# I am keeping my New Year’s…

I am keeping my NYR [^], made last year.

No, really. I AM keeping my NYR. Here’s how.

December is meant for making resolutions. (It doesn’t matter whether it’s the 1st or the 31st; the month is [the?] December; that’s what matters.)

Done.

January is meant for making a time-table. … But it must be something on which you can execute. I have been actively engaged doing that. … You could see that, couldn’t you? … And, what’s more, you could’ve bet about it at any time in the past, too, couldn’t you?

Since execution can only follow, and not precede, planning, it must be February before execution proper itself can begin. As far as I am concerned, I will make sure of that. [And you know me. You know that I always deliver on all my promises, don’t you?]

March is known for madness. To be avoided, of course.

April is known for foolishness. To be avoided, as far as possible, but, hey, as “friends” of this blog, you know, it’s nothing to be afraid of!

May, in this part of the world, is far too hot for any one to handle it right, OK? The work-efficiency naturally drops down. This fact must be factored into any and every good piece of planning, I say! (Recall the British Governors and Other officers of the Bombay Presidency shifting their offices to Matheran/Mahabaleshwar during summer? [Anyone ever cared to measure the efficiency of this measure on their part? I mean, on work?])

Now, yes, June does bring in the [very welcome] monsoons, finally! But then, monsoon also is universally known to be the most romantic of all seasons. [It leaves a certain something of a feeling which ordinarily would require you to down a Sundowner or so. [I am trying to be honest, here!]… And then, even Kalidas would seem to agree. Remember (Sanskrit) “aashaaDhasya pratham…”? Naturally, the month is not very conducive to work, is it?]

OK.

This is [just] January, and my time-table is all done up and ready. Or, at least, it’s [at least] half-way through. …

I will really, really begin work in the second half of the year.

Bye until then.

A Song I Don’t Ever Recall Liking Back Then [When Things Mattered Far More Routinely in Far More Respects than They Do Today]

[Not too sure I like it today either. But there were certain happy isolated instances related to my more recent career which are associated with it. I had registered, but hadn’t known this fact, until recently.

But then, recently, I happened suddenly to “re-hear” the phrase (Hindi) “yeh kaunsaa…”, complete with the piece of the “sax” which follows it…

Then, the world had become [in a [comparatively] recent past] a slightly better place to live in.

So, I’d decided, not quite fully certain but still being inclined to this possibility, that I might actually like this song. … But I still don’t fully, you know… But I still do fully want to run it, you know…

Anyway, just listen to it…]

(Hindi) “chocolate, lime juice, ice-cream…” [No, it really is a Hindi song. Just listen to it further…]
Singer: Lata Mangeshkar [A peculiarity of this song is that precisely when [an aged] Lata sounds [a bit] heavy [of course due to the age not to mention the pressures of the day-to-day work and every one’s normal inability to hit the sweet spot every time!], the directors of the movie and the music together focus your attention on a rather cheerfully smiling and dancing Madhuri. [No, never been one of my favorite actresses, but then, that’s an entirely different story altogether.]]
Music: Ramlaxman
Lyrics: Dev Kohli [?]

[PS: And, coming to the video of this song, did you notice that the hero drives a Maruti Gypsy?

I mean, ask any NRI in USA, and they he will tell you that it was because this was an early 90’s movie; the fruits of the [half-/quarter-/oct-something-/etc.] economic liberalization had still not been had by the general public; the liberalization they [I mean these NRIs] had brought about.

If these [I mean the economic freedoms] were to be brought about , they could easily point out, with good amount of references to Hindi movies of the recent years, that the presence on Indian roads of the [government-subsidized-diesel-driven] SUVs could easily have been seen in the same movie!!!

Hmmm…  Point[s] taken.]

[A bit of an editing is still due, I am sure… TBD, when I get the time to do so…]

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# Yes I know it!

Note: A long update was posted on 12th December 2017, 11:35 IST.

This post is spurred by my browsing of certain twitter feeds of certain pop-sci. writers.

The URL being highlighted—and it would be, say, “negligible,” but for the reputation of the Web domain name on which it appears—is this: [^].

I want to remind you that I know the answers to all the essential quantum mysteries.

Not only that, I also want to remind you that I can discuss about them, in person.

It’s just that my circumstances—past, and present (though I don’t know about future)—which compel me to say, definitely, that I am not available for writing it down for you (i.e. for the layman) whether here or elsewhere, as of now. Neither am I available for discussions on Skype, or via video conferencing, or with whatever “remoting” mode you have in mind. Uh… Yes… WhatsApp? Include it, too. Or something—anything—like that. Whether such requests come from some millionaire Indian in USA (and there are tons of them out there), or otherwise. Nope. A flat no is the answer for all such requests. They are out of question, bounds… At least for now.

… Things may change in future, but at least for the time being, the discussions would have to be with those who already have studied (the non-relativistic) quantum physics as it is taught in universities, up to graduate (PhD) level.

And, you have to have discussions in person. That’s the firm condition being set (for the gain of their knowledge 🙂 ).

Just wanted to remind you, that’s all!

Update on 12th December 2017, 11:35 AM IST:

I have moved the update to a new post.

A Song I Like:

(Western, Instrumental) “Berlin Melody”
Credits: Billy Vaughn

[The same 45 RPM thingie [as in here [^], and here [^]] . … I was always unsure whether I liked this one better or the “Come September” one. … Guess, after the n-th thought, that it was this one. There is an odd-even thing about it. For odd ‘n” I think this one is better. For even ‘n’, I think the “Come September” is better.

… And then, there also are a few more musical goodies which came my way during that vacation, and I will make sure that they find their way to you too….

Actually, it’s not the simple odd-even thing. The maths here is more complicated than just the binary logic. It’s an n-ary logic. And, I am “equally” divided among them all. (4+ decades later, I still remain divided.)… (But perhaps the “best” of them was a Marathi one, though it clearly showed a best sort of a learning coming from also the Western music. I will share it the next time.)]

[As usual, may be, another revision [?]… Is it due? Yes, one was due. Have edited streamlined the main post, and then, also added a long update on 12th December 2017, as noted above.]

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# Fluxes, scalars, vectors, tensors…. and, running in circles about them!

0. This post is written for those who know something about Thermal Engineering (i.e., fluid dynamics, heat transfer, and transport phenomena) say up to the UG level at least. [A knowledge of Design Engineering, in particular, the tensors as they appear in solid mechanics, would be helpful to have but not necessary. After all, contrary to what many UGC and AICTE-approved (Full) Professors of Mechanical Engineering teaching ME (Mech – Design Engineering) courses in SPPU and other Indian universities believe, tensors not only appear also in fluid mechanics, but, in fact, the fluids phenomena make it (only so slightly) easier to understand this concept. [But all these cartoons characters, even if they don’t know even this plain and simple a fact, can always be fully relied (by anyone) about raising objections about my Metallurgy background, when it comes to my own approval, at any time! [Indians!!]]]

In this post, I write a bit about the following question:

Why is the flux $\vec{J}$ of a scalar $\phi$ a vector quantity, and not a mere number (which is aka a “scalar,” in certain contexts)? Why is it not a tensor—whatever the hell the term means, physically?

And, what is the best way to define a flux vector anyway?

1.

One easy answer is that if the flux is a vector, then we can establish a flux-gradient relationship. Such relationships happen to appear as statements of physical laws in all the disciplines wherever the idea of a continuum was found useful. So the scope of the applicability of the flux-gradient relationships is very vast.

The reason to define the flux as a vector, then, becomes: because the gradient of a scalar field is a vector field, that’s why.

But this answer only tells us about one of the end-purposes of the concept, viz., how it can be used. And then the answer provided is: for the formulation of a physical law. But this answer tells us nothing by way of the very meaning of the concept of flux itself.

2.

Another easy answer is that if it is a vector quantity, then it simplifies the maths involved. Instead of remembering having to take the right $\theta$ and then multiplying the relevant scalar quantity by the $\cos$ of this $\theta$, we can more succinctly write:

$q = \vec{J} \cdot \vec{S}$ (Eq. 1)

where $q$ is the quantity of $\phi$, an intensive scalar property of the fluid flowing across a given finite surface, $\vec{S}$, and $\vec{J}$ is the flux of $\Phi$, the extensive quantity corresponding to the intensive quantity $\phi$.

However, apart from being a mere convenience of notation—a useful shorthand—this answer once again touches only on the end-purpose, viz., the fact that the idea of flux can be used to calculate the amount $q$ of the transported property $\Phi$.

There also is another problem with this, second, answer.

Notice that in Eq. 1, $\vec{J}$ has not been defined independently of the “dotting” operation.

If you have an equation in which the very quantity to be defined itself has an operator acting on it on one side of an equation, and then, if a suitable anti- or inverse-operator is available, then you can apply the inverse operator on both sides of the equation, and thereby “free-up” the quantity to be defined itself. This way, the quantity to be defined becomes available all by itself, and so, its definition in terms of certain hierarchically preceding other quantities also becomes straight-forward.

OK, the description looks more complex than it is, so let me illustrate it with a concrete example.

Suppose you want to define some vector $\vec{T}$, but the only basic equation available to you is:

$\vec{R} = \int \text{d} x \vec{T}$, (Eq. 2)

assuming that $\vec{T}$ is a function of position $x$.

In Eq. 2, first, the integral operator must operate on $\vec{T}(x)$ so as to produce some other quantity, here, $\vec{R}$. Thus, Eq. 2 can be taken as a definition for $\vec{R}$, but not for $\vec{T}$.

However, fortunately, a suitable inverse operator is available here; the inverse of integration is differentiation. So, what we do is to apply this inverse operator on both sides. On the right hand-side, it acts to let $\vec{T}$ be free of any operator, to give you:

$\dfrac{\text{d}\vec{R}}{\text{d}x} = \vec{T}$ (Eq. 3)

It is the Eq. 3 which can now be used as a definition of $\vec{T}$.

In principle, you don’t have to go to Eq. 3. In principle, you could perhaps venture to use a bit of notation abuse (the way the good folks in the calculus of variations and integral transforms always did), and say that the Eq. 2 itself is fully acceptable as a definition of $\vec{T}$. IMO, despite the appeal to “principles”, it still is an abuse of notation. However, I can see that the argument does have at least some point about it.

But the real trouble with using Eq. 1 (reproduced below)

$q = \vec{J} \cdot \vec{S}$ (Eq. 1)

as a definition for $\vec{J}$ is that no suitable inverse operator exists when it comes to the dot operator.

3.

Let’s try another way to attempt defining the flux vector, and see what it leads to. This approach goes via the following equation:

$\vec{J} \equiv \dfrac{q}{|\vec{S}|} \hat{n}$ (Eq. 4)

where $\hat{n}$ is the unit normal to the surface $\vec{S}$, defined thus:

$\hat{n} \equiv \dfrac{\vec{S}}{|\vec{S}|}$ (Eq. 5)

Then, as the crucial next step, we introduce one more equation for $q$, one that is independent of $\vec{J}$. For phenomena involving fluid flows, this extra equation is quite simple to find:

$q = \phi \rho \dfrac{\Omega_{\text{traced}}}{\Delta t}$ (Eq. 6)

where $\phi$ is the mass-density of $\Phi$ (the scalar field whose flux we want to define), $\rho$ is the volume-density of mass itself, and $\Omega_{\text{traced}}$ is the volume that is imaginarily traced by that specific portion of fluid which has imaginarily flowed across the surface $\vec{S}$ in an arbitrary but small interval of time $\Delta t$. Notice that $\Phi$ is the extensive scalar property being transported via the fluid flow across the given surface, whereas $\phi$ is the corresponding intensive quantity.

Now express $\Omega_{\text{traced}}$ in terms of the imagined maximum normal distance from the plane $\vec{S}$ up to which the forward moving front is found extended after $\Delta t$. Thus,

$\Omega_{\text{traced}} = \xi |\vec{S}|$ (Eq. 7)

where $\xi$ is the traced distance (measured in a direction normal to $\vec{S}$). Now, using the geometric property for the area of parallelograms, we have that:

$\xi = \delta \cos\theta$ (Eq. 8)

where $\delta$ is the traced distance in the direction of the flow, and $\theta$ is the angle between the unit normal to the plane $\hat{n}$ and the flow velocity vector $\vec{U}$. Using vector notation, Eq. 8 can be expressed as:

$\xi = \vec{\delta} \cdot \hat{n}$ (Eq. 9)

Now, by definition of $\vec{U}$:

$\vec{\delta} = \vec{U} \Delta t$, (Eq. 10)

Substituting Eq. 10 into Eq. 9, we get:

$\xi = \vec{U} \Delta t \cdot \hat{n}$ (Eq. 11)

Substituting Eq. 11 into Eq. 7, we get:

$\Omega_{\text{traced}} = \vec{U} \Delta t \cdot \hat{n} |\vec{S}|$ (Eq. 12)

Substituting Eq. 12 into Eq. 6, we get:

$q = \phi \rho \dfrac{\vec{U} \Delta t \cdot \hat{n} |\vec{S}|}{\Delta t}$ (Eq. 13)

Cancelling out the $\Delta t$, Eq. 13 becomes:

$q = \phi \rho \vec{U} \cdot \hat{n} |\vec{S}|$ (Eq. 14)

Having got an expression for $q$ that is independent of $\vec{J}$, we can now use it in order to define $\vec{J}$. Thus, substituting Eq. 14 into Eq. 4:

$\vec{J} \equiv \dfrac{q}{|\vec{S}|} \hat{n} = \dfrac{\phi \rho \vec{U} \cdot \hat{n} |\vec{S}|}{|\vec{S}|} \hat{n}$ (Eq. 16)

Cancelling out the two $|\vec{S}|$s (because it’s a scalar—you can always divide any term by a scalar (or even  by a complex number) but not by a vector), we finally get:

$\vec{J} \equiv \phi \rho \vec{U} \cdot \hat{n} \hat{n}$ (Eq. 17)

In Eq. 17, there is this curious sequence: $\hat{n} \hat{n}$.

