SDM: SDM & Molecular Spectroscopy

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SDM & Molecular Spectroscopy

SDM once showed me his article on Molecular Spectroscopy. I remember to have browsed through it. I saw a Table in it comparing the experimental values of some spectroscopic lines with his calculated values. That was perhaps one of the few papers in which his work had numerical calculations and comparison with experimental results. It was a remarkable work, reducing the solution of the complicated multi-dimensional Schrodinger equation to a one-dimensional Hill’s equation. He narrated to me how Coulson made him jump into his car and gave him a few minutes’ audience, during which Coulson suggested that he be careful about the BKW approximation he was using in the solution of the Hill’s equation. That work was the starting point of his entry into Group Theory.

He then drifted more and more towards pure theory. Even his Cherenkov work was heading for the unverifiable.

With my experimental physics background, I was trying to steer him towards predicting some of the experimental results and photos of Cherenkov rings obtained by Zrelov; but he was hesitant, a streak I could understand, but not appreciate. I wrote to Zrelov in Moscow to send me some photos of his Cherenkov rings in a uniaxial calcite crystal for inclusion in my thesis, with the promise that I would send him a copy of my thesis (costly those days, when no Xerox was available, and an extra copy had to be typed on the mechanical typewriter tap...tap...tap). Zrelov was pleased and sent me five sets of Black and White photos for my five copies of thesis and two big colored photos with rings along and perpendicular to the optic axis. I bought a stainless steel double-photo frame that made quite a hole in my pocket, inserted Zrelov's colored rings in it and gifted it to him. The ring diameter depends on the refractive index and hence dispersion in the optical region; therefore the rings are multicolored, like a rainbow, but elliptical, with a predictable angular distribution of intensity. He kept that photo frame on his refrigerator and used to show it off to one and all. So child-like innocent was he that he carried it wherever he went after retirement. And I was told by DB that the frame with the faded rings was still on his book shelf at Salt Lake just before he died.

In his later years, he himself wouldn’t touch anything to do with experimental results, a weakness which was to cost him dear in getting due recognition. And it was only after he left KGP that his students could extend his work into what IS experimentally verifiable in biaxial crystals (much more complicated but fascinating).

Most of his failings stem from his FIERCE independence (a trait I could guess he owes to India's Freedom Struggle through which that generation passed). .I watched SDM wince when he had to borrow any formula from anyone unless he happened to genuinely admire him. This meant that, while others were building Physics (as Fermi once said) one’s brick over his predecessor’s, SDM was plowing a lonely furrow.

Unfortunately, it works in Arts, but not Sciences. Sad!

SDM: SDM & Teaching

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SDM & Teaching

One of the facets of his 'much-misunderstood' and 'much-maligned' personality is that SDM never cared for teaching, or impressing an audience. His mind was always 'elsewhere'. I am sure while he was ‘taking’ a class he was cracking one of his absorbing research problems. He would drivel, and his audience smirks politely.

Any third grade teacher like me could talk on one of ‘his’ papers and get a big applause. He himself could never do it. But, if I or DB went to his room after his ‘lecture’ and sat down with him, he would go on for two hours about the Naxalite Menace, or Tolstoy or how he saw Dirac go senile at the age of 40 (he went to England to work with Dirac, and met his match in Dirac; both were 'elsewhere' at spatially separated world points). But in between (one has to wait and watch for those golden moments) he would pass such a profound remark or two about the intricacies of his paper, that we could easily churn out half a dozen papers as offshoots, if we wished to.

Once I was struggling to ‘prove’ a hunch I had about one step in our paper which was holding it up. He was to catch a train to Bangalore to talk about 'Unsolved Problems in Physics'. (I am sure the audience there had a tough time following him). I would go to him only when I was about to give up. I went to his Quarters and asked for help. He talked and talked about extraneous things and the rickshaw arrived. Not one to give up easily, I followed him to the railway station, bent on seeing him off. Just before the train left, he made a comment: ‘Doesn't it look like a tensor transformation?’ The train steamed off and as I bicycled back to my bachelor digs, I could see that his comment solved the problem.

