including those physicists who do dabble in philosophy), even if I become satisfied that I have resolved all the essential QM riddles, I still wouldn’t expect these philosophers to accept my ideas—not immediately anyway. In fact, as I anticipate things, philosophers, taken as a group, would never come to accept my position, I think. Such an happenstance is not necessarily to be ascribed to the personal failings of the individual philosophers (even if a lot of them actually do happen to be world-class stupid). That’s just how philosophy (as a discipline of studies) itself is like. A philosophy is a comprehensive view of existence—whether realistic or otherwise. That’s why it’s futile to expect that all of the philosophers would come to agree with you!

But yes, I would expect them to get the essence of my argument. And, many of them would, actually, get my argument, its logic—this part, I am quite sure of. But just the fact that they do understand my argument would not necessarily lead them to accept my positions, especially the idea that all the QM riddles are thereby resolved. That’s what I think.


Similarly, there also are a lot of mathematicians who dabble in the area of foundations of QM. What I said for philosophers also applies more or less equally well to them. They too would get my ideas immediately. But they too wouldn’t, therefore, come to accept my positions. Not immediately anyway. And in all probability, never ever in my lifetime or theirs.


So, there. Since I don’t expect an overwhelming acceptance of my ideas in the first place, there isn’t going to be any great disappointment either. The very expectations do differ.

Further, I must say this: I would never ever be able to rely on a purely abstract argument. That would feel like too dicey or flimsy to me. I would have to offer my arguments in terms of physically existing things, even if of a brand new kind. And, machines built out of them. At least, some working simulations. I would have to have these. I would not be able to rest on an abstract argument alone. To be satisfactory to me, I would have to actually build a machine—a soft machine—that works. And, doing just this part itself is going to be far more than enough to keep me happy. They don’t have to accept the conceptual arguments or the theory that goes with the design of such (soft) machines. It is enough that I play with my toys. And that’s another reason why I am not likely to derive a very deep sense of disenchantment or disappointment.


But if you ask me, the way I really, really like think about it is this:

If they decline my submission to the conference, I will write a paper about it, and send it, may be, to Sean Carroll or Sabine Hosenfelder or so. … The way I imagine things, he is then going to immediately translate my paper into German, add his own name to ensure its timely publication, and … . OK, you get the idea.

[In the interests of making this post completely idiot-proof, let me add: Here, in this sub-section, I was just kidding.]


2. The problem with the Many Worlds:

“Why the Many Worlds interpretation has many problems.”

Philip Ball argues in an article for the Quanta Mag [^] to the effect that many worlds means no world at all.

No, this is not exactly what he says. But what he says is clear enough that it is this conclusion which becomes inescapable.

As to what he actually says: Well, here is a passage, for instance:

“My own view is that the problems with the MWI are overwhelming—not because they show it must be wrong, but because they render it incoherent. It simply cannot be articulated meaningfully.”

In other words, Ball’s actual position is on the epistemic side, not on the ontic. However, his arguments are clear enough (and they often enough touch on issues that are fundamental enough) that the ontological implications of what he actually says, also become inescapable. OK, sometimes, the article unnecessarily takes detours into non-essentials, even into something like polemics. Still, overall, the write up is very good. Recommended very strongly.

Homework for you: If the Many Worlds idea is that bad, then explain why it might be that many otherwise reasonable people (for instance, Sean Carroll) do find the Many Worlds approach attractive. [No cheating. Think on your own and write. But if cheating is what you must do, then check out my past comment at some blog—I no longer remember where I wrote it, but probably it was on Roger Schlafly’s blog. My comment had tackled precisely this latter issue, in essential terms. Hints for your search: My comment had spoken about data structures like call-stacks and trees, and their unfolding.]


3. QM as an embarrassment to science:

“Why quantum mechanics is an “embarrassment” to science”

Brad Plumer in his brief note at the Washington Post [^] provides a link to a video by Sean Carroll.

Carroll is an effective communicator.

[Yes, he is the same one who I imagine is going to translate my article into German and… [Once again, to make this post idiot-proof: I was just kidding.]]


4. Growing younger…

I happened to take up a re-reading of David Ruelle’s book: “Chance and Chaos”. The last time I read it was in the early 1990s.

I felt younger! … May be if something strikes me while I am going through it after a gap of decades, I will come back and note it here.