It’s a sequence of two vectors, but the vectors apparently are not connected by any of the operators that are taught in the Engineering Maths courses on vector algebra and calculus—there is neither the dot ($\cdot$) operator nor the cross $\times$ operator appearing in between the two $\hat{n}$s.

But, for the time being, let’s not get too much perturbed by the weird-looking sequence. For the time being, you can mentally insert parentheses like these:

$\vec{J} \equiv \left[ \left( \phi \rho \vec{U} \right) \cdot \left( \hat{n} \right) \right] \hat{n}$ (Eq. 18)

and see that each of the two terms within the parentheses is a vector, and that these two vectors are connected by a dot operator so that the terms within the square brackets all evaluate to a scalar. According to Eq. 18, the scalar magnitude of the flux vector is:

$|\vec{J}| = \left( \phi \rho \vec{U}\right) \cdot \left( \hat{n} \right)$ (Eq. 19)

and its direction is given by: $\hat{n}$ (the second one, i.e., the one which appears in Eq. 18 but not in Eq. 19).

5.

We explained away our difficulty about Eq. 17 by inserting parentheses at suitable places. But this procedure of inserting mere parentheses looks, by itself, conceptually very attractive, doesn’t it?

If by not changing any of the quantities or the order in which they appear, and if by just inserting parentheses, an equation somehow begins to make perfect sense (i.e., if it seems to acquire a good physical meaning), then we have to wonder:

Since it is possible to insert parentheses in Eq. 17 in some other way, in some other places—to group the quantities in some other way—what physical meaning would such an alternative grouping have?

That’s a delectable possibility, potentially opening new vistas of physico-mathematical reasonings for us. So, let’s pursue it a bit.

What if the parentheses were to be inserted the following way?:

$\vec{J} \equiv \left( \hat{n} \hat{n} \right) \cdot \left( \phi \rho \vec{U} \right)$ (Eq. 20)

On the right hand-side, the terms in the second set of parentheses evaluate to a vector, as usual. However, the terms in the first set of parentheses are special.

The fact of the matter is, there is an implicit operator connecting the two vectors, and if it is made explicit, Eq. 20 would rather be written as:

$\vec{J} \equiv \left( \hat{n} \otimes \hat{n} \right) \cdot \left( \phi \rho \vec{U} \right)$ (Eq. 21)

The $\otimes$ operator, as it so happens, is a binary operator that operates on two vectors (which in general need not necessarily be one and the same vector as is the case here, and whose order with respect to the operator does matter). It produces a new mathematical object called the tensor.

The general form of Eq. 21 is like the following:

$\vec{V} = \vec{\vec{T}} \cdot \vec{U}$ (Eq. 22)

where we have put two arrows on the top of the tensor, to bring out the idea that it has something to do with two vectors (in a certain order). Eq. 22 may be read as the following: Begin with an input vector $\vec{U}$. When it is multiplied by the tensor $\vec{\vec{T}}$, we get another vector, the output vector: $\vec{V}$. The tensor quantity $\vec{\vec{T}}$ is thus a mapping between an arbitrary input vector and its uniquely corresponding output vector. It also may be thought of as a unary operator which accepts a vector on its right hand-side as an input, and transforms it into the corresponding output vector.

6. “Where am I?…”

Now is the time to take a pause and ponder about a few things. Let me begin doing that, by raising a few questions for you:

Q. 6.1:

What kind of a bargain have we ended up with? We wanted to show how the flux of a scalar field $\Phi$ must be a vector. However, in the process, we seem to have adopted an approach which says that the only way the flux—a vector—can at all be defined is in reference to a tensor—a more advanced concept.

Instead of simplifying things, we seem to have ended up complicating the matters. … Have we? really? …Can we keep the physical essentials of the approach all the same and yet, in our definition of the flux vector, don’t have to make a reference to the tensor concept? exactly how?

(Hint: Look at the above development very carefully once again!)

Q. 6.2:

In Eq. 20, we put the parentheses in this way:

$\vec{J} \equiv \left( \hat{n} \hat{n} \right) \cdot \left( \phi \rho \vec{U} \right)$ (Eq. 20, reproduced)

What would happen if we were to group the same quantities, but alter the order of the operands for the dot operator?  After all, the dot product is commutative, right? So, we could have easily written Eq. 20 rather as:

$\vec{J} \equiv \left( \phi \rho \vec{U} \right) \cdot \left( \hat{n} \hat{n} \right)$ (Eq. 21)

What could be the reason why in writing Eq. 20, we might have made the choice we did?

Q. 6.3:

We wanted to define the flux vector for all fluid-mechanical flow phenomena. But in Eq. 21, reproduced below, what we ended up having was the following:

$\vec{J} \equiv \left( \phi \rho \vec{U} \right) \cdot \left( \hat{n} \otimes \hat{n} \right)$ (Eq. 21, reproduced)

Now, from our knowledge of fluid dynamics, we know that Eq. 21 seemingly stands only for one kind of a flux, namely, the convective flux. But what about the diffusive flux? (To know the difference between the two, consult any good book/course-notes on CFD using FVM, e.g. Jayathi Murthy’s notes at Purdue, or Versteeg and Malasekara’s text.)

Q. 6.4:

Try to pursue this line of thought a bit:

$q = \vec{J} \cdot \vec{S}$ (Eq. 1, reproduced)

Express $\vec{S}$ as a product of its magnitude and direction:

$q = \vec{J} \cdot |\vec{S}| \hat{n}$ (Eq. 23)

Divide both sides of Eq. 23 by $|\vec{S}|$:

$\dfrac{q}{|\vec{S}|} = \vec{J} \cdot \hat{n}$ (Eq. 24)

“Multiply” both sides of Eq. 24 by $\hat{n}$:

$\dfrac{q} {|\vec{S}|} \hat{n} = \vec{J} \cdot \hat{n} \hat{n}$ (Eq. 25)

We seem to have ended up with a tensor once again! (and more rapidly than in the development in section 4. above).

Now, looking at what kind of a change the left hand-side of Eq. 24 undergoes when we “multiply” it by a vector (which is: $\hat{n}$), can you guess something about what the “multiplication” on the right hand-side by $\hat{n}$ might mean? Here is a hint:

To multiply a scalar by a vector is meaningless, really speaking. First, you need to have a vector space, and then, you are allowed to take any arbitrary vector from that space, and scale it up (without changing its direction) by multiplying it with a number that acts as a scalar. The result at least looks the same as “multiplying” a scalar by a vector.

What then might be happening on the right hand side?

Q.6.5:

Recall your knowledge (i) that vectors can be expressed as single-column or single-row matrices, and (ii) how matrices can be algebraically manipulated, esp. the rules for their multiplications.

Try to put the above developments using an explicit matrix notation.

In particular, pay particular attention to the matrix-algebraic notation for the dot product between a row- or column-vector and a square matrix, and the effect it has on your answer to question Q.6.2. above. [Hint: Try to use the transpose operator if you reach what looks like a dead-end.]

Q.6.6.

Suppose I introduce the following definitions: All single-column matrices are “primary” vectors (whatever the hell it may mean), and all single-row matrices are “dual” vectors (once again, whatever the hell it may mean).

Given these definitions, you can see that any primary vector can be turned into its corresponding dual vector simply by applying the transpose operator to it. Taking the logic to full generality, the entirety of a given primary vector-space can then be transformed into a certain corresponding vector space, called the dual space.

Now, using these definitions, and in reference to the definition of the flux vector via a tensor (Eq. 21), but with the equation now re-cast into the language of matrices, try to identify the physical meaning the concept of “dual” space. [If you fail to, I will sure provide a hint.]

As a part of this exercise, you will also be able to figure out which of the two $\hat{n}$s forms the “primary” vector space and which $\hat{n}$ forms the dual space, if the tensor product $\hat{n}\otimes\hat{n}$ itself appears (i) before the dot operator or (ii) after the dot operator, in the definition of the flux vector. Knowing the physical meaning for the concept of the dual space of a given vector space, you can then see what the physical meaning of the tensor product of the unit normal vectors ($\hat{n}$s) is, here.

Over to you. [And also to the UGC/AICTE-Approved Full Professors of Mechanical Engineering in SPPU and in other similar Indian universities. [Indians!!]]

A Song I Like:

[TBD, after I make sure all LaTeX entries have come out right, which may very well be tomorrow or the day after…]

In the recent couple of weeks, I had not found much time to check out blogs on a very regular basis. But today I did find some free time, and so I did do a routine round-up of the blogs. In the process, I came across a couple of interesting posts by Prof. Dheeraj Sanghi of IIIT Delhi. (Yes, it’s IIIT Delhi, not IIT Delhi.)

The latest post by Prof. Sanghi is about achieving excellence in Indian universities [^]. He offers valuable insights by taking a specific example, viz., that of the IIIT Delhi. I would like to leave this post for the attention of [who else] the education barons in Pune and the SPPU authorities. [Addendum: Also this post [^] by Prof. Pankaj Jalote, Director of IIIT Delhi.]

Prof. Sanghi’s second (i.e. earlier) post is about the current (dismal) state of the CS education in this country. [^].

As someone who has a direct work-experience in both the IT industry as well as in teaching in mechanical engineering departments in “private” engineering colleges in India, the general impression I seem to have developed seemed to be a bit at odds with what was being reported in this post by Prof. Sanghi (and by his readers, in its comments section). Of course, Prof. Sanghi was restricting himself only to the CS graduates, but still, the comments did hint at the overall trend, too.

So, I began writing a comment at Prof. Sanghi’s blog, but, as usual, my comment soon grew too big. It became big enough that I finally had to convert it into a separate post here. Let me share these thoughts of mine, below.

As compared to the CS graduates in India, and speaking in strictly relative terms, the mechanical engineering students seem to be doing better, much better, as far the actual learning being done over the 4 UG years is concerned. Not just the top 1–2%, but even the top 15–20% of the mechanical engineering students, perhaps even the top quarter, do seem to be doing fairly OK—even if it could be, perhaps, only at a minimally adequate level when compared to the international standards.

… No, even for the top quarter of the total student population (in mechanical engineering, in “private” colleges), their fundamental concepts aren’t always as clear as they need to be. More important, excepting the top (may be) 2–5%, others within the top quarter don’t seem to be learning the art of conceptual analysis of mathematics, as such. They probably would not always be able to figure out the meaning of even a simplest variation on an equation they have already studied.

For instance, even after completing a course (or one-half part of a semester-long course) on vibrations, if they are shown the following equation for the classical transverse waves on a string:

$\dfrac{\partial^2 \psi(x,t)}{\partial x^2} + U(x,t) = \dfrac{1}{c^2}\dfrac{\partial^2 \psi(x,t)}{\partial t^2}$,

most of them wouldn’t be able to tell the physical meaning of the second term on the left hand-side—not even if they are asked to work on it purely at their own convenience, at home, and not on-the-fly and under pressure, say during a job interview or a viva voce examination.

However, change the notation used for second term from $U(x,t)$ to $S(x,t)$ or $F(x,t)$, and then, suddenly, the bulb might flash on, but for only some of the top quarter—not all. … This would be the case, even if in their course on heat transfer, they have been taught the detailed derivation of a somewhat analogous equation: the equation of heat conduction with the most general case, including the possibly non-uniform and unsteady internal heat generation. … I am talking about the top 25% of the graduating mechanical engineers from private engineering colleges in SPPU and University of Mumbai. Which means, after leaving aside a lot of other top people who go to IITs and other reputed colleges like BITS Pilani, COEP, VJTI, etc.

IMO, their professors are more responsible for the lack of developing such skills than are the students themselves. (I was talking of the top quarter of the students.)

Yet, I also think that these students (the top quarter) are at least “passable” as engineers, in some sense of the term, if not better. I mean to say, looking at their seminars (i.e. the independent but guided special studies, mostly on the student-selected topics, for which they have to produce a small report and make a 10–15 minutes’ presentation) and also looking at how they work during their final year projects, sure, they do seem to have picked up some definite competencies in mechanical engineering proper. In their projects, most of the times, these students may only be reproducing some already reported results, or trying out minor variations on existing machine designs, which is what is expected at the UG level in our university system anyway. But still, my point is, they often are seen taking some good efforts in actually fabricating machines on their own, and sometimes they even come up with some good, creative, or cost-effective ideas in their design- or fabrication-activities.