By the time he returned after a fortnight, I wrote up the paper. I went to his office to give him my write-up. As usual, he talked on and on for two hours about the fine time he had at Bangalore and what a wonderful city it was and how he would love to settle there after retirement (not speaking a word about how his talk went). He then asked me to give him the unsolved step and he would ‘try’ it. Baffled, I told him that he had already solved it and reminded him of his comment that ‘it looked like a tensor transformation’. He told me that he was not aware of it at all!

There goes the 'genius' at work.

SDM: SDM and his Beam Balance

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SDM & His Beam Balance

My Ph. D. thesis under the guidance of SDM had five papers.

The first two had his name as the first author.

Then on he was too busy with his other works while I was gaining more experience, and was going to him only once in a while to seek some help. When I wrote up the manuscript of our third paper and gave it to him for reading, it had his name as the first author. But, that evening I had one of those last minute inspirations all of us have, and in a ‘night-out’, I finished a long and beautiful calculation. I ran to his Qrs. next morning with my khata. He was having his morning cup of tea in the garden, and thought that I wanted to correct some error in our paper before it was too late. Then, he looked at the end results of my 30 page calculations cursorily, and okayed them in just two minutes (such was his intuition: ‘What looks beautiful is often true’, though not always, as we all know).

I begged him to include these results as the last section of our paper. He fell silent and agreed, but took out the manuscript, and quietly changed the order of the authors so that my name became first. I was glowing with pride to have SDM as the second author. (DB had this privilege often).

By the time I wrote up the fourth paper, he was getting more and more out of calculations in the problem ‘suggested’ by him. When I wrote up the manuscript and submitted it to him, he was silent for a few minutes and said that it should be split up into two papers (Part I and Part II) with his name as the first author in Part I and my name as the first author in Part II. I put my foot down. I reminded him of Solomon’s Judgment; he laughed uproariously. I told him it was going to be just one paper or none. He fell silent again and returned the manuscript deleting his name altogether, with a somewhat heavy heart (like Feynman, he published so few papers that losing one was never easy). He asked me not to forget acknowledging him, with a naughty smile.

The last paper arose from my own ideas. I did the calculation and got the result I intuited, provided I set the value of an integral to zero, without ‘proving’ it. I was hesitant and took my calculations to him and asked him if I was justified to do so. He looked at just that integral, and dismissed my qualms. He said we always set integrals that ‘oscillate at infinity’ to zero, Neumann or no Neumann! My mind was at peace. It was understood that it was going to be my ‘single-author’ paper (how does it matter?). I collected my khata and was leaving. Then he hailed me back. I was worried if something else was wrong. But, no! He simply ordered: ‘Don’t acknowledge me in your paper!’ I could see it was he who was worried (about the rest of my calculations which he didn’t see!).

O, Tempora, O, Mores!

SDM: The Qualifiers

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The Qualifiers

Unlike DB, I joined the Physics faculty at KGP without a Ph. D.

Soon after that, I got sucked into the maelstrom of UG teaching. I was a carefree bachelor then, living in a raucous ‘bachelor faculty hostel’ (Visvesvarayya Niwas), smoking like a chimney, and practically living in the Library, till the night-duty attendants threw me out. Then I would go to my room and read till 2 A.M.

SDM once told me that there was a conviction in Calcutta intellectual circles that no creative work like Theoretical Physics could be done without smoking. Then he would stare at me with a naughty smile, even though I used to give a good 15 minute gap between smoking and entering his room. The wretched stink tells! I can’t stand it nowadays! He told me that he himself graduated from cigarettes to cigars and then on to pipes. I didn’t ask him why he left it, but I know now. Any addiction, as Oliver Wendell Holmes puts it, is less of a ‘sin’ and more of a ‘punishment’. It kills one’s freedom.

