The anti-, an anti-anti-, my negativism, and miscellaneous

Prologue:

A better title could very well have been “What I am up against.” However, that title, I thought, would be misleading. … I really am up against many things which I am going to touch on, in this post. But the point is, these are not the only things that I am up against, and so, that title would therefore be too general.


Part I: The Anti-

First, of course, comes the anti.

I stumbled across W. E. Lamb, Jr.’s excellent paper: “Anti-photon” (1995) Appl. Phys. B, vol. 60, p. 77–84. Here is the abstract:

“It should be apparent from the title of this article that the author does not like the use of the word “photon”, which dates from 1926. In his view, there is no such thing as a photon. Only a comedy of errors and historical accidents led to its popularity among physicists and optical scientists. I admit that the word is short and convenient. Its use is also habit forming. Similarly, one might find it convenient to speak of the “aether” or “vacuum” to stand for empty space, even if no such thing existed. There are very good substitute words for “photon”, (e.g., “radiation” or “light”), and for “photonics” (e.g., “optics” or “quantum optics”). Similar objections are possible to use of the word “phonon”, which dates from 1932. Objects like electrons, neutrinos of finite rest mass, or helium atoms can, under suitable conditions, be considered to be particles, since their theories then have viable non-relativistic and non-quantum limits. This paper outlines the main features of the quantum theory of radiation and indicates how they can be used to treat problems in quantum optics.”

BTW, in case you don’t know, W. E. Lamb, Jr., was an American, who received a Nobel in physics, for his work related to the fine structure of hydrogen [^].

So, that’s the first bit of what I am up against.

Also in case you didn’t notice, the initials are important; this isn’t (Sir) Horace Lamb (who, in case you don’t know, was that late 19th–early 20th century British guy who wrote books on hydrodynamics and acoustics that people like me still occasionally refer to [^]. (Lamb and Love continue to remain in circulation (even if a low circulation) among mechanicians even today. (Love, who? … That’s an exercise left for the reader…)))

Oh, BTW, talking of very good books that now have come in the public domain, and (the preparation required for) QM, and all the anti- and un- things, note that Professor Howard Georgi [^]’s excellent book on waves has by now come in the public domain [^].

(Even if only parenthetically, I have to note: I am anti-diversity, too. … This anti thing simply doesn’t leave me alone, though I will try to minimize its usage. Starting right now. … Georgi was born in California. He also maintains a page about women in physics [^].)

… Ummm, I’d better wrap up this part, and so…

… All in all, you can see that I don’t seem to be taking my opposition very seriously, though I admit I should start doing so some day. But the paper is great. (We were talking about the anti-photon paper, remember?) Here is an excerpt in case I haven’t already succeeded in persuading you to go through it, immediately:

“During my eight years in Berkeley, I had just one conversation with Lewis, in 1937, when he called me into his office to give some advice. It was: “When a theorist does not know what to do next, he is useless. An experimental scientist can always go into his laboratory and “polish up the brass”.”

This is the same Lewis who coined the word “photon.” … Now it convinces you to go through the paper, doesn’t it? (The paper is by Lamb; W. E. Lamb.)

[… On a more serious note, this paper has very good notings regarding the history of the idea of the photon.]


Part II: The Anti- Equals the Anti-Anti-

There is no typo here.

Even as I was recoiling off the glow (I won’t use “radiation” or “light”) of [the physics Nobel laureate] Lamb’s reputation, I began wondering precisely how I would counter his anti-photon argument. I even thought of doing a blog post about it. (After all, recently, Roger Schlafly has been hinting at that same idea, too. [May be TBD: insert links])

However, a better sense prevailed, and I did a Google search. I found a good blog post that gives a good rejoinder to the anti-photon arguments. The post is written in simple enough language that any one could understand. … But should I recommend it to you?… The thing is: It comes from a physicist who is reputed to have attempted teaching quantum physics to dogs. Or, at least, teaching people how to teach quantum physics, to dogs.

But of course, in physics, personalities don’t count, and neither do, you know, sort of like, “insults.” [I am also anti-animal rights, BTW [though all in favor of dogs].] And so, let me lead you to the relevant post.

