Guest Column - Tribute to DB - Supratim Sengupta

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DB (left) & GPS (right)

Farewell to GPS

I vividly recall the first day I met Prof. D. Basu (DB). It was also my first day at IIT KGP and I was unsure at that time whether I would stay or go back to join the M.Sc. programme at Calcutta University. One of my revered teachers at Presidency College (Prof. Shyamal Sengupta) had told me about DB and said that I could go and talk to him. With much trepidation, I entered that famous office (of which GPS was also one of the denizens) that afternoon. For some reason, GPS was not there but DB was and when I told him who I was and that Prof. Shyamal Sengupta had suggested that I meet him, he cordially invited me to sit down and gave me some friendly advice. 

I don't recall everything about that conversation, but one thing I do recall was his statement (using a more evocative Bengali phrase) delivered with typical honesty that he could not speak ill of a place from where he got his salary. But then he went on to give me a balanced view of KGP and gently encouraged me to stay on. I felt reassured by his modesty, simplicity and friendly way of talking to me and that conversation was the tipping point which made me decide to stay on. Both GPS and DB made life in KGP bearable for me.
 

In the next two years, I would enter that office many a time since it always was an oasis of reason, decency and erudition.  During my hunt for an M Sc thesis supervisor, DB was once again kind enough to take me on, much to my chagrin and delight. 

That year I spent trying to wrap my head around the intricacies of SL (2,C) and SL (n,C) representation as enunciated by DB's hero, the great Russian mathematician, I M Gelfand, was quite an experience. Although I as a greenhorn, doubt I could fully grasp the mathematical elegance of that approach, DB's enthusiasm, excitement and deep knowledge of the subject always rubbed off on me and helped illuminate aspects of that beauty which I would never have appreciated by myself.
 

His sincerity and delight came across during his lectures on particle physics as well which I took as a special paper. His lectures were a treat and made me fall in love with quantum field theory. Because of a prolonged illness during my third semester at KGP, I missed a lot of classes, and after I returned he was again kind enough to provide his notes. I ended up transcribing them afresh and I was happy to learn from him the last time we met (in 2005) that he was still using those transcribed notes instead of his older khathas as he used to call them.  
 

After leaving KGP, DB's refusal to use email meant that I would get in touch with him only when I visited KGP occasionally. I met him last in July 2005 when I visited KGP during my trip to India from Canada where I was a postdoc. It was a delight to talk to him again and he even sat through a seminar I gave. I suspect though he was a bit disappointed that I had left theoretical physics and started working on computational biology, but he never said so. We talked for a long time, over chai at the neighbouring Nestle stall, catching up and recollecting memories of my time in KGP.  GPS had left KGP a few months back and DB seemed alienated and isolated from the others in the Dept except Sayan-da and Pratik-da. I also recall that he had just recovered from a serious illness but he seemed fine except for some dietary restrictions. 

Sadly, that would be the last time I would see him.

DB's passion for mathematical physics, his love for teaching, his simplicity and modesty would leave a lasting impression on me. In the present-day scientific community where PR, showmanship and arrogance is often lauded, some people make a far greater and more lasting impact with their understated style, gentleness and passion for science. DB was one such person.

I have been rambling on for too long but writing this has been cathartic in many ways. I will end this with one my my favourite quotes of DB. It was in a Particle Physics class and I don't trust my memory enough to relate the context, so I will just paraphrase the quote. 

DB : "I always tell my children not to lie because lying is always very difficult. When you lie, you create an alternate universe and to get away with the lie, that alternate universe should not conflict in any way with the real universe and that is almost always impossible to achieve."

I always smile when I think of this statement because it is quintessential DB, rational and lucid with an argument so brilliant and devastating in its logic that makes you feel like saying "Bravo" out loud.

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