So, I had no time, nor inclination to do a Ph.D. This was because many of my senior colleagues used to invite me to work under them, with an ulterior motive, viz. research scholars can run away, but junior faculty can’t. That was why I had to hide in the Library. Neither them nor their problems interested me.

Prof. H.N. Bose was watching me ‘waste’ all my time. He had a soft corner for me (his daughter was in my Electrodynamics class). One day he summoned me and ordered me to go to SDM and join him in his work. I asked him whether SDM does experiments or theory (such was my isolation, although both SDM and me were five years old in the Dept, he as a senior Professor and me as a junior faculty). HNB replied that SDM does wonderful theory, analytical not numerical. That came as a plea for me to escape. I tried to excuse myself saying that my math was weak. HNB thundered that SDM would teach me all the math I needed. I was squirming, but ‘orders were orders’; from a well-wisher HoD.

I then peeped into SDM’s room. And I found a burly man sitting with his feet up and staring at the clean blackboard in front of him, unaware of my entry. After a couple of minutes I gently coughed and he came out of his trance and looked at me. He asked if I was the one who was sent by HNB. I said ‘yes’. He offered me a chair. He then asked me what my ‘achievements’ were. (This seemed to be a routine opening gambit those days). I was blushing and told him I came first in the Andhra University in the MPCE (E for English) group of Pre-University exam. He got curious and asked how many students took that exam. I told him about 2500. He gave a broad (and relieved) smile and mentioned that he himself came first in about a LAKH of students in the Calcatta University Matriculation Exam (Dhaka was included in Cal Univ those pre-partition days). I didn’t know what to say. But there was no need to say it.

He ordered me to get up and go to the blackboard. ‘Draw an ellipse’. That was easy. ‘Draw a straight line intersecting the ellipse’. That too was easy. Then he dictated from his head a complicated function. I wrote it on the board. ‘Collect the residues at the points of intersection’. That stunned me like a whiplash, and I stood staring at the board. He fell silent and went into one of his trances. (He told me much later that his concentration was almost yogic, and he felt he could solve ANY problem that interested him. That reminded me of Somerset Maugham’s description of one of ‘his’ drug-induced trances….he felt so powerful that he could solve ANY problem, but of course felt too lazy to do so!).

Minutes were ticking by and I was dying for a smoke. After quite a while, he took his pen and pulled out a paper from his drawer and scribbled something and pushed it back. He asked me to get my answer and meet him next morning. I took down the ghastly formula and flew like a bat out of hell to the canteen.

That evening I went to the Library and pulled the chit out of my pocket. I did hear of ‘collecting residues’ from my B.Sc. (Hons) days a decade back. We had a wonderful teacher (his name was Dr. Sangameswar Rao ….See, good teachers are remembered even after 50 years) who taught us Complex Variables. So some confidence crept back. I took down Copson and jotted down the residue formula for second order poles. After a night’s work, I got some answer and peeped into SDM’s room the next morning, and handed him my work sheet with a pounding heart. He quickly pulled out the rough sheet in which he scribbled his answer the day before, compared my answer with his, drawing the left index finger on my sheet and the right on his (he was ambidextrous) and declared that I got it right. Profusely sweating, I decided this was the ‘guide’ for me.*

Thus I passed my qualifiers gloriously, thanks to my teacher, Dr. Sangameswar Rao, who I learned had passed away before I could thank him.

Moral: Don’t delay your thanx; ‘here today and gone tomorrow, all flesh is as grass!’

He then pulled out a biscuit-colored reprint from PRS and passed it on to me for reading and asked me to meet him whenever I got stuck. I went to my room, caressing the reprint lovingly. To my great delight I found it was on Electrodynamics with which I had some familiarity; and not Group Theory. The Introduction was so well-written that I fell for his English prose. And then there was an Appendix in which J. L. Synge added an Addendum. Synge was an admirer of SDM, and his book on GR contains SDM’s classic GR work. Synge was my favorite too, because he wrote a wonderful popular booklet titled ‘Kendelman’s Krim’. This was about the ‘infinity’ in pure math. The characters were an Ork, a Kea, a lion and a Carpenter. The Carpenter was just a carpenter, but one of the other animals was a pure mathematician, who asks the Carpenter whether he knows the value of ‘pi’. Carpenter says ‘yes’: it is 3.14; and when he is in a hurry it is 3.