Once again, let me remind you: I was talking about only the top quarter or so of the total students in private colleges (and from mechanical engineering).

The bottom half is overall quite discouraging. The bottom quarter of the degree holders are mostly not even worth giving a post X-standard, 3 year’s diploma certificate. They wouldn’t be able to write even a 5 page report on their own. They wouldn’t be able to even use the routine metrological instruments/gauges right. … Let’s leave them aside for now.

But the top quarter in the mechanical departments certainly seems to be doing relatively better, as compared to the those from the CS departments. … I mean to say: if these CS folks are unable to write on their own even just a linked-list program in C (using pointers and memory allocation on the heap), or if their final-year projects wouldn’t exceed (independently written) 100+ lines of code… Well, what then is left on this side for making comparisons anyway? … Contrast: At COEP, my 3rd year mechanical engineering students were asked to write a total of more than 100 lines of C code, as part of their routine course assignments, during a single semester-long course on FEM.

… Continuing with the mechanical engineering students, why, even in the decidedly average (or below average) colleges in Mumbai and Pune, some kids (admittedly, may be only about 10% or 15% of them) can be found taking some extra efforts to learn some extra skills from the outside of our pathetic university system. Learning CAD/CAM/CAE software by attending private training institutes, has become a pretty wide-spread practice by now.

No, with these courses, they aren’t expected to become FEM/CFD experts, and they don’t. But at least they do learn to push buttons and put mouse-clicks in, say, ProE/SolidWorks or Ansys. They do learn to deal with conversions between different file formats. They do learn that meshes generated even in the best commercial software could sometimes be not of sufficiently high quality, or that importing mesh data into a different analysis program may render the mesh inconsistent and crash the analysis. Sometimes, they even come to master setting the various boundary condition options right—even if only in that particular version of that particular software. However, they wouldn’t be able to use a research level software like OpenFOAM on their own—and, frankly, it is not expected of them, not at their level, anyway.

They sometimes are also seen taking efforts on their own, in finding sponsorships for their BE projects (small-scale or big ones), sometimes even in good research institutions (like BARC). In fact, as far as the top quarter of the BE student projects (in the mechanical departments, in private engineering colleges) go, I often do get the definite sense that any lacunae coming up in these projects are not attributable so much to the students themselves as to the professors who guide these projects. The stories of a professor shooting down a good project idea proposed by a student simply because the professor himself wouldn’t have any clue of what’s going on, are neither unheard of nor entirely without merit.

So, yes, the overall trend even in the mechanical engineering stream is certainly dipping downwards, that’s for sure. Yet, the actual fall—its level—does not seem to be as bad as what is being reported about CS.

My two cents.

Today is India’s National Science Day. Greetings!

Will stay busy in moving and getting settled in the new job. … Don’t look for another post for another couple of weeks. … Take care, and bye for now.

[Finished doing minor editing touches on 28 Feb. 2017, 17:15 hrs.]

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# The goals are clear, now

This one blog post is actually a combo-pack of some 3 different posts, addressed to three different audiences: (i) to my general readers, (ii) to the engineering academics esp. in India, and (iii) to the QM experts. Let me cover it all in that order.

(I) To the general reader of this blog:

I have a couple of neat developments to report about.

I.1. First, and of immediate importance: I have received, and accepted, a job offer. Of course, the college is from a different university, not SPPU (Savitribai Phule Pune University). Just before attending this interview (in which I accepted the offer), I had also had discussions with the top management of another college, from yet another university (in another city). They too have, since then, confirmed that they are going to invite me once the dates for the upcoming UGC interviews at their college are finalized. I guess I will attend this second interview only if my approvals (the university and the AICTE approvals) for the job I have already accepted and will be joining soon, don’t go through, for whatever reason.

If you ask me, my own gut feel is that the approvals at both these universities should go through. Historically, neither of these two universities have ever had any issue with a mixed metallurgy-and-mechanical background, and especially after the new (mid-2014) GR by the Maharashtra State government (by now 2.5+ years old), the approval at these universities should be more or less only a formality, not a cause for excessive worry as such.

I told you, SPPU is the worst university in Maharashtra. And, Pune has become a real filthy, obnoxious place, speaking of its academic-intellectual atmosphere. I don’t know why the outside world still insists on calling both (the university and the city) great. I can only guess. And my guess is that brand values of institutions tend to have a long shelf life—and it would be an unrealistically longer shelf life, when the economy is mixed, not completely free. That is the broad reason. There is another, more immediate and practical reason to it, too—I mean, regarding how it all actually has come to work.

Most every engineer who graduates from SPPU these days goes into the IT field. They have been doing so for almost two decades by now. Now, in the IT field, the engineering knowledge as acquired at the college/university is hardly of any direct relevance. Hence, none cares for what academically goes on during those four years of the UG engineering—not in India, I mean—not even in IITs, speaking in comparison to what used to be the case some 3 decades ago. (For PG engineering, in most cases, the best of them go abroad or to IITs anyway.) By “none” I mean: first and foremost, the parents of the students; then the students themselves; and then, also the recruiting companies (by which, I mostly mean those from the IT field).

Now, once in the IT industry and thus making a lot of money, these people of course find it necessary to keep the brand value of “Pune University” intact. … Notice that the graduates of IITs and of COEP/VJTI etc. specifically mention their college on their LinkedIn profiles. But none from the other colleges in SPPU do. They always mention only “University of Pune”. The reason is, their colleges didn’t have as much of a brand value as did the university, when all this IT industry trend began. Now, if these SPPU-graduated engineers themselves begin to say that the university they attended was in fact bad (or had gone bad at least when they attended it), it will affect their own career growth, salaries and promotions. So, they never find it convenient to spell out the truth—who would do that? Now, the Pune education barons (not to mention the SPPU authorities) certainly are smart enough to simply latch on to this artificially inflated brand-value. The system works, even though the quality of engineering education as such has very definitely gone down. (In some respects, due to expansion of the engineering education market, the quality has actually gone up—even though my IIT/COEP classmates often find this part difficult to believe. But yes, there have been improvements too. The improvements pertain to such things as syllabii and systems (in the “ISO” sense of the term). But not to the actual delivery—not to the actually imparted education. And that‘s my point.)

When parents and recruiting companies themselves don’t care for the quality of education imparted within the four years of UG engineering, it is futile to expect that mere academicians, as a group, would do much to help the matters.

That’s why, though SPPU has become so bad, it still manages to keep its high reputation of the past—and all its current whimsies (e.g. such stupid issues as the Metallurgy-vs-Mechanical branch jumping, etc.)—completely intact.

Anyway, I am too small to fight the entire system. In any case, I was beyond the end of all my resources.

All in all, yes, I have accepted the job offer.

But despite the complaining/irritating tone that has slipped in the above write-up, I would be lying to you if I said that I was not enthusiastic about my new job. I am.

I.2. Second, and from the long-term viewpoint, the much more important development I have to report (to my general readers) is this.

I now realize that I have come to develop a conceptually consistent physical viewpoint for the maths of quantum mechanics.

(I won’t call it an “interpretation,” let alone a “philosophical interpretation.” I would call it a physics theory or a physical viewpoint.)

This work was in progress for almost a year and a half or more—since October 2015, if I go by my scribblings in the margins of my copy of Griffiths’ text-book. I still have to look-up the scribblings I made in the small pocket notebooks I maintain (more than 10 of them, I’ve finished already for QM alone). I also have yet to systematically gather and order all those other scribblings on the paper napkins I made in the restaurants. Yes, in may case, notings on the napkins is not just a metaphor; I have often actually done such notings, simply because sometimes I do forget to carry my pocket notebooks. At such times, these napkins (or those rough papers from the waiter’s order-pad), do come in handy. I have been storing them in a plastic bag, and a drawer. Once I look up all such notings systematically, I will be able to sequence the progression of my thoughts better. But yes, as a rough and ready estimate, thinking along this new line has been going on for some 1.5 years or more by now.

But it’s only recently, in December 2016 or January 2017, that I slowly grew fully confident that my new viewpoint is correct. I took about a month to verify the same, checking it from different angles, and this process still continues. … But, what the heck, let me be candid about it: the more I think about it, all that it does is to add more conceptual integrations to it. But the basic conceptual scheme, or framework, or the basic line of thought, stays the same. So, it’s it and that’s that.

Of course, detailed write-ups, (at least rough) calculations, and some (rough) simulations still have to be worked out, but I am working on them.

I have already written more than 30 pages in the main article (which I should now be converting into a multi-chapter book), and more than 50 pages in the auxiliary material (which I plan to insert in the main text, eventually).

Yes, I have implemented a source control system (SVN), and have been taking regular backups too, though I need to now implement a system of backups to two different external hard-disks.

But all this on-going process of writing will now get interrupted due to my move to the new job, in another city. My blogging too would get interrupted. So, please stay away from this blog for a while. I will try to resume both ASAP, but as of today, can’t tell when—may be a month or so.

I have changed my stance regarding publications. All along thus far, I had maintained that I will not publish anything in one of those “new” journals in which most every Indian engineering professor publishes these days.

However, I now realize that one of the points in the approvals (by universities, AICTE, UGC, NAAC, NBA, etc.) concerns journal papers. I have only one journal paper on my CV. Keeping the potential IPR issues in mind, all my other papers were written in only schematic way (the only exception is the diffusion paper), and for that reason, they were published only in the conference proceedings. (I had explicitly discussed this matter not just with my guide, but also with my entire PhD committee.) Of course, I made sure that all these were international conferences, pretty reputed ones, of pretty low acceptance rates (though these days the acceptance rates at these same conferences have gone significantly up (which, incidentally, should be a “good” piece of news to my new students)). But still, as a result, all but one of my papers have been only conference papers, not journal papers.

After suffering through UGC panel interviews at three different colleges (all in SPPU) I now realize that it’s futile to plead your case in front of them. They are insufferable in every sense; they stick to their guns. You can’t beat their sense of “quality,” as it were.

So, I have decided to follow their (I mean my UGC panel interviewers’) lead, and thus have now decided to publish at least three papers in such journals, right over the upcoming couple of months or so.

Forgive me if I report the same old things (which I had reported in those international conferences about a decade ago). I have been assured that conference papers are worthless and that no one reads them. Reporting the same things in journal papers should enhance, I guess, their readability. So, the investigations I report on will be the same, but now they will appear in the Microsoft Word format, and in international journals.

That’s another reason why my blogging will be sparser in the upcoming months.

That way, in the world of science and research, it has always been quite a generally accepted practice, all over the world, to first report your findings in conferences, seek your peers’ opinions on your work or your ideas, and then expand on (or correct on) the material/study, and then send it to journals. There is nothing wrong in it. Even the topmost physicists have followed precisely the same policy. … Why, come to think of it, the very first paper that ushered humanity into the quantum era itself was only a conference talk. In fact it was just a local conference, albeit in an advanced country. I mean Planck’s very first announcement regarding quantization. … So, it’s a perfectly acceptable practice.

The difference this time (I mean, in my, present, case) will be: I will contract on (and hopefully also dumb down) the contents of my conference papers, so as to match the level of the journals in which my UGC panel interviewers themselves publish.

No, the above was not a piece of sarcasm—at least I didn’t mean it, when I wrote it. I merely meant to highlight an objective fact. Given the typical length, font size, gaps in sections, and the overall treatment of the contents of these journals, I will have to both contract on and dumb down on my write-ups. … I will of course also add some new sentences here and there to escape the no-previous-publication clause, but believe me, in my case, that is a very minor worry. The important thing would be to match the level of the treatment, to use the Microsoft Word’s equation editor, and to cut down on the length. Those are my worries.

Another one of my worries is how to publish two journal papers—one good, and one bad—based on the same idea. I mean, suppose I want to publish something on the nature of the $\delta$ of the calculus of variations, in one of these journals. … Incidentally, I do think that what I wrote on this idea right here on this blog a little ago, is worth publishing even in a good journal, say in Am. J. Phys., or at least in the Indian journal “Resonance.” So, I would like to eventually publish it one of these two journals, too. But for immediately enhancing the number of journal papers on my CV, I should immediately publish a shorter version of the same in one of these new international journals too, on an urgent basis. Now the question is: what all aspects I should withhold for now. That is my worry. That’s why, the way my current thinking goes, instead of publishing any new material (say on the $\delta$ of CoV), I should instead simply recycle the already conference-published material.

One final point. Actually, I never did think that it was immoral to publish in such journals (I mean the ones in which my interviewers from SPPU publish). These journals do have ISSN, and they always are indexed in the Google Scholar (which is an acceptable indexing service even to NBA), and sometimes even in Scopus/PubMed etc. Personally, I had refrained from publishing in them not because I thought that it was immoral to do so, but rather because I thought it was plain stupid. I have been treating the invitations from such journals with a sense of humour all along.