5. Good introductory resources on nonlinear dynamics, catastrophe theory, and chaos theory:

If you are interested in the area of nonlinear dynamics, catastrophe theory and chaos theory, here are a few great resources:

  • For a long time, the best introduction to the topic was a brief write-up by Prof. Harrison of UToronto; it still remains one of the best [^].
  • Prof. Zeeman’s 1976 article for SciAm on the catastrophe theory is a classic. Prof. Zhigang Suo (of Harvard) has written a blog post of title “Recipe for catastrophe”at iMechanica [^], in which he helpfully provides a copy of Zeeman’s article. I have strongly recommended Zeeman’s write-up before, and I strongly recommend it once again. Go through it even if only to learn how to write for the layman and still not lose precision or quality.
  • As to a more recent introductory expositions, do see Prof. Geoff Boeing’s blog post: “Chaos theory and the logistic map” [^]. Boeing is a professor of urban planning, and not of engineering, physics, CS, or maths. But it is he who gives the clearest idea about the distinction between randomness and chaos that I have ever run into. (However, I only later gathered that he does have a UG in CS, and a PG in Information Management.) Easy to understand. Well ordered. Overall, very highly recommended.

Apart from it all:

Happy Diwali!


A song I like:

(Hindi) “tere humsafar geet hai tere…”
Music: R. D. Burman
Singers: Kishore Kumar, Mukesh, Asha Bhosale
Lyrics: Majrooh Sultanpuri

[Has this song been lifted from some Western song? At least inspired from one?

Here are the reasons for this suspicion: (1) It has a Western-sounding tune. It doesn’t sound Indian. There is no obvious basis either in the “raag-daari,” or in the Indian folk music. (ii) There are (beautiful) changes in the chords here. But there is no concept of chords in the traditional Indian music—basically, there is no concept of harmony in it, only of melody. (iii) Presence of “yoddling” (if that’s the right word for it). That too, by a female singer. That too, in the early 1970’s! Despite all  the “taan”s and “firat”s and all that, this sort of a thing (let’s call it yoddling) has never been a part of the traditional Indian music.

Chances are good that some of the notes were (perhaps very subconsciously) inspired from a Western tune. For instance, I can faintly hear “jingle bells” in the refrain. … But the question is: is there a more direct correspondence to a Western tune, or not.

And, if it was not lifted or inspired from a Western song, then it’s nothing but a work of an absolute genius. RD anyway was one—whether this particular song was inspired from some other song, or not.

But yes, I liked this song a great deal as a school-boy. It happened to strike me once again only recently (within the last couple of weeks or so). I found that I still love it just as much, if not more.]


[As usual, may be I will come back tomorrow or so, and edit/streamline this post a bit. One update done on 2018.11.04 08:26 IST. A second update done on 2018.11.04 21:01 IST. I will now leave this post in whatever shape it is in. Got to move on to trying out a few things in Python and all. Will keep you informed, probably after Diwali. In the meanwhile, take care and bye for now…]

The bouncing droplets imply having to drop the Bohmian approach?

If you are interested in the area of QM foundations, then may be you should drop everything at once, and go, check out the latest pop-sci news report: “Famous experiment dooms alternative to quantum weirdness” by Natalie Wolchover in the Quanta Magazine [^].

Remember the bouncing droplets experiments performed by Yves Couder and pals? In 2006, they had reported that they could get the famous interference pattern even if the bouncing droplets passed through the double slit arrangement only one at a time. … As the Quanta article now reports, it turns out that when other groups in the USA and France tried to reproduce this result (the single-particle double-slit interference), they could not.

“Repeat runs of the experiment, called the “double-slit experiment,” have contradicted Couder’s initial results and revealed the double-slit experiment to be the breaking point of both the bouncing-droplet analogy and de Broglie’s pilot-wave vision of quantum mechanics.”

Well, just an experimental failure or two in reproducing the interference, by itself, wouldn’t make for a “breaking point,”i.e., if the basic idea itself were to be sound. So the question now becomes whether the basic idea itself is sound enough or not.

Turns out that a new argument has been put forth, in the form of a thought experiment, which reportedly shows why and how the very basic idea itself must be regarded as faulty. This thought experiment has been proposed by a Danish professor of fluid dynamics, Prof. Tomas Bohr. (Yes, there is a relation: Prof. Tomas Bohr is a son of the Nobel laureate Aage Bohr, i.e., a grandson of the Nobel laureate Niels Bohr [^].)

