Friday, November 21, 2014

Tables of Integrals - Repeat Telecast

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And then all of a sudden against my initial impulses I swam into the ken of a most unorthodox man of 55 called SDM in 1970. And like our moon I went into a captured rotation for five tumultuous years, facing him all the time and trying to hide my dark side from him. 

For me it was like a change from kabadi to cricket. For SDM it was a novel experience...he told me later that when he went to his alma mater, Cal Univ, on a visit, everyone of his friends asked him if it was true that he was guiding an 'abangalee'. That reveals a lot about SDM and his social skills.

For me again it was a sudden phase transition from the data tables of Landolt-Bornstein to 
the massive tome of Gradshteyn and Ryzhik's Tables of Integrals, Series and Products. The series and products was a fig leaf...it was mostly a table of a thousand integrals, a few of them indefinite and the rest definite integrals of algebraic, circular, hyperbolic and a variety of special functions. I had the book with me for five good years. 

When SDM came to know the Tables I used, he cautioned me not to trust the thing...it bristles with typos as well as bloomers. So I had to go to the original sites they referred to before using them.

SDM himself had the Bateman Manuscripts, Erdelyi's Higher Transcendental Functions and the Table of Integral Transforms of Magnus and Oberhettinger, all of which he assured me were flawless like his favorite Bessel Functions tome of Watson.

I recall an evening when I was asked to go to his Quarters to set forth how to proceed with our next problem of E M Fields of Cherenkov Radiation in crystals. As you know, any EM radiation thing lands you in Fourier transforms. And I sat down in the sofa in front of his and he went into coma for a few minutes and declared:

"It has to come....where can it go? All I have to do is to think for a few minutes. My concentration is yogic, you know"

And he flashed one of his childish smiles and withdrew into his study and emerged with his Magnus & Oberhettinger. And opened it at a page and passed it on to me asking me to apply the Faltung...he never called it Convolution.

And as I opened my khata and took out my pen and got busy, he pushed his right hand inside the front neck of his banian and started kneading his left armpit...a gesture of his 'calculating' mode. This reminded me of Sherlock Holmes's typical gesture when he went into one of his pondering modes:



...He curled himself up in his chair, with his thin knees drawn up to his hawk-like nose, and there he sat with his eyes closed and his black clay pipe thrusting out like the bill of some strange bird. I had come to the conclusion that he had dropped asleep, and indeed was nodding myself, when he suddenly sprang out of his chair with the gesture of a man who has made up his mind and put his pipe down upon the mantelpiece...


When I lifted my head after 5 minutes midway, I saw him smiling naughtily at my labor, much like Holmes used to do to Watson.

And at the end of 15 minutes, I pushed my three-page calculations into his hand and he just looked at the final result and declared it was right. And went into a 2-hour gossip of cabbages and queens...he was allergic to the then professor of chemistry at Cal Univ...his complaint was that she was not good-looking according to him...that was his idea of gender equality...

Not that he never heard of Landolt-Bornstein. A couple of decades back when he was writing up his paper on the spectra of polyatomic molecules which was eulogized by Coulson, he did look into the charts of spectroscopic data. He showed me that paper of his. It indeed had a Table of 'observed' vs 'calculated' wave numbers filling an entire page. As you know, even the spectral lines of hydrogen molecule can't be calculated exactly. I recall reading in Tinkham that chemists had gone as far as a hundred orders of perturbation to get somewhere near the observed results...although there is no rigorous proof of convergence of the perturbation series in general.   


G. H. Hardy apparently summed up the achievements of his life thus:

"I collaborated with Ramanujam on the one hand and Littlewood on the other on more or less equal terms"

And here is the summing up of my academic 'achievements' such as they are:


"I survived the SDM grueling on the one hand and Tarapoda-da's Fourth Year Lab on the other and retired more or less honorably"







...Posted by Ishani

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