But then, the way our system works, it does have the ways and the means to dumb down one and all. Including me. When my very career is at the stake, I will very easily and smoothly go along, toss away my sense of quality and propriety, and join the crowd. (But at least I will be open and forth-right about it—admitting it publicly, the way I have already done, here.)

So, that’s another reason why my blogging would be sparser over the upcoming few months, esp. this month and the next. I will be publishing in (those) journals, on a high priority.

(III) To the QM experts:

Now, a bit to QM experts. By “experts,” I mean those who have studied QM through university courses (or text-books, as in my case) to PG or PhD level. I mean, the QM as it is taught at the UG level, i.e., the non-relativistic version of it.

If you are curious about the exact nature of my ideas, well, you will have to be patient. Months, perhaps even a year, it’s going to take, before I come to write about it on my blog(s). It will take time. I have been engaged in writing about it for about a month by now, and I speak from this experience. And further, the matter of having to immediately publish journal papers in engineering will also interfere the task of writing.

However, if you are an academic in India (say a professor or even just a serious and curious PhD student of physics/chemistry/engg physics program, say at an IIT/IISc/IISER/similar) and are curious to know about my ideas… Well, just give me a call and let’s decide on a mutually convenient time to meet in person. Ditto, for academics/serious students of physics from abroad visiting India.

No, I don’t at all expect any academics in (or visiting) India to be that curious about my work. But still, theoretically speaking, assuming that someone is interested: just send me an email or call me to fix an appointment, and we will discuss my ideas, in person. We will work out at the black-board (better than working on paper, in my experience).

I am not at all hung up about maintaining secrecy until publication. It’s just that writing takes time.

One part of it is that when you write, people also expect a higher level of precision from you, and ensuring that takes time. Making general but precise statements or claims, on a most fundamental topic of physics—it’s QM itself—is difficult, very difficult. Talking to experts is, in contrast, easy—provided you know what you are talking about.

In a direct personal talk, there is a lot of room for going back and forth, jumping around the topics, hand-waving, which is not available in the mode of writing-by-one-then-reading-by-another. And, talking with experts would be easier for me because they already know the context. That’s why I specified PhD physicists/professors at this stage, and not, say, students of engineering or CS folks merely enthusiastic about QM. (Coming to humanity folks, say philosophers, I think that via this work, I have nothing—or next to nothing—to offer to their specialty.)

Personally, I am not comfortable with video-conferencing, though if the person in question is a serious academic or a reputed corporate/national lab researcher, I would sure give it a thought to it. For instance, if some professor from US/UK that I had already interacted with (say at iMechanica, or at his blog, or via emails) wants to now know about my new ideas and wants a discussion via Skype, I could perhaps go in for it—even though I would not be quite comfortable with the video-conferencing mode as such. The direct, in person talk, working together at the black-board, works best for me. I don’t find Skype comfortable enough even with my own class-mates or close personal relations. It just doesn’t work by me. So, try to keep it out.

For the same reason—the planning and the precision required in writing—I would mostly not be able to even blog about my new ideas. Interactions on blogs tends to introduce too many bifurcations in the discussion, and therefore, even though the different PoV could be valuable, such interactions should be introduced only after the first cut in the writing is already over. That’s why, the most I would be able to manage on this blog would be some isolated aspects—granted that some inconsistencies or contradictions could still easily slip in. I am not sure, but I will try to cover at least some isolated aspects from time to time.

Here’s an instance. (Let me remind you: I am addressing this part to those who have already studied QM through text-books, esp. to PhD physicists. I am not only referring to equations, but more importantly, I am assuming the context of a direct knowledge of how topics like the one below are generally treated in various books and references.)

Did you ever notice just how radical was de Broglie’s idea? I mean, for the electron, the equations de Broglie used were:

$E = \hbar \nu$ and $p = \hbar k$.

Routine stuff, do you say? But notice, in the special relativity, i.e. in the classical electrodynamics, the equation for the energy of a massive particle is:
$E^2 = (pc)^2 + (m_0 c^2)^2$

In arriving at the relation $p = \hbar k$, Einstein had dropped the second term ($m_0^2 c^4$) from the expression for energy because radiation has no mass, and so, his hypothetical particles also would carry no mass.

When de Broglie assumed that this same expression holds also for the electron—its matter waves—what he basically was doing was: to take an expression derived for a massless particle (Einstein’s quantum of light) as is, and to assume that it would apply also for the massive particle (i.e. the electron).

In effect, what de Broglie had ended up asserting was that the matter-waves of the electron had a massless nature.

Got it? See how radical—and how subtly (indirectly, implicitly) slipped in—is that suggestion? Have you seen this aspect highlighted or discussed this way in a good university course or a text-book on modern physics or QM? …

…QM is subtle, very subtle. That’s why working out a conceptually consistent scheme for it is (and has been) such a fun.

The above observation was one of my clues in working out my new scheme. The other was the presence of the classical features in QM. Not only the pop-science books but also text-books on modern physics (and QM) had led me to believe that what the QM represented was completely radical break from the classical physic. Uh-oh. Not quite.

QM, actually, is hybrid. It does have a lot of classical elements built into it, right in its postulates. I had come to notice this part and was uncomfortable with it—I didn’t have the confidence in my own observation; I used to think that when I study more of QM, I would be shown how these classical features fall away. That part never happened, not even as my further studies of QM progressed, and so, I slowly became more confident about it. QM is hybrid, full stop. It does have classical features built right in its postulates, even in its maths. It does not represent a complete break from the classical physics—not as complete a break as physicists lead you to believe. That was my major clue.

Other clues came as my grasp of the nature of the QM maths became better and firmer, which occurred over a period of time. I mean the nature of the maths of: the Fourier theory, the variational calculus, the operator theory, and the higher-dimensional spaces.

I had come to understand the Fourier theory via my research on diffusion, and the variational calculus, via my studies (and teaching!) of FEM. The operator theory, I had come to suspect (simply comparing the way people used to write in the early days of QM, and the way they now write) was not essential to the physics of the QM theory. So I had begun mentally substituting the operators acting on the wavefunction by just a modified wavefunction itself. … Hell, do you express a classical problem—say a Poisson equation problem or a Navier-Stokes problem—via operators? These days people do, but, thankfully, the trend has not yet made it to the UG text-books to a significant extent. The whole idea of the operator theory is irrelevant to physics—its only use and relevance is in maths. … Soon enough, I then realized that the wavefunction itself is a curious construct. It’s pointless debating whether the wavefunction is ontic or epistemic, primarily because the damn thing is dimensionless. Physicists always take care to highlight the fact that its evolution is unitary, but what they never tell you, never ever highlight, is the fact that the damn thing has no dimensions. Qua a dimensionless quantity, it is merely a way of organizing some other quantities that do have a physical existence. As to its unitary evolution, well, all that this idea says is that it is merely a weighting function, so to speak. But it was while teaching thermodynamics (in Mumbai in 2014 and in Pune in 2015) that I finally connected the variational principles with the operator theory, the thermodynamic system with the quantum system, and this way then got my breakthroughs (or at least my clues).

Yet another clue was the appreciation of the fact that the world is remarkably stable. When you throw a ball, it goes through the space as a single object. The part of the huge Hilbert space of the entire universe which represents the ball—all the quantum particles in it—somehow does not come to occupy a bigger part of that space. Their relations to each other somehow stay stable. That was another clue.

As to the higher-dimensional function spaces, again, my climb was slow but steady. I had begun writing my series of posts on the idea of space. It helped. Then I worked through higher-dimensional space. A rough-and-ready version of my understanding was done right on this blog. It was then that my inchoate suspicions about the nature of the Hilbert space finally began to fall in place. There is an entrenched view, viz., that the wavefunction is a “vector” that “lives” only in a higher-dimensional abstract space, and that the existence of the tensor product over the higher-dimensional space makes it in principle impossible to visualize the wavefunction for a multi-particle quantum system, which means, any quantum system which is more complex than the hydrogen atom (i.e. a single electron). Schrodinger didn’t introduce this idea, but when Lorentz pointed out that a higher-dimensional space was implied by Schrodinger’s procedure, Schrodinger first felt frustrated, and later on, in any case, he was unable to overcome this objection. And so, this part got entrenched—and became a part of the mathematicians’ myths of QM. As my own grasp of this part of the maths became better (and it was engineers’ writings on linear algebra that helped me improve my grasp, not physicists’ or mathematicians’ (which I did attempt valiantly, and which didn’t help at all)) I got my further clues. For a clue, see my post on the CoV; I do mention, first, the Cartesian product, and then, a tensor product, in it.

Another clue was a better understanding of the nonlinear vs. linear distinction in maths. It too happened slowly.

As to others’ writings, the most helpful clue came from the “anti-photon” paper by (the Nobel laureate) W. E. Lamb. Among the bloggers, I found some of the write-ups by Lubos Motl to be really helpful; also a few by Schlafly. Discussions on Scott Aaronson’s blog were useful to check out the different perspectives on the quantum problems.

The most stubborn problem for me perhaps was the measurement problem, i.e. the collapse postulate. But to say anything more about it right away would be premature—it would too premature, in fact. I want to do it right—even though I will surely follow the adage that a completed document is better than a perfect document. Perfection may get achieved only on collapse, but I happily don’t carry the notion that a good treatment on the collapse postulate has to be preceded by a collapse.

Though the conceptual framework I now have in mind is new, once it is published, it would not be found, I think, to be very radically new—not by the working physicists or the QM experts themselves anyway. …

.. I mean, personally speaking, when I for the first time thought of this new way of thinking about the QM maths, it was radically new (and radically clarifying) to me. (As I said, it happened slowly, over a period of time, starting, may be, from second half of 2015 or so if not earlier).

But since then, through my regular searches on the ‘net, I have found that other people have been suggesting somewhat similar ideas for quite some time, though they have been, IMO, not as fully consistent as they could have been. For example, see Philip Wallace[^]’s work (which I came across only recently, right this month). Or, see Martin Ligare[^]’s papers (which I ran into just last month, on the evening of 25th January, to be precise). … Very close to my ideas, but not quite the same. And, not as conceptually comprehensive, if that’s the right word to use for it.

My tentative plan as of now is to first finish writing the document (already 30+ pages, as I mentioned above in the first section). This document is in the nature of a conceptual road-map, or a position/research-program paper. Call it a white-paper sort of a document, say. I want to finish it first. Simultaneously, I will also try to do some simulations or so, and only then go for writing papers for (good) journals. … Sharing of ideas on this blog wouldn’t have to wait until the papers though; it could begin much earlier than that, in fact as soon as the position paper is done, which should be after a few months—say by June-July at the earliest. I will try to keep this position paper as brief as possible, say under 100 pages.

Let’s see how it all goes. I will keep you updated. But yes, the goals are clear now.

I wrote this lengthy a post (almost 5000 words) because I did want to get all these things from my mind and on to the blog. But since in the immediate future I would be busy in organizing for the move (right from hunting for a house/flat to rent, to deciding on what all stuff to leave in Pune for the time being and what all to take with me), to the actual move (the actual packing, moving, and unpacking etc.), I wouldn’t get the time to blog over the next 2–3 weeks, may be until it’s March already. Realizing it, I decided to just gather all this material, which is worth 3 posts, and to dump it all together in this single post. So, there.

Bye for now.

[As usual, a minor revision or two may be done later.]

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# See, how hard I am trying to become an Approved (Full) Professor of Mechanical Engineering in SPPU?—2

Remember the age-old decade-old question, viz.:

“Stress or strain: which one is more fundamental?”

I myself had posed it at iMechanica about a decade ago [^]. Specifically, on 8th March 2007 (US time, may be EST or something).

The question had generated quite a bit of discussion at that time. Even as of today, this thread remains within the top 5 most-hit posts at iMechanica.

In fact, as of today, with about 1.62 lakh reads (i.e. 162 k hits), I think, it is the second most hit post at iMechanica. The only post with more hits, I think, is Nanshu Lu’s, providing a tutorial for the Abaqus software [^]; it beats mine like hell, with about 5 lakh (500 k) hits! The third most hit post, I think, again is about sharing scripts for the Abaqus software [^]; as of today, it lags mine very closely, but could overtake mine anytime, with about 1.48 lakh (148 k) hits already. There used to be a general thread on Open Source FEM software that used to be very close to my post. As of today, it has fallen behind a bit, with about 1.42 lakh (142 k) hits [^]. (I don’t know, but there could be other widely read posts, too.)

Of course, the attribute “most hit” is in no fundamental way related to “most valuable,” “most relevant,” or even “most interesting.”

Yet, the fact of the matter also is that mine is the only one among the top 5 posts which probes on a fundamental theoretical aspect. All others seem to be on software. Not very surprising, in a way.

Typically, hits get registered for topics providing some kind of a practical service. For instance, tips and tutorials on software—how to install a software, how to deal with a bug, how to write a sub-routine, how to produce visualizations, etc. Topics like these tend to get more hits. These are all practical matters, important right in the day-to-day job or studies, and people search the ‘net more for such practically useful services. Precisely for this reason—and especially given the fact that iMechanica is a forum for engineers and applied scientists—it is unexpected (at least it was unexpected to me) that a “basically useless” and “theoretical” discussion could still end up being so popular. There certainly was a surprise about it, to me. … But that’s just one part.

