A few UG questions on QM. A bit about what Ashok Chavan said. Tomorrow is the National Science Day—A bit about E. C. G. Sudarshan

A Few Questions That UG Students Should Ask Their QM Professors:

Here are a few questions that at least the better among our UG students should be asking of the professors teaching them QM. The questions appear in no particular order.

  • Why are quantum-mechanical forces conservative?
  • Does the usual time-dependent Schrodinger’s equation (TDSE) apply to propagation of photons? If yes, why does no textbook ever illustrate TDSE involving photons? If not, what principle goes against applicablity of TDSE to photons?
  • What kind of physics would result if the QM wavefunction were not to be complex-valued but real (scalar)-valued? What if the wavefunction were to be deterministic rather than probabilistic? What contradictions would result in each case?
  • Does QM at all need an interpretation? If yes, why? Why is it that no other theory of physics seems to need special efforts at interpreting it but only QM does, esp. so if all physics theories ultimately describe the same reality? If QM does not need an interpretation, why do people talk about the phrase: “interpretation of QM”? What do they mean by that phrase?
  • What, precisely, is the physical meaning of an operator? Please don’t simply repeat for us its definition. Instead, please give us the physical meaning of the concept. Or is it the case that no physical meaning is possible for this concept and that it is doomed to remain an exclusively mathematical concept? If yes, why use it in the postulates of a physical theory—without ever taking the care to define its physical correspondents?
  • Are all quantum-theoretical operators Hermitian? If yes, why? What physical fact does this property indicate/highlight/underscore? What if they are not Hermitian?
  • Give us one example of an important eigenvalue problem from classical mechanics in which the differential equation formalism is very clearly shown to be equivalent to the matrix formalism. (You don’ t have to work out the implications of this exercise for us; we will be able do it all by ourselves.)
  • Does the QM theory necessarily require the concept of a wavepacket when it comes to detailing what a QM particle is? If yes, why? What would happen if it were not a packet of waves but instead just a monochromatic wave? If the theory does not necessarily require packets of waves, then can you suggest us any alternative treatment—if there is one?
  • In every other differential equation that we have studied thus far, the primary unknown always carried some or the other physical units/dimensions. For example, for mechanical waves, the primary variable would be the displacement from the equilibrium position. But the QM wavefunction seems to be a dimensionless quantity; at least, textbooks don’t seem to note down any units for it. Is it a dimensionless quantity? Why? What important things does this tell us about the nature of theorization followed in QM?
  • Is QM an action-at-a-distance theory? Please think carefully before answering (LOL! We have read about the collapse theories too!)
  • How, precisely, does QM relate to the classical EM? Is the term V(x,y,z,t) in Schrodinger’s equation to be understood in the classical sense? If yes, why do people say that between the two, QM is more basic to EM?
  • Explain precisely how the Newtonian mechanics is implied by QM.

Enjoy!

Notes:
(i) While I seem to have answers to all these questions, so long as the physicists community (at least that in India—at least professors from reputed Indian institutes, teaching QM to UG students) doesn’t begin to recognize me and my work (e.g. such as that listed here),  I can’t make myself available to requests for answers—whether the requests to answer come from these professors or from their JEE-cleared or otherwise students.
(ii)  Of course, many of my answers are not as fully worked out as I would like to. But I at least have good lines of thought concerning even these. Further, my answers are likely to be, say, different in quality/depth from what the typical professors would be able to give. <evil grin/> (In other words, I recognize that my own answers might perhaps be wrong—how do you know you can rely on me? (LOL!))
(iii) Recognizing me, in this context, simply means: willingness to discuss QM with me (including, possibly, the willingness to teach me QM—I carry no illusion that I know all there is to know even for the basic or elementary QM.)
(iv) All these questions are to be treated at the UG level—it’s the UG students who should be raising these, and if I were to have QM at the UG level during my own coursework, I am sure I would have raised at least half of these right back then—chances are, all of them.

Ashok Is At It Again!

Our CM Ashok Chavan has developed his own particular mechanics for taking quantum leaps between (i) the utterly banal and (ii) the completely nonsensical. (He is not alone; all politicians, regardless of their political affiliations, display a similar behavior. But today, we are talking about the Young, Dynamic, Result-Oriented chief minister of Maharashtra.)