Though related to QM foundations, this thought experiment is not very “philosophical” in nature; on the contrary, it is very, very “physics-like.” And the idea behind it also is “simple.” … It’s one of those ideas which make you exclaim “why didn’t I think of it before?”—at least the first time you run into it. Here is an excerpt (which actually is the caption for an immediately understandable diagram):

“Tomas Bohr’s variation on the famous double-slit experiment considers what would happen if a particle must go to one side or the other of a central dividing wall before passing through one of the slits. Quantum mechanics predicts that the wall will have no effect on the resulting double-slit interference pattern. Pilot-wave theory, however, predicts that the wall will prevent interference from happening.”

… Ummm… Not quite.

From whatever little I know about the pilot-wave theory, I think that the wall wouldn’t prevent the interference from occurring, even if you use this theory. … It all seems to depend on how you interpret (and/or extend) the pilot-wave theory. But if applied right (which means: in its own spirit), then I guess that the theory is just going to reproduce whatever it is that the mainstream QM predicts. Given this conclusion I have drawn about this approach, I did think that the above-quoted portion was a bit misleading.

The main text of the article then proceeds to more accurately point out the actual problem (i.e., the way Prof. Tomas Bohr apparently sees it):

“… the dividing-wall thought experiment highlights, in starkly simple form, the inherent problem with de Broglie’s idea. In a quantum reality driven by local interactions between a particle and a pilot wave, you lose the necessary symmetry to produce double-slit interference and other nonlocal quantum phenomena. An ethereal, nonlocal wave function is needed that can travel unimpeded on both sides of any wall. [snip] But with pilot waves, “since one of these sides in the experiment carries a particle and one doesn’t, you’ll never get that right. You’re breaking this very important symmetry in quantum mechanics.””

But isn’t the pilot wave precisely ethereal and nonlocal in nature, undergoing instantaneous changes to itself at all points of space? Doesn’t the pilot theory posit that this wave doesn’t consist of anything material that does the waving but is just a wave, all by itself?


…So, if you think it through, people seem to be mixing up two separate issues here:

  1. One issue is whether it will at all be possible for any real physical experiment done up with the bouncing droplets to be able to reproduce the predictions of QM or not.
  2. An entirely different issue is whether, in Bohr’s dividing-wall thought-experiment, the de Broglie-Bohm approach actually predicts something that is at a variance from what QM predicts or not.

These two indeed are separate issues, and I think that the critics are right on the first count, but not necessarily on the second.

Just to clarify: The interference pattern as predicted by the mainstream QM itself would undergo a change, a minor but a very definite change, once you introduce the middle dividing wall; it would be different from the pattern obtained for the “plain-vanilla” version of the interference chamber. And if what I understand about the Bohmian mechanics is correct, then it too would proceed to  produce exactly the same patterns in both these cases.


With that said, I would still like to remind you that my own understanding of the pilot-wave theory is only minimal, mostly at the level of browsing of the Wiki and a few home pages, and going through a few pop-sci level explanations by a few Bohmians. I have never actually sat down to actually go through even one paper on it fully (let alone systematically study an entire book or a whole series of articles on this topic).

For this reason, I would rather leave it to the “real” Bohmians to respond to this fresh argument by Prof. Tomas Bohr.

But yes, a new argument—or at least, an old argument but in a remarkably new settings—it sure seems to be.


How would the Bohmians respond?

If you ask me, from whatever I have gathered about the Bohmians and their approach, I think that they are simply going to be nonchalant about this new objection, too. I don’t think that you could possibly hope to pin them down with this argument either. They are simply going to bounce back, just like those drops. And the reason for that, in turn, is what I mentioned already here in this post: their pilot-wave is both ethereal and nonlocal in the first place.


So, yes, even if Wolchover’s report does seem to be misguided a bit, I still liked it, mainly because it was informative on both the sides: experimental as well as theoretical (viz., as related to the new thought-experiment).

In conclusion, even if the famous experiment does not doom this (Bohmian) alternative to the quantum weirdness, the basic reason for its unsinkability is this:

The Bohmian mechanics is just as weird as the mainstream QM is—even if the Bohmians habitually and routinely tell you otherwise.