For the next 3 months I used to go to his room every evening, sit down at his feet and get my doubts cleared in working out his PRS paper.

Thereafter my work started ‘running’. I used to solve most of the problems he gave me largely on my own, taking his help only when ‘indispensable’. That suited him. He withdrew from Electrodynamics to concentrate on his Group Theory work with DB.



* I later learned that he was then doing his ‘independent’ paper on ‘Cherenkov Effect in Biaxial Crystals’. He had this thing about him: He should publish at least one ‘single-author’ paper every year, however many collaborators he had. DB knows it. And it was our effort to prise out ‘his’ problems and make them ‘ours’. We never gave up, nor did he. It was a perennial struggle for both.

SDM: Slap or Stimulus?

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Slap or Stimulus?

That was a week or so after I joined SDM. One evening, I went to him with my khata and started showing my progress in cracking his paper (his papers needed some cracking). At one step, I told him, a ‘determinant’ was missing in the denominator. He looked at me quizzically but kept quiet. I persisted. He blew his top and banged me for not knowing that the determinant of an orthogonal matrix is unity. And asked me to go read some ‘Algebra’ book; ‘not Hall & Knight’, but ‘Advanced Algebra’ (to rub salt into the wound). My face fell. I gathered my khata and oozed out of his room. That was the only scolding I got from him, but that was too much to bear. I was shattered.

One weakness of SDM was that he had ‘no roof to his mouth’. The next day, some of my colleagues were sniggering at me in the corridor. I came to know that SDM spread the word that ‘Shastry’s math is katcha’. A lesser soul would have given up going to his room. Well, I am not a lesser soul, and I continued my daily visits. He seemed a little sorry for giving such ‘treatment’ to who, after all, was his colleague. But he said nothing and we had our daily sessions.

Meanwhile I read up all the books on Algebra available in the Library. (Didn’t HNB say that SDM would teach me all the math I needed!)

One year down the line, one day when I was sitting in his room, I found him quietly chuckling. Apparently, he dispatched ‘his’ paper (I think to the Annals of Physics, U.S.A.) that morning. He showed me one step in his manuscript where he was proving a complicated numerator to be exactly zero. He then mentioned that it took 3 DAYS of ‘lengthy calculation’ for him. He challenged anyone, including the referee, to do that calculation in 15 days!

That evening I went to the Library and took down one of the Algebra texts I waded through earlier. After half an hour, I came up with a little known lemma: ‘The cofactor matrix of the cofactor matrix of a 3x3 singular matrix is a null matrix’. (I think I recall well.) That required two steps to prove. Applying it to his ‘numerator’ I got his result in 15 ‘minutes’.

I awaited his entry to his room next morning. He was perplexed, because we met only in the evenings. Then I read aloud the lemma I found, and he started shaking while pulling his manuscript out of his bag. He heaved a sigh of great relief when he saw that he didn’t include his 3 page long ‘proof’ in his manuscript; just out of sheer mischief, playing with the referee (This was one of his other weaknesses. He was always afraid that if he showed his steps, the referee would say that it was all trivial. This turned out to be a good ploy in this paper; but made many of his later papers rather opaque. One shouldn’t play games with referees, when there is no need to do so.)

Then onwards he tried to propagate in equal measure that ‘Shastry has a great insight into math’. That was SDM for you! Very even-handed. Silly, but, of course it didn’t catch on. But, he did remark that I knew that it should be zero, whereas he had only a hunch. Very true! Nonetheless, I did win a handsome Acknowledgment in ‘his’ paper (Not easy, not easy, as Professor G. S. Sanyal would put it, shaking his head in his inimitable style)!