Yesterday or so, Ashok was observed to be occupying the second among the aforementioned pair of quantum states. He announced, in one line, if not in one breath, that (a) the State Government of Maharashtra would be spending public (i.e. individual taxpayer’s) money to build a museum to house Sachin Tendulkar’s personal belongings/things of cricket he has used over the years, and (b) Chavan/they would be recommending the Central Government of India that Sachin be awarded a Bharatratna (India’s highest civilian honor) apparently immediately.

This news came in even as the enormity of Sachin’s latest achievement (not to mention a re-appreciation of his cumulative achievements) was just sinking in. Interrupting it came in Ashok’s declaration. Upon hearing it, one found oneself caught in a dilemma: whether to laugh or to cry at these brazen suggestions. … Indeed, one even didn’t know where to begin! Hmmm… Let me give it a try…

Hello, Ashok! For precisely the same basic reasons that secularism is logical (and moral), so is a separation between the state and sports—exactly on the same lines as separation of state and science/education/economics [^]). Got it?

… I think he would get it—whether he agrees with me or not, and most probably, he won’t. But, yes, he has got an MBA. This doesn’t mean much by itself these days (as if it ever did!), but, he, I guess, did his MBA from Bombay (that’s what the city would be called back then), and this last—MBA from Bombay—would mean some thing. It would include at least, say, the “street smartness” to understand or “get” something like what I’ve just indicated above. Ok.

Next. I may be disappointing Tendulkar’s (enormous) fan following, but, what the heck, I have to say what is on my mind… And what I think about this issue is that Sachin Tendulkar does not deserve to be given a Bharatratna… Not yet, anyway.

Indeed, that Tendulkar should not be given a Bharatratna right away is so obvious to me that it does not even make for an interesting topic of discussion as far as I am concerned.

Far more interesting, to me, is a completely different question: why might people like Ashok Chavan have thought it OK (and not at all brazen) to go ahead and suggest that Tendulkar be given a Bharatratna…. Now, this question is far more interesting than collecting/repeating items of Sachin’s (actual) greatness, as far as I am concerned…

Of course, a clear answer can’t easily be had for a question like this. But one can at least exercise something of an educated guess… So, allow me to do just that…

The mind goes back a few years, may be a decade ago or so. The BJP+ had managed to grab power in India (a decidedly mixed nation). As is usual with any predominantly irrational regime, there is a need that the ruler in such a regime feels to make it appear as if he/they are more rational, etc. Propaganda machinery is created and/or deployed precisely for this reason; a truly free country would need no such machinery. Depending on the specific kind of the irrationality that the ruler carries with him, his propaganda machinery would either try to cover up/suppress the dramatic instances illustrating that particular form of irrationality, or, otherwise, project, out of proportion, precisely those people, organizations etc. which would make the rule/ruler seem more benign, more sound, more just.

In our times, and specific to BJP+, this meant, they would have to show as if they were, variously, (i) pro-Muslims (hence the need to show Naqvi in the foreground and the inclusion of the green color on their flags etc.), (ii) pro-reason (this, together with (i) explains the promotion of Dr. APJ Abdul Kalam), (iii) pro-life/living (hence the inclusion of the “feelgood” factor in the campaign), (iv) pro-achievement, and (v) not particularly favoring any religion—religion as such—etc. I haven’t given example for the last two. Let me begin with the last.

It was to portray themselves that they were not particularly favorable to any religion as such that the BJP+ movement laid over-emphasis on two aspects: (i) the spirituality movement, which often became the milder, more easily acceptable front for what actually were blatantly religious ideas, and (ii) the projection of cricket—a sport—as a religion.

Cricket has always been the greatest/most popular sport in India at least since the times of independence or so (even before that). It was the most loved game even during the golden days of Indian Hockey. However, in earlier times, it was never projected as a stand-in for religion. BJP+ did it. Even when, say, Sunil Gavaskar was producing some of the most spectacular moments in cricketing history, editors of that bygone era (of somewhat better media standards) were still being reluctant to portray him even as a God substitute—let alone as a God. In their own times, BJP+ intellectuals had every reason not to exercise such a refrain—they began projection of cricketers as Gods. Sachin happened to be around and happened to be the greatest among them all. Naturally, he was made the prime God.

Cricket as Religion. That was the general mantra of propaganda. The public needs enjoyment, it needs diversions, it needs to be kept confused. Cricket supplied the remedy.

It’s the editors and intellectuals of those times—about a decade or so ago—who are primarily responsible for the deification of cricket. For the reason stated above. Especially (but unfortunately not at all exclusively) the editors of The Times of India.