When a Bohmian tells you that his theory is “sensible”/“realistic”/etc/, what he is talking about is: the nature of his original ambition—but not the actual nature of his actual theory.


To write anything further about QM is to begin dropping hints to my new approach. So let me stop right here.

[But yes, I am fully ready willing from my side to disclose all details about it at any time to a suitable audience. … Let physics professors in India respond to my requests to let me conduct an informal (but officially acknowledged) seminar on my new approach, and see if I get ready to deliver it right within a week’s time, or not!

[Keep waiting!]]


Regarding other things, as you know, the machine I am using right now is (very) slow. Even then, I have managed to run a couple of 10-line Python scripts, using VSCode.

I have immediately taken to liking this IDE “code-editor.” (Never had tried it before.) I like it a lot. … Just how much?

I think I can safely say that VSCode is the best thing to have happened to the programming world since VC++ 6 about two decades ago.

Yes, I have already stopped using PyCharm (which, IMHO, is now the second-best alternative, not the best).


No songs section this time, because I have already run a neat and beautiful song just yesterday. (Check out my previous post.) … OK, if some song strikes me in a day or two, I will return here to add it. Else, wait until the next time around. … Until then, take care and bye for now…


[Originally published on 16 October 2018 22:09 hrs IST. Minor editing (including to the title line) done by 17 October 2018 08:09 hrs IST.]

The quantum mechanical features of my laptop…

My laptop has developed certain quantum mechanical features after its recent repairs [^]. In particular, if I press the “power on” button, it does not always get “measured” into the “power-on” state.

That’s right. In starting the machine, it is not possible to predict when the power-on button may work, when it may lead to an actual boot-up. Sometimes it does, sometimes it doesn’t.

For instance, the last time I shut it down was on the last night, just before dinner. Then, after dinner, when I tried to restart it, the quantum mechanical features kicked in and the associated randomness was such that it simply refused the request. Ditto, this morning. Ditto, early afternoon today. But now (at around 18:00 hrs on 09 October), it somehow got up and going!


Fortunately, I have taken backup of crucial data (though not all). So, I can afford to look at it with a sense of humour.

But still, if I don’t come back for a somewhat longer period of time than is usual (about 8–10 days), then know that, in all probability, I was just waiting helplessly in getting this thing repaired, once again. (I plan to take it to the repairsman tomorrow morning.) …

…The real bad part isn’t this forced break in browsing or blogging. The real bad part is: my inability to continue with my ANN studies. It’s not possible to maintain any tempo in studies in this now-on-now-off sort of a manner—i.e., when the latter is not chosen by you.

Yes, I do like browsing, but once I get into the mood of studying a new topic (and, BTW, just reading through pop-sci articles does not count as studies) and especially if the studies also involve programming, then having these forced breaks is really bad. …

Anyway, bye for now, and take care.


PS: I added that note on browsing and then it struck me. Check out a few resources while I am gone and following up with the laptop repairs (and no links because right while writing this postscript, the machine crashed, and so I am somehow completing it using smartphone—I hate this stuff, I mean typing using at most two fingers, modtly just one):

  1. As to Frauchiger and Renner’s controversial much-discussed result, Chris Lee’s account at ArsTechnica is the simplest to follow. Go through it before any other sources/commentaries, whether to the version published recently in Nature Comm. or the earlier ones, since 2016.
  2. Carver Mead’s interview in the American Spectator makes for an interesting read even after almost two decades.
  3. Vinod Khosla’s prediction in 2017 that AI will make radiologists obsolete in 5 years’ time. One year is down already. And that way, the first time he made remarks to that sort of an effect were some 6+ years ago, in 2012!
  4. As to AI’s actual status today, see the Quanta Magazine article: “Machine learning confronts the elephant in the room” by Kevin Hartnett. Both funny and illuminating (esp. if you have some idea about how ML works).
  5. And, finally, a pretty interesting coverage of something about which I didn’t have any idea beforehand whatsoever: “New AI strategy mimics how brains learn to smell” by Jordana Cepelwicz in Quanta Mag.

Ok. Bye, really, for now. See you after the laptop begins working.


A Song I Like:
Indian, instrumental: Theme song of “Malgudi Days”
Music: L. Vaidyanathan

 

 

Suspension of blogging

Earlier, within a day of my posting the last blog entry here, i.e. right by 26th September morning, my laptop developed a problem, which led to a series of problems, which meant that, for a while, I could not at all blog or even surf on the ‘net effectively.