But my troubles had no end. One week after he gave me that sound drubbing, there was this cussed “Doc Screw” meeting. SDM proposed that I should be asked to take; (1) Complex Variables, (2) Partial Differential Equations (both at the M.Sc. level in Math Department), and (3) German (that weakness for Gottingen that was prevalent those days) as my ‘Course Work’.

Anyone else would have felt this was a mean trick on me. The going rule was that Ph.D. students be given M.Tech., not M.Sc. courses as their Course Work. But I thought that was fine with me because I had already taken all of them in my M.Sc. and these were listed in my transcripts.

The teacher of Partial Differential Equations in Math Dept was lenient when I showed him my soiled Sneddon’s tome and my transcripts. I was excused from attending classes and taking the exams.

Then I went to the German teacher, a soft spoken bhadralog who I discovered later on was as tough as nuts and bolts. I showed him my M.Sc. Degree Certificate where it was written ‘German’ against the compulsory foreign language. He smiled and mentioned softly that that degree was a decade old (as if the German language had undergone a metamorphosis in that decade), and asked me to attend all the classes and take all the tests. Phew!

The Complex Variable teacher, a revered old man, was even more uncompromising. I showed him my ‘Complex Variables’ course in my transcripts. But, he said he had his own ‘way’ of teaching that subject and I would immensely benefit from his lectures. He even changed his ‘routine’ kindly to accommodate my off-hours. He didn’t relent. So, I had to sneak into the Math Department and try and sit inconspicuously in the back row, while my ex-students of First Year were sitting in the front row and wondering what gps was doing back out there. That was not all. He used to throw a question and when none of his regular students could answer it, he would ask me to stand up and answer it for the students’ benefit. Everyone would start looking back and it was thoroughly embarrassing for both. And, he insisted that I take the exams with them. And he ‘circulated’ my mid-term answer script as a role model. DAMN!

So goes the Ph.D. I won….’Agony and Ecstasy’.

Moral: There is a very beautiful Telugu poem which I quote verbatim, transliterated into English:

Chaaki kokaludiki cheekaaku padajesi

Maila deesi lessa madichinatulu

Buddhi cheppuvaadu gudditenemayaa

Visvadaabhiraama vinura Vemaa!

This is part of a famous ‘Vemana Shatakam’, translated into English by C. P. Brown in the early 19 th century. I can’t get hold of the English version. Ask any Telugu friend of yours to translate it for you. Briefly, I give just the meaning:

‘The Dhobi thrashes soiled clothes, and hassles them; And then he removes the dirt and presses them into wonderful wear. Just so, what if a Guru, who dispels your ignorance, slaps you once in a while!’

SDM: The Night It Poured

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The Night It Poured

That was a Saturday Evening in August. I knew that SDM religiously took out his wife to the Saturday Evening Show at the Netaji Auditorium, without fail. This was perhaps the only outing the poor lady had in that desolate campus, sans TV, sans phones, sans eateries, sans any sign of civilization. To her, it was a great escape from the routine drudgery. To SDM, it just didn’t matter. Whether it was the sofa in his drawing room or the padded chair in Netaji, it made no difference where he sat. His work needed no pencil, paper or lighting…it was all up there. I read some such remark made by Einstein when he had to stand in a queue somewhere.

Next day was a Sunday, when India were playing Australia. Neither he nor I wanted to miss the ‘commentary’ on our humming pocket transistors. And, I was stuck for three days, unable to determine the limits of an integral that was foxing me in one of our joint efforts. By then I knew what the answer should look like, but I just couldn’t get the limits. Those were my ‘senior’ years with SDM, when he practically withdrew from active calculations, but was helping me when needed.

So, I took out my rusted push-bike and pedaled furiously to his Qrs. to catch him before his rickshaw left for the Netaji. I just made it and showed the thing to him and asked him how to fix the limits. He stared at it for a few minutes, while Mrs. SDM was looking daggers at me (she was a wonderful host and fed me sumptuous loochies in the evenings when SDM wouldn’t let go of me from his reminiscences, but now it was different; the show will start off soon).