[Added on February 28. Sometimes, people ascribe the deification, or the media hyperbole, to the huge increases in money in the game. Sorry, this explanation cannot be correct. All that money can do is to magnify the material means available for projection of ideas; it cannot decide which ideas in particular are thus to be projected. Money by itself cannot formulate ideas or validate them or uphold them. And, even a rough glance at the history of ideas indicates that even if money might act as a magnifier of the material means, it has no essential impact on the turn of the historical events. There is a certain similarity to mathematics here: a thousand pages-long proof, built over years of strenuous hard work by a most gifted mathematician, printed on  the most expensive paper and published by a most influential house, still is no match for a single counter-example. … Ideas is the fundamental factor shaping the course of life and of events—whether of an individual or of a society.]

The Indira Congress, once it managed to come in power again, would of course find  it not at all inconvenient to continue with the same mantra: why disturb something ongoing if it doesn’t hurt the already existing vote-banks and also might garner popularity among urban youth—an important “ghaTak” in the changing/changed demographics? This explains why an Ashok Chavan wouldn’t at all find it circumspect, in any sense, to directly recommend Sachin for Bharatratna—the intellectual groundwork has already been laid, the acceptance for the hyperbole is already present. [… BTW, similar is the pattern of how, what people call “common sense,” comes to be in common circulation, in mixed—read semi-irrational—societies.]

Having said that, just one word about why I don’t think Sachin should be given Bharatratna, at least as of now…. Ummm… That way, I hardly care whether he gets the highest award or not. But even if a Bharatratna is to be given to a sportsman, I think it would make good sense if the award is  not made while he was still actively playing his game… (Similarly, it should not be given to a businessman while he was still actively managing his business, i.e., if he still was a CEO/MD, not just a Chairman of the Board/Consultant/Mentor etc. Similarly, for other professions…)

So, yes. Congratualations, Sachin, on your latest achievement (and all of them so far put together). But don’t take Ashok Chavan (or editors of newspapers, or mediamen or even your seniors like Kapil Dev and Sunil Gavaskar) very seriously… Just keep playing your game, to as much extent as you would like… (I do trust your decency; I have never doubted that you yourself would be able to come out and tell us when you think it’s time to say goodbye to the game.) In the end, when you retire, I might, perhaps, still have yet another argument as to why you should still not be given the Bharatratna. But this doesn’t at all mean that I am against your scaling ever greater heights in your chosen profession, or deriving enjoyment and making money for yourself out of these…. So, forget about Bharatratna and all, just go ahead and continue playing your game! … My honesty may be brutal, but at least my wishes are sincere—and this much, even you could easily tell, couldn’t you, “Sachyaa” (!!)

– – – – –

On Occasion of Tomorrow’s National Science Day: How About a “Bharatratna” for E. C. George Sudarshan?

Tomorrow, February 28th is the Nobel laureate Sir C. V. Raman’s birth-day the day on which Sir C. V. Raman made the discovery/wrote his paper/sent it for publication/it was published/something similar—the discovery for which he received his Nobel in physics. It is celebrated as the National Science Day in India.

While we are at it—the Bharatratna and Nobel laureates and all—I would like to make a suggestion.

Instead of giving Bharatratna to Sachin Tendulkar, I suggest, how about giving it this year to Professor E. C. George Sudarshan? [^][^]… I am just thinking aloud and suggesting a possibility, that’s all…

There was a bit of controversy concerning the Nobel prize for Physics in the year 2005. That year, Glauber received a part of the Physics Nobel for a certain piece of work—work for which, apparently, Sudarshan had been the actual pioneer.

It’s not possible for me to reach a good judgment about this matter, primarily because I have no expert knowledge of this field. Further, I enjoy no such luxury as to be able to summon experts and ask them to tell me the whats and the hows of this part of physics in essential terms understandable to me.  Yet, after reading about this controversy, I tend to think that (i) at least sometimes, Sudarshan’s supporters wrote their protests using words that were a bit too strong (“a sleight of hand…” etc.), and (ii) it was Sudarshan who was more deserving of the Nobel than Glauber anyway.