The quantum physics-loving folks would have guessed the man by now (and every one, the fact that the author must be a man, not a woman). So the only remaining part would be which post by Chad Orzel. Here it is [^]. Once you finish reading it (including the comments on the post), then, also go through these couple of others posts by him touching on the same topic [^] [^] (and their blog comments). And, a great post (at wired.com!) by Rhett Allain [^] on the anti-photon side, to which Orzel makes a reference.

Orzel’s basic argument is that anti-bunching equals anti-anti-photon.

That explains the second part of the title.

But, before wrapping up this part, just a word on the PhD guides on the “polishing brass” side, and Indians. The anti-bunching experiments were done by Leonard Mandel [^], who among other things also guided Rupamanjari Ghosh’s PhD thesis. … Rupa…, who? I will save you the trouble of googling; see here: [^ (I am anti-government in education and science, too)] and here [^ (oh well, this post is getting just too long)].


Part III: My Negativism

Roger Schlafly has just recently written an interestingly long post on quantum entanglement. (Very long, by his standards.) In that post [^], he identifies himself as a logical positivist. This isn’t the first time that he has attributed logical positivism to his intellectual positions. Schlafly’s recent post is written, as usual, with good/great clarity

Now consider the premises, this time three, instead of the usual two: (i) Schlafly identifies himself as a logical positivist, (ii) I don’t agree with some part of his positions, and (iii) logic is logic—it cares for completeness.

Ergo, I must be a logical negativist.

That explains the third part of the title.

Some day I plan to write a post on the triplet and singlet states, and quantum entanglement.

Some still later day, I plan to explain how QM is incomplete, by pointing out how it can be made complete. … That is too big a goal to keep, you say?

Well, I do plan to at least explain in simpler terms the phenomenon of quantum entanglement, but only in reference to the text-book treatments. … That should be doable, what say?

… Don’t hold me responsible etc. on this promise; I am careless etc.; and so,  it might very well be in mid-2016 when I might actually deliver on it. … So, for the time being, make do with my logical negativism.


Part IV: Miscellaneous

M1: The preface to Georgi’s book notes the help he received while writing the book inter alia from (the same) Griffiths (as the one who has written very popular undergraduate text-books on electrodynamics and QM). (Griffiths studied at Harvard where Georgi has been a professor, though chances are they were contemporaries.) (No, this Griffiths isn’t the same as the Griffiths of fracture mechanics [^].) (Yes, this Georgi is the same as the one who has advocated the unparticle mechanics [^]. (But why didn’t he use the anti- prefix here?))

M2: The most succinct (and as far as I can make out, correct) treatment of the meaning of “hidden variables” has been not in the recent Internet writings on Bell’s inequalities but in Griffith’s undergraduate text-book on QM.

Why I mention this bit… That’s because, recently, the MIT professor Scott Aaronson had a field day about hidden variables (notably with Travis Norsen) [^], though since then he seems to have moved on to some other things related to theoretical computational complexity, e.g. this graph isomorphism-related thingie [^].

But, no, if you want to know about the so-called hidden variables well (and don’t have my “approach” or at least my “confidence”), then don’t look up the material on the ‘net or blog posts, esp. those by CS folks or complexity theorists. Instead, hit Griffith’s (text-)book.

M3: However, I am unhappy about Griffith’s treatment of the quantum postulates—he (like QChem and most all UG QM books) has only the usual \Psi and doesn’t include the spinor function right while discussing the state definition. Indeed, he continues implicitly treating the two in a somewhat disjoint manner even afterwards (exactly like all UG text-books do). Separable doesn’t mean disjointed.

I am also unhappy about Griffith’s (and every other QM text-book’s) treatment of the basic ideas of identical particles and their states—the treatments are just not conceptually clarifying enough. … May I assist you rewriting this topic, Professor Griffiths? … Oh well… Before I actually make that offer to him, I will try my hand at the task, at this blog…. Sometime in/after mid-2016. (Hopefully earlier.)

But, yes, if you ask me, it’s only the spin and identical particles that still remain truly nebulous topics for the student, today. With single-particle interference experiments and the ubiquity of simulations, one wouldn’t think that people would have too much difficulty with wave-particle duality or interference etc.