He then gave me a hint to draw a parabola; and its intersections with a straight line should give me the limits. The rickshaw chap was hustling and ringing his bells like mad, with Mrs. SDM seated in it. Before boarding the rickshaw, SDM told me that if his suggestion works, I don’t have to report to him; but if it didn’t, I have to go to his Qrs. at 9.30 P.M., when he would be back home from the cinema, so that he could have a second look at it. That was fine with me.

On my way back I saw what an ass I was and how such a simple trick didn’t strike me. His suggestion worked like a charm and the integral was done in half an hour and I proceeded with the rest of the calculation, got very satisfying results as per my hunch; ate my delightful dinner in the tasteless mess and slipped into bed with a Perry Mason trial court scene that I was dying to finish.

And then it started ‘pouring’. You know how it rains in KGP in August, when it decides to. Heavens simply open up. That was smug with me and it was just the weather for a fag or two.

At around 11.30 P.M. there was a knock on my door. I was curious who that could be, in such a foul weather. Opening the door, I found it was SDM himself, with a dripping umbrella and soaked from waist to foot like a wet sock. I asked him to come in, improvised a seat for him somehow, and asked him what the matter was. He asked if his ‘parabola’ worked. I replied that it worked like a wonder. He felt greatly relieved. I told him that I would have gone to his Qrs. at 9.30 P.M. if it didn’t work as per our understanding. He then remarked that he was afraid his suggestion didn’t work, but probably I didn’t feel like going out in such a lousy weather to his Qrs. I was mortified by the misunderstanding and felt that I perhaps should have gone to his Qrs. anyway.

That was SDM!

I gave him a fresh towel, made some black coffee and we two shared some welcome hot drink in wettest weather. I took the opportunity to show him all the progress I made and he was pleased that everything was going swimmingly. We then talked of this and that and I escorted him back to his Qrs; both of us completely wet, but pleased as punch.

Do we have such ‘guides’ nowadays? I wonder!

Talking of drawing parabolas, I am reminded of a story SDM told me (apocryphal, no doubt). It was about a physics student doing his doctorate under a celebrity guide at Oxford. Apparently the two had only two meetings. The first was when the guide gave him a problem. The other was when the student was stuck at one step a year later. He took the problem to his guide, who looked at it and made a pithy remark: ‘Drop a perpendicular’, before hurrying to watch a cricket match. A year later, the student defended his thesis gloriously and, became a celebrity himself.

Epilogue

On the banks of the river Kaveri, the poet-musician-saint Thyagaraja sang that “There are any number of great people in this world”. 

For every great one, there are a hundred greater ones. The really great people know this. And so, they are ever modest.

SDM: Acknowledgments

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Acknowledgments

After my retirement, many of my well-wishers kept in touch with me, and this wonderful gesture on their part helped me overcome my retirement blues.

They also encouraged me to write this article on SDM, read drafts of these files, gave me feed back, and suggested improvements. All of them are either my ex-students or younger colleagues and friends. I thank all of them for their support. Here are their names in dictionary order:

Aniket Basu, Anushree Roy, Arundhuti Ganguly, Indrajit Mitra, Jogia Bandyopadhyay, Krishna Kumar, Pratik Khastgir, Samit Ray, Sayan Kar and Shyamal Chakrabarti.

Professor N. P. Rao (IE & M) was my contemporary and close friend at IIT KGP. All these tales were first told to him 35 years ago as and when these events unfolded, and are being retold to you now from long term memory. He saw SDM and perhaps talked to him too. I thank him for encouraging me, going through these files; suggesting important changes and implicitly vouching for their veracity.

Professor Amalendu Mukherjee (ME), Professor Mainak Sengupta (EE) and Dr. L. V. K. Moorthy (M.B.B.S.) read these files and gave their knowledgeable approval, for which I am indebted.

I am grateful to Professor K. L. Chopra for kindly going through these files and suggesting a much improved sub-title.

Thanks are also due to my wife Rukmini for her encouragement and my son Shreenath for help with the computer.