The second, more interesting part (i.e., more interesting to me) has been that, despite all these reads, and despite the simplicity of the concepts involved (stress and strain), the issue went unresolved for such a long time—almost a decade!

Students begin to get taught these two concepts right when they are in their XI/XII standard. In my XI/XII standard, I remember, we even had a practical about it: there was a steel wire suspended from a cantilever near the ceiling, and there was hook with a supporting plate at the bottom of this wire. The experiment consisted of adding weights, and measuring extensions. … Thus, the learning of these concepts begins right around the same time that students are learning calculus and Newton’s  3 laws… Students then complete the acquisition of these two concepts in their “full” generality, right by the time they are just in the second- or third-year of undergraduate engineering. The topic is taught in a great many branches of engineering: mechanical, civil, aerospace, metallurgical, chemical, naval architecture, and often-times (and certainly in our days and in COEP) also electrical. (This level of generality would be enough to discuss the question as posed at iMechanica.)

In short, even if the concepts are so “simple” that UG students are routinely taught them, a simple conceptual question involving them could go unresolved for such a long time.

It is this fact which was (honestly) completely unexpected to me, at least at the time when I had posed the question.

I had actually thought that there would surely be some reference text/paper somewhere that must have considered this aspect already, and answered it. But I was afraid that the answer (or the reference in which it appears) could perhaps be outside of my reach, my understanding of continuum mechanics. (In particular, I knew only a little bit of tensor calculus—only that as given in Malvern, and in Schaum’s series, basically. (I still don’t know much more about tensor calculus; my highest reach for tensor calculus remains limited to the book by Prof. Allan Bower of Brown [^].)) Thus, the reason I wrote the question in such a great detail (and in my replies, insisted on discussing the issues in conceptual details) was only to emphasize the fact that I had no hi-fi tensor calculus in mind; only the simplest physics-based and conceptual explanation was what I was looking for.

And that’s why, the fact that the question went unresolved for so long has also been (actually) fascinating to me. I (actually) had never expected it.

And yes, “dear” Officially Approved Mechanical Engineering Professors at the Savitribai Phule Pune University (SPPU), and authorities at SPPU, as (even) you might have noticed, it is a problem concerning the very core of the Mechanical Engineering proper.

I had thought once, may be last year or so, that I had finally succeeded in nailing down the issue right. (I might have written about it on this blog or somewhere else.) But, still, I was not so sure. So, I decided to wait.

I now have come to realize that my answer should be correct.

I, however, will not share my answer right away. There are two reasons for it.

First, I would like it if someone else gives it a try, too. It would be nice to see someone else crack it, too. A little bit of a wait is nothing to trade in for that. (As far as I am concerned, I’ve got enough “popularity” etc. just out of posing it.)

Second, I also wish to see if the Officially Approved Mechanical Engineering Professors at the Savitribai Phule Pune University (SPPU)) would be willing and able to give it a try.

(Let me continue to be honest. I do not expect them to crack it. But I do wish to know whether they are able to give it a try.)

In fact, come to think of it, let me do one thing. Let me share my answer only after one of the following happens:

• either I get the Official Approval (and also a proper, paying job) as a Full Professor of Mechanical Engineering at SPPU,
• or, an already Officially Approved Full Professor of Mechanical Engineering at SPPU (especially one of those at COEP, especially D. W. Pande, and/or one of those sitting on the Official COEP/UGC Interview Panels for faculty interviews at SPPU) gives it at least a try that is good enough. [Please note, the number of hits on the international forum of iMechanica, and the nature of the topic, once again.]

I will share my answer as soon as either of the above two happens—i.e., in the Indian government lingo: “whichever is earlier” happens.

But, yes, I am happy that I have come up with a very good argument to finally settle the issue. (I am fairly confident that my eventual answer should also be more or less satisfactory to those who had participated on this iMechanica thread. When I share my answer, I will of course make sure to note it also at iMechanica.)

This time round, there is not just one song but quite a few of them competing for inclusion on the “A Song I Like” section. Perhaps, some of these, I have run already. Though I wouldn’t mind repeating a song, I anyway want to think a bit about it before finalizing one. So, let me add the section when I return to do some minor editing later today or so. (I certainly want to get done with this post ASAP, because there are other theoretical things that beckon my attention. And yes, with this announcement about the stress-and-strain issue, I am now going to resume my blogging on topics related to QM, too.)

Update at 13:40 hrs (right on 19 Dec. 2016): Added the section on a song I like; see below.

A Song I Like:

(Marathi) “soor maagoo tulaa mee kasaa? jeevanaa too tasaa, mee asaa!”
Lyrics: Suresh Bhat
Music: Hridaynath Mangeshkar
Singer: Arun Date

It’s a very beautiful and a very brief poem.

As a song, it has got fairly OK music and singing. (The music composer could have done better, and if he were to do that, so would the singer. The song is not in a bad shape in its current form; it is just that given the enormously exceptional talents of this composer, Hridaynath Mangeshkar, one does get a feel here that he could have done better, somehow—don’t ask me how!) …

I will try to post an English translation of the lyrics if I find time. The poem is in a very, very simple Marathi, and for that reason, it would also be very, very easy to give a rough sense of it—i.e., if the translation is to be rather loose.

The trouble is, if you want to keep the exact shade of the words, it then suddenly becomes very difficult to translate. That’s why, I make no promises about translating it. Further, as far as I am concerned, there is no point unless you can convey the exact shades of the original words. …

Unless you are a gifted translator, a translation of a poem almost always ends up losing the sense of rhythm. But even if you keep a more modest aim, viz., only of offering an exact translation without bothering about the rhythm part, the task still remains difficult. And it is more difficult if the original words happen to be of the simple, day-to-day usage kind. A poem using complex words (say composite, Sanskrit-based words) would be easier to translate precisely because of its formality, precisely because of the distance it keeps from the mundane life… An ordinary poet’s poem also would be easy to translate regardless of what kind of words he uses. But when the poet in question is great, and uses simple words, it becomes a challenge, because it is difficult, if not impossible, to convey the particular sense of life he pours into that seemingly effortless composition. That’s why translation becomes difficult. And that’s why I make no promises, though a try, I would love to give it—provided I find time, that is.

Second Update on 19th Dec. 2016, 15:00 hrs (IST):

A Translation of the Lyrics:

I offer below a rough translation of the lyrics of the song noted above. However, before we get to the translation, a few notes giving the context of the words are absolutely necessary.

Notes on the Context:

Note 1:

Unlike in the Western classical music, Indian classical music is not written down. Its performance, therefore, does not have to conform to a pre-written (or a pre-established) scale of tones. Particularly in the Indian vocal performance, the singer is completely free to choose any note as the starting note of his middle octave.

Typically, before the actual singing begins, the lead singer (or the main instrument player) thinks of some tone that he thinks might best fit how he is feeling that day, how his throat has been doing lately, the particular settings at that particular time, the emotional interpretation he wishes to emphasize on that particular day, etc. He, therefore, tentatively picks up a note that might serve as the starting tone for the middle octave, for that particular performance. He makes this selection not in advance of the show and in private, but right on the stage, right in front of the audience, right after the curtain has already gone up. (He might select different octaves for two successive songs, too!)

Then, to make sure that his rendition is going to come out right if he were to actually use that key, that octave, what he does is to ask a musician companion (himself on the stage besides the singer) to play and hold that note on some previously well-tuned instrument, for a while. The singer then uses this key as the reference, and tries out a small movement or so. If everything is OK, he will select that key.

All this initial preparation is called (Hindi) “soor lagaanaa.” The part where the singer turns to the trusted companion and asks for the reference note to be played is called (Hindi) “soor maanganaa.” The literal translation of the latter is: “asking for the tone” or “seeking the pitch.”

After thus asking for the tone and trying it out, if the singer thinks that singing in that specific key is going to lead to a good concert performance, he selects it.

At this point, both—the singer and that companion musician—exchange glances at each other, and with that indicate that the tone/pitch selection is OK, that this part is done. No words are exchanged; only the glances. Indian performances depend a great deal on impromptu variations, on improvizations, and therefore, the mutual understanding between the companion and the singer is of crucial importance. In fact, so great is their understanding that they hardly ever exchange any words—just glances are enough. Asking for the reference key is just a simple ritual that assures both that the mutual understanding does exist.

And after that brief glance, begins the actual singing.

Note 2:

Whereas the Sanskrit and Marathi word “aayuShya” means life-span (the number of years, or the finite period that is life), the Sanskrit and Marathi word “jeevan” means Life—with a capital L. The meaning of “jeevan” thus is something like a slightly abstract outlook on the concrete facts of life. It is like the schema of life. The word is not so abstract as to mean the very Idea of Life or something like that. It is life in the usual, day-to-day sense, but with a certain added emphasis on the thematic part of it.

Note 3:

Here, the poet is addressing this poem to “jeevan” i.e., to the Life with a capital L (or the life taken in its more abstract, thematic sense). The poet is addressing Life as if the latter is a companion in an Indian singing concert. The Life is going to help him in selecting the note—the note which would define the whole scale in which to sing during the imminent live performance. The Life is also his companion during the improvisations. The poem is addressed using this metaphor.

Now, my (rough) translation:

The Refrain:
[Just] How do I ask you for the tone,
Life, you are that way [or you follow some other way], and I [follow] this way [or, I follow mine]

Stanza 1:
You glanced at me, I glanced at you,
[We] looked full well at each other,
Pain is my mirror [or the reference instrument], and [so it is] yours [too]

Stanza 2:
Even once, to [my] mind’s satisfaction,
You [oh, Life] did not ever become my [true]  mate
[And so,] I played [on this actual show of life, just whatever] the way the play happened [or unfolded]

And, finally, Note 4 (Yes, one is due):

There is one place where I failed in my translation, and most any one not knowing both the Marathi language and the poetry of Suresh Bhat would.

In Marathi, “tu tasaa, [tar] mee asaa,” is an expression of a firm, almost final, acknowledgement of (irritating kind of) differences. “If you must insist on being so unreasonable, then so be it—I am not going to stop following my mind either.” That is the kind of sense this brief Marathi expression carries.

And, the poet, Suresh Bhat, is peculiar: despite being a poet, despite showing exquisite sensitivity, he just never stops being manly, at the same time. Pain and sorrow and suffering might enter his poetry; he might acknowledge their presence through some very sensitively selected words. And yet, the underlying sense of life which he somehow manages to convey also is as if he is going to dismiss pain, sorrow, suffering, etc., as simply an affront—a summarily minor affront—to his royal dignity. (This kind of a “royal” sense of life often is very well conveyed by ghazals. This poem is a Marathi ghazal.) Thus, in this poem, when Suresh Bhat agrees to using pain as a reference point, the words still appear in such a sequence that it is clear that the agreement is being conceded merely in order to close a minor and irritating part of an argument, that pain etc. is not meant to be important even in this poem let alone in life. Since the refrain follows immediately after this line, it is clear that the stress gets shifted to the courteous question which is raised following the affronts made by one fickle, unfaithful, even idiotic Life—the question of “Just how do I treat you as a friend? Just how do I ask you for the tone?” (The form of “jeevan” or Life used by Bhat in this poem is masculine in nature, not neutral the way it is in normal Marathi.)

I do not know how to arrange the words in the translation so that this same sense of life still comes through. I simply don’t have that kind of a command over languages—any of the languages, whether Marathi or English. Hence this (4th) note. [OK. Now I am (really) done with this post.]

Anyway, take care, and bye for now…

Update on 21st Dec. 2016, 02:41 AM (IST):

Realized a mistake in Stanza 1, and corrected it—the exchange between yours and mine (or vice versa).

[E&OE]

/

# See, how hard I am trying to become a (Full) Professor of Mechanical Engineering in SPPU?

Currently, I am not only cashless but also jobless. That’s why, I try harder.

I am trying very hard to be a (Full) Professor of Mechanical Engineering, especially at the Savitribai Phule Pune University (or SPPU for short).

That’s right.

And that’s why, I have decided to adopt an official position whereby I abandon all my other research and study interests, especially those related to the mechanics of the quanta. Instead, I have officially decided to remain interested only in the official problems from the Mechanical Engineering discipline proper—not only for my studies, but also for my research interests.

… If only I were to have my first degree in Mechanical Engineering, instead of in Metallurgy! (It was some 37.5–33.5 years ago, with my decision to choose Metallurgy being from some 36.5 years ago.) … If only I were to choose Mechanical right back then, this problem wouldn’t have arisen today. …

Tch! …

…But, well, thinking of my first degree, its circumstances—where I got it from (COEP, the engineering college with the highest cut-off merit in the entire Maharashtra state), in what class (First Class with Distinction, the highest class possible), and, most crucially, for spending all my time at what place (The Boat Club)… You know, looking back some 3.5 decades later of all those circumstances—the circumstances of how I chose Metallurgy, back then, as I was sitting at the Boat Club… Hmmm… Boat Club. … Boat Club! Boat Club!!