The smartphone screen is too small for me to do any serious browsing very effectively, let alone doing any blogging / writing / coding.


Never did buy into that idiotic Steve Jobs’ ridiculous claims anyway; bought my smartphone only because it’s good for things like storing phone numbers and listening to songs—and, yes, also for browsing a bit on google maps, and for taking snaps once in a while. But that’s about it. Nothing more than that. In particular, no social media, no banking, no e-payments, no emails, no real browsing. And, as to that prized (actually wretched) thin-ness and/or the delicate-ness of this goddamn thing. It is annoying. Just hold the damn thing in your palm, and it seems as if it itself auto-punches a few buttons and proceeds to close all the windows you had kept active. Or, worse: it launches a new window all by itself, forcing you to take a hike into an ad-link or sundry news item.

A good 1 inch thick and sturdy instrument with goodly big buttons would have been a better design choice, far better—not those bloody thin slivers on the sides which pass for buttons.


Anyway, the troubles with the laptop were these:

(i) In 2014, the screen panel of the laptop had cracked near a corner a bit, and then, subsequently, over a period of years or so, the front and the back covering parts of the screen panel had come to split apart, though only just slightly, only partially. I had shown the problem to the authorized dealer. He had advised me to do nothing about it. (If the problem were to be worse, he would have advised me to replace the screen, he had said. This was about 2 years ago.)

(ii) Then, slowly, friction began developing in only one of the hinges of the screen panel, the hinge near the same (cracked) corner. Finally, came this day when this partial splitting suddenly led to the panel-studs breaking apart (with a clean, brittle fracture). How did it happen? Because—I figured out only after the fact—the friction in the hinges together with the partial split up meant that an interior part of the screen panel was getting excessively bent, near the broken panel corner. This excessive bending was putting enormous bending moment on the studs holding the two parts of the partially split up panel near the hinges. (The overall frame of the screen panel was effectively acting as a large lever arm serving to bend the small plastic studs.)

(iii) In getting the above-mentioned problem fixed (by 29th September), some short-circuiting also occurred, with the result that now the graphics chip conked up. (No, the authorized dealer didn’t accept the machine. He advised replacement of both the mother-board and the screen. So, I did a google search and went through two private repairs-men, one of them being much better than the other. He fixed it right.)

Fixing the graphics problem took time because a replacement chip was not readily available in the local market, and there was a national holiday in between (on 2nd October) which kept the concerned courier services closed on that day.

(iv) Then, after replacing the graphics chip, once the screen finally started working, now it was the turn of the USB ports to begin malfunctioning. I got the delivery of my laptop last evening, and noticed it only after coming home.

This is a problem which has not yet been fixed. Getting it fixed is important because only 1 out of the 3 USB ports is currently functioning, and if it too is gone, backups will become impossible. I am not willing to lose my data once again.


The problem with the machine meant that my studies (and programming) of ANNs too got interrupted.

They still remain interrupted.

I guess the remaining problem (regarding the malfunctioning USB ports) is relatively a minor issue.

What I mean to say is that I could have resumed my regular sort of blogging.

However, last night, at around 00:40 hrs IST on 05 October 2018 there was a psychic attack on me which woke me up from sleep. (Also note the update in my last post). In view of this attack, I have finally decided to say it clear and loud, (perhaps once again):

“To hell with you, LA!”


If you wonder why I was so confident about “LA,” check out the visits pattern for the earlier part of the day yesterday, and juxtapose them with the usual patterns of visits here, overall.

In case you don’t know, all local newspapers of all California towns have been full of advertisements for psychic “consultants” providing their “services” for a fee—which would be almost nothing when measured in US dollars.


I have had enough of these bitches and bastards. That’s why, I am temporarily suspending my blog. When the psychic attacks come to a definitive stop, I will resume my own blogging, as also my commenting on other blogs, and posting any research notes etc.


And, yes, one more point: No, don’t believe what Ayn Rand Institute tells you. Psychic attacks are for real (though they are much, much rarer, and they indeed are effected in far more controlled ways, than what folklore or your average street-side vendor of the “services” says.)


No songs section this time round, for obvious reasons.


PS: BTW, no, I still haven’t seen my approach to QM mentioned in any of the papers / books, or in any discussions of any papers anywhere (including some widely followed blogs / twitter feeds), as yet. Apparently, my judgment that my approach is indeed new, continues to hold.