Why did I reach the second part of the conclusion—even if I have no direct knowledge of the field? Here are a few indirect pointers that I considered in reaching my conclusion:
(i) Sudarshan’s supporters directly tell you that facts are out there. I mean, they do it in a manner unlike the X-files and all. They give you specific dates. They give you specific references of specific journal papers by each of the authors in question.
(ii) They also talk in very specific terms about the particular content/ideas that were lacking (or had not yet been as consistently formed) in Glauber’s formulation vis-a-vis Sudarshan’s.
(iii) Sudarshan himself has written a public letter to the Nobel awards committee. Note, this is so unlike (a) an Indian professor (b) of the past generation (c) working in the USA (d) who has been a top-ranking physicist for decades. Further, none of his peers seem to have reacted against Sudarshan—despite the USA being such a freely talking society.

There also have been other issues concerning priority of Sudarshan’s work vis-a-vis Feynman’s and all. However, in my limited search, I could not find enough material to be able to come to even a guess, in this case. However, I do think that a note is in order. Just the way Sachin is not a God, so was not Feynman. Americans (and others) might have preferred to make Feynman into one. (Perhaps for a philosophically similar set of reasons as indicated above, who knows. I have not been residing and working in physics in USA through ’60s, ’70s and ’80s, and so, I can’t sense/tell immediately. But what I can tell, based on my cumulative seven years spent in the USA, is this much: if it can happen here, sometimes, it can very easily happen also in the USA. So, yes, such a thing could have easily happened in the ’60s and ’70s. Though, I don’t know whether it actually did or not, talking about this controversy concerning Feynman.)

All in all, even if not in fact a Nobel laureate, Sudarshan is right there—ahead of Glauber. That is my conclusion. I won’t mind being corrected if good evidence or very well-thought out arguments to the contrary are put forth—one tries to keep an active mind.

[Since I am talking pro-Sudarshan, here is the mandatory personal interests statement (so essential in today’s times and esp. so, on the Internet): I might apply to the Center for Philosophy and Foundations of Science [^] for some support or so in future; this Center was co-founded or so by Sudarshan. In the interest of completeness: this consideration did not at all enter my judgment. If you don’t believe me, get lost. Mandatory statement over.  ]

Ok. To come back to Bharatratna…

Consider the fact that at least Wikipedia lists Sudarshan [^] as an Indian citizen—not American. (BTW, if true, this could also very well be the reason why the Nobel went to Glauber and not to Sudarshan—and I am being primarily factual here, not sarcastic.)

Even if the above is not true and Sudarshan is an American citizen, consider the fact that Sudarshan has contributed enormously to science in India:

(i) He has worked as a resident Director of the Institute of Mathematical Sciences, Madras [^], for a considerable period of time (about a decade).
(ii) He has also been working with the IISc Bangalore (more than two decades).
(iii) He has helped found the Center for Philosophy and Foundations of Science, New Delhi [^], and helped get leading researchers (10+ Nobel laureates) in their various visiting programs over many years.
(iv) He has been in touch with Indian scientists working in India even otherwise.

All in all, considering all his achievements, and his continuing connection with India, E.C.G. Sudarshan would seem to make for an apt candidate for receiving the Bharatratna.

[Parenthetically, let me add: I “smell” that at least some of Sudarshan’s supporters seem to be communists. Frankly, I don’t know. I just “smell.” I could very very easily be wrong here. And, there are limits to how “nosy” one ought to get. After all, you could also argue the other way: viz., the very fact that Sudarshan’s name is George or that UT Austin considers it fit to employ him,  means that both he is a dogmatic Christian! … Keeping aside such flimsy charges, there is a more important issue: should such matters, if they are external to Sudarshan himself, reflect on him individually? esp. for making an award?]

Of course, again, all of this is, just a suggestion. If there are considerations/points going against awarding the Bharatratna to Sudarshan, one would be happy to know of the same. (After all, how deeply do we think about all such awards and all?)

. . .

But yes, coming back to the CM: Ashok, how about announcing forwarding Sudarshan’s name tomorrow—on the occasion of India’s (and not just Maharashtra’s) Science Day? (LOL!)

– – – – –

A Couple of Songs I Like [More or less at random]

1. (Hindi) “roj shaam aatee thee, magar aisi na thee…”
Singer: Lata Mangeshkar
Music: Laxmikant-Pyarelal
Lyrics: Majrooh Sultanpuri

2. (Hindi) “aaye tum yaad mujhe, gaane lagee har dhaDkan…”
Lyrics: Yogesh
Singer: Kishore Kumar
Music: S. D. Burman

[Updated on February 28.]

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