It gives me some ideas.

So, to better support my current endeavors of becoming an Officially Approved Full Professor of Mechanical Engineering in SPPU, may be, I should solve some Mechanical Engineering problems related to boats. Preferably, those involving not just fluid mechanics, but also mechanisms and machine design—and vibrations! [Oh yes. I must not forget them! Vibrations are, Officially, a Mechanical Engineering topic. In fact even Acoustics. …]

Thinking along such lines, I then thought of one problem, and sort of solved it too. Though I am not going to share my answer with you, I certainly want to share the problem itself with you. (Don’t ask me for answers until I get the job as an Officially Approved Full Professor in Mechanical Engineering at SPPU.)

OK, so here we go.

The Problem Description:

Consider a boat floating on a stand-still lake. The boat has a very simple shape; it is in the shape of a rectangular parallelpiped (i.e., like a shoe-box, though not quite exactly like a punt).

In the plan (i.e. the top view), the boat looks like this:

As shown in the figure, at the centers of the front- and back-sides of the boat, there are two circular cylindrical cavities of identical dimensions, both being fitted with reciprocating pistons. These pistons are being driven by two completely independent mechanisms. The power-trains and the prime-movers are not shown in the diagram; in this analysis, both may be taken to be mass-less and perfectly rigid. However, the boat is assumed to have some mass.

We will try to solve for the simplest possible case: perfectly rigid boat walls (with some mass), perfectly rigid but mass-less pistons, complete absence of friction between the pistons and the cylinder walls, etc.

Assume also that both the boat and the lake water are initially stand-still, and that there are no other influences affecting the motions (such as winds or water currents).

Now, let’s put the pistons in oscillatory motions. In general, the frequencies of their oscillations are not equal. Let the frequency for the left- and right-side pistons be $f_L$ and $f_R$ Hz, respectively.

Problem 1:

Build a suitable Mechanical Engineering model, and predict how the boat would move, in each of the following three scenarios:

• $f_L = f_R$
• $f_L > f_R$
• $f_L < f_R$

In each case, determine (i) whether the boat as a whole (i.e. its center of mass or CM) would at all undergo any motion at all or not, (ii) if yes, whether the motion of the CM would have an element of oscillations to it or not, and finally, (iii) whether the boat (i.e. its CM) would undergo a net displacement over a large number of pistons oscillations or not (i.e., the question asks whether the so-called “time-averaged” net displacement occurs in any one direction or not), and if yes, in which direction.

You may make other minor assumptions. For instance, in each of the above 3 cases, you may assume that at time $t = 0$, both the pistons are at their innermost positions, with each piston beginning its motion by pushing outwards. Also check out the effect of assuming, some other, suitable, values for the initial phases.

Though not at all necessary, if it will help you, you may perhaps consider the case where the higher frequency is an integer multiple of the lower frequency, e.g., in the second of the three cases, assume $f_L = n f_R$, where $n \in \mathcal{N}$. However, note that eventually, you are expected to solve the problem in the general case, the one in which the ratio of the frequencies may be any real number. The cases of practical interest may be where the ratio ranges from 0.0 to a real number up to, say, 2.67 or 3.14 (or, may be, 5.25).

Notice that nowhere thus far have we said that the oscillatory motion of the pistons would be SHM (i.e. simple harmonic). You may begin with an SHM, but as a further problem below illustrates, the piston motion may neither be simple-harmonic, nor even symmetrical in the to- and fro-directions.

On the fluid mechanics side: In your analysis, assume that the length of the boat is much, much greater than the stroke-lengths of the pistons. Essentially, we want to ensure that the water waves produced at one end do not significantly affect the local dynamics at the other end.

You may assume a highly simplified model for the fluid—the problem is not supposed to have a crucial bearing on what kind of a fluid you assume. I mean to say, we are not looking for so detailed a model that you would have to perform a CFD analysis. (That task, we will leave to the Naval Architecture engineers.) However, do make sure to note how your model behaves for an inviscid flow vs. for a viscous flow.

So, in short, the problem is to determine the nature of the motion of the boat, if there is any—i.e., to determine if its CM undergoes a net displacement in the time-averaged sense or not, and if yes, in which direction it occurs.

Problem 2:

Assume a relatively smaller stroke-length for one of the pistons, and repeat the problem.

Problem 3:

Assume that one of the frequencies is zero, which is as good as saying that the boat is fitted with only one cylinder-and-piston. Repeat the analysis.

Problem 4:

Continue to assume that one of the frequencies is zero. Now, also assume that the outward stroke of the moving piston happens faster than its inward stroke. Determine the nature of the motion, if any, for the CM of the boat.

Problem 5 (Optional):

Assuming that the prime mover outputs a uniform circular (or rotary) motion, design a suitable mechanism which will help implement the idea of having non-SHM motions—e.g., different stroke-times in the outward and inward directions. Conduct an informal (or a more formal, calculus-based) displacement-, velocity- and acceleration-analysis, if you wish.

Give it a thought whether this entire idea of transforming a circular motion to a nonuniform reciprocating motion can be done away with, thereby saving on energy—in real life, there is friction—using certain ideas from electrical engineering and electronics.

Ooops!

No, no, no! No!! Throw out that horrendous idea! I mean the very last one!!

We want to remain concerned only with the Mechanical Engineering Problems proper. That is the Official position I have adopted, remember?

That’s right. What I described above was, really, really, really only a Mechanical Engineering Problem.

It really, really, really has nothing to do with anything else such as electrical engineering or quantum physics.

[And if even Prof. Thanu Padmanabhan (IUCAA) does not know quantum physics (he told me so once, right in person), why should I be concerned with it, anyway?]

Anyway, so, Officially speaking, I made up this problem only because I want to become an Officially Approved Full Professor of Mechanical Engineering at SPPU.

If you are interested in some other Mechanical Engineering problems, especially on the fluids-thermal side, check out my recent posts on the Eco-Cooler, and see if you can take further the analysis given in them.

I myself had made a much more advanced engineering analysis right at that time, but I am not going to give it—or its results—until some time after I land and join the kind of job I am looking for—a Full Professor’s. (And I hope that you do have the sense to see that this is not a “prestige issue” on my part.)

The post having a preliminary (quantitative) fluids-thermal analysis is here [^], though the qualitative analysis of the problem begins with an earlier post, here [^].

[Guess the problem, as given, is enough for the time being. I may even come back and add one or two variations on the problem! But no guarantees.]

Update right on 2016.12.02: OK, here are a couple of minor variations. What happens if, when a piston comes to a rest at the extreme stroke, it continues staying idle for a while, before resuming its towards-the-center motion? What if the piston motion is such that the point of zero displacement does not occur exactly at the middle of its overall stroke-length?

I may post some further variations on the problem, or suggest alternative analogous problems, in future.

Currently, I am not just cashless but also jobless. That’s why, I try harder.

More, may be later. As to the Song I Like section, I don’t have anything playing at the back of my mind right away, so let me see if something strikes me by the time I come back tomorrow to give a final editing touch to this post. In that case, I will add this section; else, I will not!

[After the update right on 2016.12.02: I am done with this post now, and if there are any errors, I will let them stay. If you find the post confusing somewhere, please do drop me a line, though. Best, and take care.]

[E&OE]

# Miscellaneous: books to read, a new QM journal, the imposter syndrome, the US presidential elections

While my mood of not wanting to do anything in particular still continues (and also, there is no word yet on the job-related matters, including on whether I might qualify as a Professor of Mechanical Engineering in SPPU or not), there are a few quick things that I may as well note.

Updates on 17th, 18th and 22nd Nov. 2016: See my English translation[s] of the song, at the end of the post.

First, the books to read. Here are a few books on my to-read list:

1. Sean Carroll, “The Big Picture” [^]. I have been browsing through Sean’s blog-posts since before the time the book was published, and so have grown curious. I don’t have the money to buy it, right now, but once I get the next job, I sure plan to buy it. Here is the review in NY Times [^]. And, here is a latest review, written by a software engineer (whose link appeared in Sean’s twitter feed (I don’t myself use my Twitter account, but sometimes do check out the feeds of others via browser))[^]. Judging from his posts, I do know that Sean writes really well, and I would certainly want to check out this book, eventually.
2. Roger Penrose, “Fashion, Faith, and Fantasy in the New Physics of the Universe,” [^]. This is the latest offering by Penrose. Sometimes I simply type “quantum physics” in Google, and then, in the search results, I switch the tab over to “news.” I came to know of this book via this route, last week, when I ran into this review [^].
3. Roger Schlafly, “How Einstein Ruined Physics: Motion, Symmetry and Revolution in Science,” [^]. Here is a review [^], though my curiosity about the book rests not on the review but on two things: (i) what I had thought of Einstein myself, as far back as in early 1990s, while at UAB (hint: Schlafly’s thesis wouldn’t be out of bounds for me), and (ii) my reading the available portions of the book at Google Books. …This book has been on my “to-read” list for quite some time, but somehow it keeps slipping off. … Anyway, to be read, soon after I land a job…

A New QM Journal:

A new journal has arrived on the QM scene: [^]. Once again, I got to know of it through the “news” tab in a Google search on “quantum physics”, when I took this link [^].

It’s an arXiv-overlay journal. What it means is that first you submit your paper to arXiv. … As you know, getting something published at arXiv carries a pretty low bar (though it is not zero, and there have been some inconsistencies rarely reported about improper rejections even at arXiv). It’s good to bring your work to the notice of your peers, but it carries no value in your academic/research publications record, because arXiv is not a proper journal as such. … Now, if your work is good, you want to keep it open-access, but you don’t want to pay for keeping it open-access, and, at the same time, you also want to have the credentials of a proper journal publication to your credit, you have a solution, in the form of this arXiv-overlay journal. You send the link to your arXiv-published paper to them. If their editorial board finds it fitting the standards and purpose of their journal, they will include it.

The concept originated, I guess, with Timothy Gowers [^] and others’ efforts, when they started a maths journal called “Discrete Analysis.” At least I do remember reading about it last year [^]. Here is Gowers’ recent blog post reflecting on the success of this arXiv-overlay journal [^]. Here is what Nature had to report about the movement a few months ago [^].

How I wish there were an arXiv for engineering sciences too.

Especially in India, there has been a proliferation of bad journals: very poor quality, but they carry an ISSN, and they are accepted as journals in the Indian academia. I don’t have to take names; just check out the record of most any engineering professor from outside the IISc/IIT system, and you will immediately come to know what I mean.

At the same time, for graduate students, especially for the good PhD students who happen to lie outside the IIT system (there are quite a few such people), and for that matter even for MTech students in IITs, finding a good publication venue sometimes is difficult. Journal publications take time—1 or 2 years is common. Despite its size, population, or GDP, India hardly has any good journals being published from here. At the same time, India has a very large, sophisticated, IT industry.

Could this idea—arXiv-overlay journal—be carried into engineering space and in India? Could the Indian IT industry help in some ways—not just technical assistance in creating and maintaining the infrastructure, but also by way of financial assistance to do that?

We know the answer already in advance. But what the hell! What is the harm in at least mentioning it on a blog?

Just an Aside (re. QM): I spent some time noting down, on my mental scratch-pad, how QM should be presented, and in doing so, ended up with some rough outlines of  a new way to do so. I will write about it once I regain enough levels of enthusiasm.

The Imposter Syndrome:

It seems to have become fashionable to talk of the imposter syndrome [^]. The first time I read the term was while going through Prof. Abinandanan’s “nanopolitan” blog [^]. Turns out that it’s a pretty widely discussed topic [^], with one write-up even offering the great insight that “true imposters don’t suffer imposter syndrome” [^]. … I had smelled, albeit mildly, something like a leftist variety of a dead rat here… Anyway, at least writing about the phenomenon does seem to be prevalent among science-writers; here is a latest (H/T Sean Carroll’s feed) [^]…

Anyway, for the record: No, I have not ever suffered from the imposter syndrome, not even once in my life, nor do I expect to do so in future.

I don’t think the matter is big enough for me to spend any significant time analyzing it, but if you must (or if you somehow do end up analyzing it, for whatever reasons), here is a hint: In your work, include the concept of “standards,” and ask yourself just one question: does the author rest his standards in reason and reality, or does he do so in some people—which, in case of the imposter syndrome, would be: the other people.

Exercise: What (all) would stand opposite in meaning to the imposter syndrome? Do you agree with the suggestion here [^]?

The US Presidential Elections: Why are they so “big”? should they be?

Recently, I made a comment at Prof. Scott Aaronson’s blog, and at that time, I had thought that I would move it here as a separate post in its own right. However, I don’t think I have the energy right now, and once it returns, I am not sure if it will not get lost in the big stack of things to do. Anyway, here is the link [^]. … As I said, I am not interested much—if at all—in the US politics, but the question I dealt with was definitely a general one.

Overall, though, my mood of boredom continues… Yaawwwnnnn….