 

 

Absolutely Random Notings on QM—Part 3: Links to some (really) interesting material, with my comments

Links, and my comments:


The “pride of place” for this post goes to a link to this book:

Norsen, Travis (2017) “Foundations of Quantum Mechanics: An Exploration of the Physical Meaning of Quantum Theory,” Springer

This book is (i) the best supplementary book for a self-study of QM, and simultaneously, also (ii) the best text-book on a supplementary course on QM, both at the better-prepared UG / beginning PG level.

A bit expensive though, but extensive preview is available on Google books, here [^]. (I plan to buy it once I land a job.)

I was interested in the material from the first three chapters only, more or less. It was a delight even just browsing through these chapters. I intend to read it more carefully soon enough. But even on the first, rapid browsing, I noticed that several pieces of understanding that I had so painstakingly come to develop (over a period of years) are given quite straight-forwardly here, as if they were a matter of well known facts—even if other QM text-books only cursorily mention them, if at all.

For instance, see the explanation of entanglement here. Norsen begins by identifying that there is a single wavefunction, always—even for a multi-particle system. Then after some explanation, he states: “But, as usual in quantum mechanics, these states do not exhaust the possibilities—instead, they merely form a basis for the space of all possible wave functions. …”… Note the emphasis on the word “basis” which Norsen helpfully puts.

Putting this point (which Norsen discusses with a concrete example), but in my words: There is always a single wavefunction, and for a multi-particle system, its basis is bigger; it consists of the components of the tensor product (formed from the components of the basis of the constituent systems). Sometimes, the single wavefunction for the multi-particle system can be expressed as a result of a single tensor-product (in which case it’s a separable state), and at all other times, only as an algebraic sum of the results of many such tensor-products (in which case they all are entangled states).

Notice how there is no false start of going from two separate systems, and then attempting to forge a single system out of them. Notice how, therefore, there is no hand-waving at one electron being in one galaxy, and another electron in another galaxy, and so on, as if to apologize for the very idea of the separable states. Norsen achieves the correct effect by beginning on the right note: the emphasis on the single wavefunction for the system as a whole to begin with, and then clarifying, at the right place, that what the tensor product gives you is only the basis set for the composite wavefunction.

There are many neat passages like this in the text.


I was about to say that Norsen’s book is the Resnick and Halliday of QM, but then came to hesitate saying so, because I noticed something odd even if my browsing of the book was rapid and brief.

Then I ran into

Ian Durham’s review of Norsen’s book, at the FQXi blog,

which is our link # 2 for this post [^].

Durham helpfully brings out the following two points (which I then verified during a second visit to Norsen’s book): (i) Norsen’s book is not exactly at the UG level, and (ii) the book is a bit partial to Bell’s characterization of the quantum riddles as well as to the Bohmian approach for their resolution.

The second point—viz., Norsen’s fascination for / inclination towards Bell and Bohm (B&B for short)—becomes important only because the book is, otherwise, so good: it carries so many points that are not even passingly mentioned in other QM books, is well written (in a conversational style, as if a speech-to-text translator were skillfully employed), easy to understand, thorough, and overall (though I haven’t read even 25% of it, from whatever I have browsed), it otherwise seems fairly well balanced.

It is precisely because of these virtues that you might come out giving more weightage to the B&B company than is actually due to them.

Keep that warning somewhere at the back of your mind, but do go through the book anyway. It’s excellent.

At Amazon, it has got 5 reader reviews, all with 5 stars. If I were to bother doing a review there, I too perhaps would give it 5 stars—despite its shortcomings/weaknesses. OK. At least 4 stars. But mostly 5 though. … I am in an indeterminate state of their superposition.

… But mark my words. This book will have come to shape (or at least to influence) every good exposition of (i.e. introduction to) the area of the Foundations of QM, in the years to come. [I say that, because I honestly don’t expect a better book on this topic to arrive on the scene all that soon.]


Which brings us to someone who wouldn’t assign the |4\rangle + |5\rangle stars to this book. Namely, Lubos Motl.

If Norsen has moved in the Objectivist circles, and is partial to the B&B company, Motl has worked in the string theory, and is not just partial to it but even today defends it very vigorously—and oddly enough, also looks at that “supersymmetric world from a conservative viewpoint.” More relevant to us: Motl is not partial to the Copenhagen interpretation; he is all the way into it. … Anyway, being merely partial is something you wouldn’t expect from Motl, would you?