Contrast staring at one or two manually drawn static graphs in a book/paper, and imagining how things would change with time, under different governing equations and different boundary conditions, vs. going through simulations on your smartphone, adjusting FPS, changing boundary conditions with the flick of a button… Students (like me) must be having it exponentially easier to learn QM these days, as compared to those hapless 20th century guys.

The points where today’s students are likely to falter would be a bit more advanced ones, like angular momentum. In fact, today’s students don’t know angular momentum well even in the classical mechanics settings. (Ask yourself: how clear and confident are you about, say, Coriolis forces, say, as covered in Shames, or in Timoshenko and Young?).

So, to wrap up, it has to be identical particles and spin that still remain the really difficult topics. Now, it so happens that it is these concepts that underlie popular expositions of entanglement. Little surprise that people never get the confidence that they would be able to deal with entanglement right.

(Focusing on “just” two states of the spin up- and down-, and therefore treating the phenomenon via an abstract two component vector, and then thinking that starting a discussion with this “simple” vector, is a very bad idea, epistemologically speaking. … Yes, I am anti-Susskind’s “theoretical minimum,” too. And yes, Griffiths is right in choosing the traditional way (of the sequence in which to present the QM spin). It’s just that he needs to explain it in (even) better manner, that’s all….)

M4: The day before yesterday was the first time this year that I happened to finally sense that wonderful winter-time air of Pune’s, while returning in the evening from our college. (Monday was a working day for us; no continuous 9-day patch of a vacation.)

It still doesn’t feel like the Diwali air this year in Pune, but it’s getting close: I spotted some nice fog/mist on the nearby nallah (i.e. a small stream) and a nearby canal, a couple of times. …

This has been a year of (heavy) drought. And anyway, these days, there is virtually no difference between the Diwali days and the rest of the year. … Shopping malls are fully Diwali-like at any time of the year for those who have the money, and most women—whether working or otherwise—these days outsource their (Marathi) “chakalee”-making anyway—even during Diwali. So, there isn’t much of a difference between the Diwali days and the other days. Except for the weather. Weather still continues to change in a distinctly perceptible way sometime around Diwali. … So, that’s about all what Diwali means to me, this year.

And, of course, some memories of the magical Diwalis that I have spent in my childhood… Many of these were spent (at least for the (Marathi) “bhau-beej” day and a couple of days more) at my maternal uncle’s place (a very small town, a sub taluka-level place). … As far as I am concerned, those Diwali’s are still real; they would easily remain that way throughout my life.


PS: Having written the post, I just stepped into the kitchen to make me a cup of tea, and that’s when father told me that home-made (Marathi) “chakalee”s had arrived from our family friends just last evening; I didn’t know about it.

Instantaneously, my song-selection collapsed into an anti-previously measured state. (It happens. Real life is more weird than QM.)


Epilogue:

Happy Diwali!


PS (also) to Epilogue:

Excuse me for a couple of weeks now. I will continue studying QM (from text-books), but I will also have to be taking out my notes for an undergraduate course on CFD (computational fluid dynamics, in case you didn’t know) that I should be teaching the next semester—which begins right in mid-December. (In India, we don’t always follow the Christmas–New Year’s–Next Term sequence.) I anyway will also be traveling a bit (just short distances like Mumbai and Nasik or so) over the next couple of weeks. So, I don’t think I will have the time to write a post. (That, in fact, was the reason why I threw in a lot of stuff right in this post.)

… So, there… Take care, and best wishes, once again, for a bright and happy Diwali (and to those of you who start a new year in Diwali, best wishes for a happy and prosperous new year too.)


A Song I Like

(Marathi) “tabakaamadhye ithe tevatee…”  (search on the transcriptionally incorrect “divya divyanchi jyot”)
Singer: Asha Bhosale
Lyrics: Ravindra Bhat
Music: Sudhir Phadake

[PS: I kept on adding material after publication of post, and now it has become some 1.5 times the original one. Sorry about that (though I did all the revisions right within 18 hours of publication), but now I am going stop editing any further. Put up with my grammatical mistakes and awkward constructions, as usual. And, if in doubt, ask me! Bye for now.]

[E&OE]

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