A Song I Like:

(Hindi) “seene mein jalan…”
Lyrics: Shahryar
Music: Jaidev

[Pune today is comparable to the Bombay of 1979 1978—but manages to stay less magnificent.]

Update on 2016.11.17: English translation of the song:

For my English blog-readers: A pretty good translation of the lyrics is available at Atul’s site; it is done by one Sudhir; see here [^]. This translation is much better than the English sub-titles appearing in this YouTube video [^] which comes as the first result when you google for this song. …

I am not completely happy with Sudhir’s translation (on Atul’s site) either, though it is pretty good. At a couple of places or so, it gives a slightly different shade of meaning than what the original Urdu words convey.

For instance, in the first stanza, instead of

“Just for that there is a heart inside,
one searches a pretext to be alive,”

it should be something like:

“just because there is a heart,
someone searches (i.e., people search) for an excuse which can justify its beating”

Similarly, in the second stanza,  instead of:

“what is this new intensity of loneliness, my friend?”,

a more accurate translation would be:

“what kind of a station in the journey of loneliness is this, my friends?”.

The Urdu word “manzil” means: parts of the Koran, and then, it has also come to mean: a stage in a journey, a station, a destination, or even a floor in a multi-storied building. But in no case does it mean intensity, as such. The underlying thought here is something like this: “loneliness is OK, but look, what kind of a lonely place it is that I have ended up in, my friends!” And the word for “friend” appears in the plural, not the singular. The song is one of a silent/quiet reflection; it is addressed to everyone in general and none in particular.

… Just a few things like that, but yes, speaking overall, Sudhir’s translation certainly is pretty good. Much better than what I could have done purely on my own, and in any case, it is strongly recommended. … The lyrics are an indispensable part of the soul of this song—in fact, the song is so damn well-integrated, all its elements are! So, do make sure to see Sudhir’s translation, too.

Update on 2016.11.18: My own English translation:

I have managed to complete my English translation of the above song. Let me share it with you. I benefitted a great deal from Sudhir’s translation and notes about the meanings of the words, mentioned in the note above, as well as further from “ek fankaar” [^]. My translation tries to closely follow not only the original words but also their sequence. To maintain continuity, the translation is given for the entire song as a piece.

First, the original Hindi/Urdu words:

seene mein jalan aankhon mein toofaan sa kyun hai
is shehar mein har shakhs pareshaan saa kyun hai

dil hai to dhadakne ka bahaanaa koi dhoondhe
patthar ki tarah behis-o-bejaan sa kyun hai

tanahaai ki ye kaun si manzil hai rafeeqon
ta-hadd-e-nazar ek bayaabaan saa kyon hai

kyaa koi nai baat nazar aati hai ham mein
aainaa hamen dekh ke hairaan sa kyon hai

Now, my English translation, with some punctuation added by me [and with further additions in the square brackets indicating either alternative words or my own interpolations]:

Why is there jealousy in the bosom; a tempest, as it were, in the eyes?
In this city, every person—why does it seem as if he were deeply troubled [or harassed]?

[It’s as if] Someone has a heart, so he might go on looking for an alibi [or a pretext] to justify [keeping it] beating
[But] A stone, as if it were that, why is it so numb and lifeless [in the first place]?

What kind of a station in the journey of the solitude is this, [my noble] friends?
Right to the end of the sight, why is there [nothing but] a sort of a total desolation?

Is there something new that has become visible about me?
The mirror, looking at me, why does it seem so bewildered [or perplexed]?

Update on 22nd Nov. 2016: OK, just one two more iterations I must have; just a slight change in the second [and the first [, and the third]] couplet[s]. (Even if further improvements would may be possible, I am now going to stop my iterations right here.):

Why is there jealousy in the bosom; a tempest, as it were, in the eyes?
In this city, every silhouette [of a person]—why does it seem as if he were deeply troubled [or harassed]?

[It’s as if] A heart, one does have, and so, someone might go on looking for an alibi [or a pretext] to justify [keeping it] beating
[But] A stone, as if it were that, why is it so numb and lifeless [in the first place]?

What kind of a station in the journey of the solitude is this, [my noble] friends?
[That] Right to the end of the sight, why is there [nothing but] a sort of a total desolation?

Is there something new that has become visible about me?
The mirror, looking at me, why does it seem so bewildered [or perplexed]?

[E&OE]

# What are the rules for hiring?—2

Last year in August, I had written a post of the title: “What are the rules for hiring?” [^]. In that post, I had pointed out that historically, the University of Pune (now called Savitribai Phule Pune University, or SPPU for short), in fact didn’t have this “Mechanical-vs-Metallurgy `Branch-Jumping’ Issue.” Though I have a BE in Metallurgy, I myself had taken admission, right in COEP, for an ME program in Mechanical Engineering.

In that post, I had also traced in some detail how COEP had thrown obstacles in my path at the time of my admission to the PhD program in Mechanical Engineering. (If you found (or now find) reading through all those details exasperating, then take a moment to realize what it might have been like for me to live through those artificially created struggles.)

Today, in this post, I once again return to the issue of the hiring rules. I want to provide the reader with copies of the relevant official documents, together with some discussion of the issues as well as my comments.

(I) The AICTE Norms:

If you do ‘net searches to find the AICTE norms document which governs the hiring of professors in the engineering colleges in this country, then you will find many documents floated by different colleges or universities. Most of the matter in such documents are similar to the actual AICTE document, though there often are some small and subtle differences. I don’t mind if different colleges/universities wish to follow policies that are at a slight variance from the norms issued by the AICTE. After all, these are norms, not hard-and-fast rules. To me, trouble begins only when they don’t explicitly note the points of departure. Go ahead, do ‘net searches, and you will find that not a single one of these unofficial documents has bothered to explicitly identify the changes they made from the original AICTE document.

For my purposes, I was looking for the original and authentic AICTE document. I found it faithfully uploaded at SPPU’s Web site, here [^]. Since the college/university Web sites sometimes fail to maintain all the documents or links in order, I have decided to keep a copy of this same document also on my Google Drive, here [^].

See Serial Number 3 on page 2 for Professor’s position in this document. It states:

“Ph.D  degree  with  first  class  degree  at  Bachelor’s  or  Master’s  level  in  the appropriate  branch  of  Engineering  /  Technology  with  10  years  experience in Teaching / Industry / Research out of which 5 years must be at the level of  Assistant  Professor  and  /  or  equivalent.”

True to the khaki register-style dumbness (or the (Marathi) “khaa kee!” type of “smart”ness), this wording is vague on multiple counts. (If there is someone intending to get bribes, let me state it, publicly, that I am refusing to give them any.)

You can interpret this wording in several different ways. The different interpretations can be had by mentally inserting braces “{}” to isolate the different blocks of the text together, and then working out whether these blocks of text apply multiplicatively (as in the Cartesian product) or not.

The two relevant and entirely different ways in which the wording can be interpreted is this:

Interpretation 1.0:

This interpretation says that: you should have a PhD degree in the appropriate branch + you should have a first class either at bachelor’s level or at the master’s level, but both the bachelor’s and the master’s degrees must have come only in the appropriate branch.

According to this interpretation, you are allowed to be dumb (you have to somehow manage a first class only once), so long as you have been conforming to the same branch throughout your life.

With this interpretation, the following issue arises: What does constitute an appropriate branch?

1.1 One sub-interpretation is: Only the Mechanical branch is the appropriate branch for the position of Professor of Mechanical Engineering.

1.2 The other sub-interpretation is: You may have the Mechanical branch either at the bachelor’s or the master’s level (just the way you can have a first class either at bachelor’s or master’s level) but not necessarily at both.

Since I didn’t have a Mechanical degree at either bachelor’s or master’s level, I couldn’t qualify, according to this interpretation 1.0 (whether you follow 1.1 or 1.2).

Interpretation 2.0:

This interpretation says that: You should have a PhD degree in the appropriate branch + you should have a first class either at bachelor’s level or at the master’s level, and further, that either bachelor’s or master’s degrees should have come from an appropriate branch.

Once again, you have to decide what constitutes an appropriate branch.

2.1 One sub-interpretation is: Only the Mechanical branch is the appropriate branch for a position of Professor of Mechanical Engineering.

2.1 The other sub-interpretation is: There can be choices for the appropriate branch at any of the degrees. For instance, to become a Professor of Mechanical Engineering, all the following are OK:
BE (Mech) + ME (Mech) + PhD (Met.)
BE (Mech) + ME (Prod) + PhD (Prod)
BE (Prod) + ME (Prod) + PhD (Prod)
BE (Met) + MTech (Met) + PhD (Mech)—my combination
BE (Aero) + ME (Met) + PhD (Met.)
Etc.

This was my interpretation. It makes sense, because: (i) the wording is: “Bachelor’s or Master’s level in the appropriate branch,” and (ii) the word used is: “the appropriate branch,” not “the same branch.”

The Malady: The interpretation 1.0 was what was adopted by the former Dean of Faculty of Engineering at SPPU, i.e., Dr. G. K. Kharate.

End of (this part of the) story.

(II) The Mumbai University Norms (2012):

The Mumbai University historically had always followed the interpretation 2.2, and never had major issues.

However, in view of the tightening of the government controls, they had held detailed discussions, and then had arrived at an explicit document that clearly states what all constitute the appropriate branches. They published this decision via a document called “Circular No. CONCOL/ICC/04/ of 2012”. I once again link to a copy that I have stored on my Google Drive, here [^].

See page 2 of this document, for the statement qualifications for an Assistant Professor:

“BE/ B Tech and ME /M Tech in relevant subject with First Class or equivalent either in BE / B Tech or ME / M Tech OR ME/M TECH in relevant Subject with First Class”

See page 3 of the same document for additional qualifications for an Associate Professor:

“Qualification as above that is for the post of Assistant Professor, as applicable and PHD or equivalent, in appropriate Discipline”

On the same page, certain additional qualifications expected for a Professor’s position are noted.

See page 9, Serial No. 2 of this document. For a position of Professor in Mechanical Engineering, Metallurgy is included as an equivalent/relevant/appropriate branch, even though only at the master’s level.

However, the drafting is extraordinarily clear here—there are two “or”s—one in the lowercase letters, and another in the capitals. The existence of the capital “OR” makes it abundantly clear that having only a master’s in a relevant subject with First Class is good enough. [Little wonder that the University of Mumbai always cuts ahead of the SPPU on rankings.]

As such, Interpretation 2.2 applies, and I qualify.

I anyway met with their Dean, had it clarified that I indeed do qualify, and eventually, was offered jobs as a Professor of Mechanical Engineering. See my resume regarding these jobs. (The particular link to my resume may change as I update the resume, but it is always accessible from the home page of my personal Web site [^].)

But then, of course, the University of Pune (now SPPU) believes that they are the best and the most conscientious (or least licentious) in the world. So, they were never going to be taken in by the mere fact that the University next door (one which has always been ranked higher by every agency in the world) did easily allow me to function as an employed Professor of Mechanical Engineering. (I anyway do function as a professor of engineering. The only question is: whether they allow me to get employed as one, or not. The lower-ranked SPPU’s geniuses don’t.)

III The Maharashtra State GR (May 2014):

Sorry, on two counts: (i) I cannot give you a direct link to this document at the Web sites of the Maharashtra State Government. I found this document at the Recruitments section of COEP’s Web site, in June 2015, but the document is no longer to be found even at the COEP Web site. (ii) The document is in Marathi, so, my English readers would have to trust me when it comes to the titles of the columns of the relevant table.

Though the GR had come in effect in May 2014, I came to know of it only in June of 2015. The utmost benevolent Mechanical Engineering Professors (and the authorities) at SPPU are still napping dozing off, still getting annoyed when I mention the GR, and still asking me for a copy of this document (with a “knowing” certainty that they would be able to disqualify me in reference even to this GR).

I have once again uploaded my copy of the document to Google Drive, here [^].

Refer to page 13, Serial Number 2. (Fortunately, the Arabic numerals in English and in Marathi are quite similar, because the so-called Arabic numerals had originated in India anyway.)

At the master’s level, the GR expands on even the Mumbai Universities’ list of the equivalent/relevant/appropriate branches (though it cuts down on the Aerospace engineering at the bachelor’s level).

Showing this document, my last employers did offer me a position of Professor in Mechanical Engineering. (No, they didn’t give me the UGC scale. But they did offer me a full Professor’s position—and later on, treated me with full organizational respect that goes with a full Professor’s position.) I even uploaded the internal marks to SPPU’s BCUD Web site, using my own official account.)

Even then, even this year, the Mechanical Engineering geniuses and other employers at the utmost conscientious SPPU are still telling me that I don’t qualify.

As to my last employers, though their college is in Pune and is affiliated to SPPU, their headquarters are in Nagpur, not in Pune. But then, my point is, you don’t have to go so far away as to Nagpur. Go just 75 kms from this filthy place, and as soon as you climb down the Khandala ghat (and with that, also shed your obnoxious conformism of a mindless sort), and you reach a better place.