But, of course, Motl also has a very strong grasp of QM, and he displays it well (even powerfully) when he writes a post of the title:

“Postulates of quantum mechanics almost directly follow from experiments.” [^]

Err… Why “almost,” Lubos? 🙂

… Anyway, go through Motl’s post, even if you don’t like the author’s style or some of his expressions. It has a lot of educational material packed in it. Chances are, going through Motl’s posts (like the present one) will come to improve your understanding—even if you don’t share his position.

As to me: No, speaking from the new understanding which I have come to develop regarding the foundations of QM [^] and [^], I don’t think that all of Motl’s objections would carry. Even then, just for the sake of witnessing the tight weaving-in of the arguments, do go through Motl’s post.


Finally, a post at the SciAm blog:

“Coming to grips with the implications of quantum mechanics,” by Bernardo Kastrup, Henry P. Stapp, and Menas C. Kafatos, [^].

The authors say:

“… Taken together, these experiments [which validate the maths of QM] indicate that the everyday world we perceive does not exist until observed, which in turn suggests—as we shall argue in this essay—a primary role for mind in nature.”

No, it didn’t give me shivers or something. Hey, this is QM and its foundations, right? I am quite used to reading such declarations.

Except that, as I noted a few years ago on Scott Aaronson’s blog [I need to dig up and insert the link here], and then, recently, also at

Roger Schlafly’s blog [^],

you don’t need QM in order to commit the error of inserting consciousness into a physical theory. You can accomplish exactly the same thing also by using just the Newtonian particle mechanics in your philosophical arguments. Really.


Yes, I need to take that reply (at Schlafly’s blog), edit it a bit and post it as a separate entry at this blog. … Some other time.

For now, I have to run. I have to continue working on my approach so that I am able to answer the questions raised and discussed by people such as those mentioned in the links. But before that, let me jot down a general update.


A general update:

Oh, BTW, I have taken my previous QM-related post off the top spot.

That doesn’t mean anything. In particular, it doesn’t mean that after reading into materials such as that mentioned here, I have found some error in my approach or something like that. No. Not at all.

All it means is that I made it once again an ordinary post, not a sticky post. I am thinking of altering the layout of this blog, by creating a page that highlights that post, as well as some other posts.

But coming back to my approach: As a matter of fact, I have also written emails to a couple of physicists, one from IIT Bombay, and another from IISER Pune. However, things have not worked out yet—things like arranging for an informal seminar to be delivered by me to their students, or collaborating on some QM-related simulations together. (I could do the simulations on my own, but for the seminar, I would need an audience! One of them did reply, but we still have to shake our hands in the second round.)

In the meanwhile, I go jobless, but I keep myself busy. I am preparing a shortish set of write-ups / notes which could be used as a background material when (at some vague time in future) I go and talk to some students, say at IIT Bombay/IISER Pune. It won’t be comprehensive. It will be a little more than just a white-paper, but you couldn’t possibly call it even just the preliminary notes for my new approach. Such preliminary notes would come out only after I deliver a seminar or two, to physics professors + students.

At the time of delivering my proposed seminar, links like those I have given above, esp. Travis Norsen’s book, also should prove a lot useful.

But no, I haven’t seen something like my approach being covered anywhere, so far, not even Norsen’s book. There was a vague mention of just a preliminary part of it somewhere on Roger Schlafly’s blog several years ago, only once or so, but I can definitely say that I had already had grasped even that point on my own before Schlafly’s post came. And, as far as I know, Schlafly hasn’t come to pursue that thread at all, any time later…

But speaking overall, at least as of today, I think I am the only one who has pursued this (my) line of thought to the extent I have [^].

So, there. Bye for now.


I Song I Like:
(Hindi) “suno gajar kya gaaye…”
Singer: Geeta Dutt
Music: S. D. Burman
Lyrics: Sahir Ludhianvi
[There are two Geeta’s here, and both are very fascinating: Geeta Dutt in the audio, and Geeta Bali in the video. Go watch it; even the video is recommended.]


As usual, some editing after even posting, would be inevitable.

Some updates made and some streamlining done on 30 July 2018, 09:10 hrs IST.