The Rules for the Maharashtra State Government’s Autonomous Institutes (November, 2014):

These are the latest rules. They apply only to the State Goverment’s Autonomous Institutes—not to the engineering colleges affiliated to SPPU.

But bear in mind that in the view of the State Government (and most every one else), these Autonomous Institutes are supposed to be in the leadership positions; they are supposed to be guide-lamps to the other colleges. It is in this context that their rules become relevant.

I found the document at COEP’s Web site, this year, here [^]. Once again, I have uploaded a copy at my Google Drive, here [^].

See page 3, Paragraph Serial Number 3.2. It says:

“PROFESSOR: Essential: (i)  Ph.D.  Degree  or  equivalent  in  the  concerned  discipline  from  a reputed  institution, preceded  by a UG/PG  Degree in the  relevant  discipline in First Class (or equivalent) with consistently good academic record; ” etc.

Much better (though not as good as the University of Mumbai’s).

Note that the PhD ought to come in the concerned discipline, whereas either the UG or the PG degree should have come from a relevant discipline.

This document thus settles the issue that the Interpretations 1.1 and 2.1 are NOT valid; only the Interpretations 1.2 and 2.2 can be. However, unlike the broadest interpretation in 2.2, here, the requirements are a bit restrictive: your PhD must be in the concerned discipline.

Thus, for the position of Professor in Mechanical Engineering, the following combination is allowed:

BE (Met) + M Tech (Met) + PhD (Mech).

On the other hand, as far as I can make it out (and I can be wrong here), both of the following come in doubt:

BE (Mech) + M Tech (Mech) + PhD (Aero)
BE (Mech) + M Tech (Mech) + PhD (Met)

Looks like they should hire people with better drafting abilities at both COEP as well as in the DTE—and most certainly, and first and foremost, at the AICTE. (Yeah, right. Keep hoping. (AICTE sits in New Delhi.))

I assert that the University of Mumbai’s draft is the best (among those considered above). If you differ, drop me a line.

For obvious reasons, for this post, there won’t be the usual section on a song I like.

I may come back and edit this post, but only for correcting typos/links, or to streamline the write-up.

Since the issues are both legal and important, I may also come back to edit this post any time in a distant future. If so, I will note those (more serious) updates explicitly. (In contrast, the immediate updates merely for streamlining and all, will not be noted explicitly.)

Update 1 on 2016.06.21: Added the detailed rules for Assistant and Associate Professor’s positions at the University of Mumbai. [The link to original document was given even earlier, but now the text of the main post also quotes the detailed requirements.]

[E&OE]

/

# Papers must fall out…

Over the past couple of weeks or so, I’ve been going over SPH (smoothed particle hydrodynamics).

I once again went through the beginning references noted in my earlier post, here [^]. However, instead of rewriting my notes (which I lost in the last HDD crash), this time round, I went straight to programming. … In this post, let me recap recall what all I did.

First, I went through the great post “Why my fluids don’t flow” [^] by Tom Madams. … His blog has the title: “I am doing it wrong,” with the sub-text: “most of the time.” [Me too, Tom, me too!] This post gave a listing of what looked like a fully working C++ code. Seeing this code listing (even if the videos are no longer accessible), I had to try it.

So, I installed the Eclipse CDT. [Remember my HDD crash?—the OS on the new HDD had no IDEs/C++ compilers installed till now; I had thus far installed only Python and PyCharm]. I also installed MinGW, freeglut, Java JRE, but not all of them in the correct order. [Remember, I too do it wrong, most of the time.] I then created a “Hello World” project, and copy-pasted Tom’s code.

Tom’s program not only compiled well, but it also worked beautifully. Quite naturally, I had to change something about it.

So I removed his call to glDrawArrays(), and replaced the related code with the even older glBegin(GL_POINTS), glVertex2d(), glEnd() sort of a code. As I had anticipated,  there indeed was no noticeable performance difference. If the fluid in the original code required something like a minute (of computer’s physical time) to settle down to a certain quiescent state, then so did the one with the oldest-style usage of OpenGL. The FPS in the two cases were identical in almost all of the release runs, and they differed by less than 5–7% for the debug runs as well, when the trials were conducted on absolutely fresh cold-starts (i.e. with no ready-to-access memory pages in either physical or virtual memory).

Happy with my change, I then came to study Tom’s SPH code proper. I didn’t like the emitters. True to my core engineering background, what I wanted to simulate was the dam break. That means, all the 3000 particles would be present in the system right from the word go, thereby also having a slower performance throughout, including in the beginning. But Tom’s code was too tied up with the emitters. True to my software engineering background, rather than search and remove the emitters-related portion and thus waste my time fixing the resulting compiler errors, I felt like writing my own code. [Which true programmer doesn’t?]

So I did that, writing only stubs for the functions involving the calculations of the kernels and the accelerations. … I, however, did implement the grid-based nearest-neighbor search. Due to laziness, I simply reused the STL lists, rather than implementing the more basic (and perhaps slightly more efficient) “p->next” idiom.

Then I once again came back to Tom’s code, and began looking more carefully at his SPH-specific computations.

What I now didn’t like was the variables defined for the near-density and the near-pressure. These quantities didn’t fit very well into my preconceived notions of how a decent SPH code ought to look like.

So, I decided to deprove [which word is defined as an antonym of “improve”] this part, by taking this 2010 code from its 2007 (Becker et al.) theoretical basis, to a 2003 basis (Muller et al., Eurographics).

Further following my preconceived notions, I also decided to keep the values of the physical constants (density, gas stiffness, viscosity, surface tension) the same as those for the actual water.

The code, of course, wouldn’t work. The fluid would explode as if it were a gas, not water.

I then turned my learner’s attention to David Bindel’s code (see the “Resources” section at the bottom of his page here [^]).

Visiting Bindel’s pages once again, this time round, I noticed that he had apparently written this code only as a background material for a (mere) course-assignment! It was not even an MS thesis! And here I was, still struggling with SPH, even after having spent something like two weeks of full-time effort on it! [The difference was caused by the use of the realistic physical constants, of course. But I didn’t want to simply copy-paste Tom’s or Bindel’s parameter values; I wanted to understand where they came from—what kind of physical and computational contexts made those specific values give reasonable results.]

I of course liked some of the aspects of Bindel’s code better—e.g. kernels—and so, I happily changed my code here and there to incorporate them.

But I didn’t want to follow Bindel’s normalize_mass routine. Two reasons: (i) Once again according to my preconceived notions, I wanted to first set aside a sub-region of the overall domain for the fluid; then decide with how many particles to populate it, and what lattice arrangement to follow (square? body centered-cubic? hexagonal close-packed?); based on that, calculate each particle’s radius; then compute the volume of each particle; and only then set its mass using the gross physical density of the material from which it is composed (using the volume the particle would occupy if it were to be isolated from all others, as an intermediate step). The mass of a particle, thus computed (and not assumed) would remain fixed for all the time-steps in the program. (ii) I eventually wanted a multi-phase dam-break, and so wasn’t going to assume a global constant for the mass. Naturally, my code wouldn’t be able to blindly follow Bindel on all counts.

I also didn’t like the version of the leapfrog he has implemented. His version requires you to maintain additional quantities of the velocities at the half time-steps (I didn’t mind that), and also to implement a separate leapfrog_start() function (which I did mind—an additional sequence of very similar-looking function calls becomes tricky to modify and maintain). So, I implemented the other version of the leapfrog, viz., the “velocity Verlet.” It has exactly the same computational properties (of being symplectic and time-reversible), the same error/convergence properties (it too is second-order accurate), but it comes with the advantage that the quantities are defined only at the integer time-steps—no half-time business, and no tricky initialization sequence to be maintained.

My code, of course, still  didn’t work. The fluid would still explode. The reason, still, was: the parameter values. But the rest of the code now was satisfactory. How do I know this last part? Simple. Because, I commented out the calls to all the functions involving all other accelerations, and retained only the acceleration due to gravity. I could then see the balls experiencing the correct free-fall under gravity, with the correct bouncing-back from the floor of the domain. Both the time for the ball to hit the floor as well as the height reached after bouncing were in line with what physics predicts. Thus I knew that my time integration routines would be bug-free. Using some debug tracings, I also checked that the nearest-neighbour routines were working correctly.

I then wrote a couple of Python scripts to understand the different kernels better; I even plotted them using MatPlotLib. I felt better. A program I wrote was finally producing some output that I could in principle show someone else (rather than having just randomly exploding fluid particles). Even if it was doing only kernel calculations and not the actual SPH simulation. I had to feel [slightly] better, and I did.

At this stage, I stopped writing programs. I began thinking. [Yes, I do that, too.]

To cut a long story short, I ended up formulating two main research ideas concerning SPH. Both these ideas are unlike my usual ones.

Usually, when I formulate some new research idea, it is way too conceptual—at least as compared to the typical research reported in the engineering journals. Typically, at that stage (of my formulation of a new research idea), I am totally unable to see even an outline of what kind of a sequence of journal papers could possibly follow from it.

For instance, in the case of my diffusion equation-related result, it took me years before an outline for a good conference paper—almost like really speaking, at par with a journal paper—could at all evolve. I did have the essential argument ready. But I didn’t know what all context—the specifically mathematical context—would be expected in a paper based on that idea. I (and all the mathematicians I contacted) also had no idea as to how (or where) to go hunting for that context. And I certainly didn’t have any concrete idea as to how I would pull it all together to build a concrete and sufficiently rigorous argument. I knew nothing of that; I only knew that the instantaneous action-at-a-distance (IAD) was now dead; summarily dead. Similarly, in case of QM, I do have some new ideas, but I am still light-years away from deciding on a specific sequence of what kind of papers could be written about it, let alone have a good, detailed idea for the outline of the next journal paper to write on the topic.

However, in this case—this research on SPH—my ideas happen to be more like what [other] people typically use when they write papers for [even very high impact] journals those which lie behind the routine journal papers. So, papers should follow easily, once I work on these ideas.

Indeed, papers must follow those ideas. …There is another reason to it, too.

… Recently, I’ve come to develop an appreciation, a very deep kind of an appreciation, of the idea of having one’s own Google Scholar page, complete with a [fairly] recent photo, a verified email account at an educational institution (preferably with a .edu, or a .ac.in (.in for India) domain, rather than a .org or a .com domain), and a listing of one’s own h-index. [Yes, my own Google Scholar page, even if the h-Index be zero, initially. [Time heals all wounds.] I have come to develop that—an appreciation of this idea of having a Google Scholar page. … One could provide a link to it from one’s personal Web site, one could even cite the page in one’s CV, it could impress UGC/NBA/funding folks…. There are many uses to having a Google Scholar page.

…That is another reason why [journal] papers must come out, at least now.

And I expect that the couple of ideas regarding SPH should lead to at least a couple of journal papers.

Since these ideas are more like the usual/routine research, it would be possible to even plan for their development execution. Accordingly, let me say (as of today) that I should be able to finish both these papers within the next 4–5 months. [That would be the time-frame even if I have no student assistant. [Having a student assistant—even a very brilliant student studying at an IIT, say at IIT Bombay—would still not shorten the time to submission, neither would it reduce my own work-load any more than by about 10–20% or so. That’s the reason I am not planning on a student assistant on these ideas.]

But, yes, with all this activity in the recent past, and with all the planned activity, it is inevitable that papers would fall out. Papers must, in fact, fall out. …. Journal papers! [Remember Google Scholar?]

Of course, when it comes to execution, it’s a different story that even before I begin any serious work on them, I still have to first complete writing my CFD notes, and also have to write a few FDM, FVM and VoF/LevelSet programs scripts or OpenFOAM cases. Whatever I had written in the past, most of it was lost in my last HDD crash. I thus have a lot of territory to recover first.

Of course, rewriting notes/codes is fast. I could so rapidly progress on SPH this year—a full working C++ code in barely 2–3 weeks flat—only because I had implemented some MD (molecular dynamics) code in 2014, no matter how simple MD it was. The algorithms for collision detection and reflections at boundaries remain the same for all particles approaches: MD with hard disks, MD with LJ potential, and SPH. Even if I don’t have the previously written code, the algorithms are no longer completely new to me. As I begin to write code, the detailed considerations and all come back very easily, making the progress very swift, as far as programming is concerned.

When it comes to notes, I somehow find that writing them down once again takes almost the same length of time—just because you had taken out your notes earlier, it doesn’t make writing them down afresh takes any less time.

Thus, overall, recovering the lost territory would still take quite some effort and time.

My blogging would therefore continue to remain sparse even in the near future; expect at the most one more post this month (May 2016).

The work on the journal papers itself should begin in the late-June/early-July, and it should end by mid-December. It could. Nay, it must. … Yes, it must!

Papers must come out of all these activities, else it’s no research at all—it’s nothing. It’s a zero, a naught, a nothing, if there are no papers to show that you did research.

Papers must fall out! … Journal papers!!

A Song I Like:

(Western, Instrumental) “The rain must fall”
Composer: Yanni

[May be one quick editing pass later today, and I will be done with this post. Done on 12th May 2016.]

[E&OE]