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Leaves from an Unwritten Diary S. Chandrasekhar: Reminiscences and Reflections*

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Leaves from an Unwritten Diary S. Chandrasekhar: Reminiscences and Reflections* GENERALIA Leaves from an unwritten diary S. Chandrasekhar: Reminiscences and reflections* C. V. Vishveshwara Summer of 1963. Boulder, Colorado in *Based on a public lecture arranged by the just watching and listening to USA. Set amongst the lofty Rocky Indian Academy of Sciences on 13 December him.We were five Indian students in Mountains, surrounded by lush green 1999. the summer school. Three had vegetation, with clear blue skies and come all the way from India. Natu- crisp fresh air, Boulder was just the Bust of S. Chandrasekhar rally we wanted to meet the great The public lecture by C. V. Vishvesh- opposite of dreary New York where I Indian physicist. Chandrasekhar wara was organized on the occasion of was studying. A graduate student at the unveiling of a bronze bust of enquired about where we were from Columbia University aspiring to be- Subrahmanyan Chandrasekhar by Mrs. and what we were interested in one come a particle physicist, I was at- Lalitha Chandrasekhar at the premises of by one. When my turn came, I told tending one of the famous annual the Indian Academy of Sciences and at him that I was studying at Columbia summer schools at the University of the Raman Research Institute. The University hopefully to become a Colorado. Lecture notes of that year sculptor was Paul Granlund of particle physicist.‘Particle physics Minneapolis in Minnesota, USA who had would be dedicated to Professor earlier made a similar bust of Srinivasa is not the main focus here,’ George Gamow to commemorate his Ramanujan and which Chandrasekhar Chandrasekhar pointed out, ‘there sixtieth birthday. One of the lecturers had presented to the Academy in 1985. is a summer school going on at the was William Fowler whose topic was Brandeis University devoted entirely ‘Nuclear and Neutrino Processes in to the subject. Why didn’t you go Stars and Supernovae’. Whereas there?’ ‘I am attending this summer Gamow had done pioneering work on school,’ I blurted out, ‘because it is the Big Bang cosmology, Fowler’s so beautiful around here!’ To this sympathies were with the steady state day it is not clear to me why I said universe. The Big Bang scenario is in a that. Truthfulness, stupidity, sheer way akin to that of the Bible in that nervousness or whatever. both have a moment of creation. Fow- Chandrasekhar gave me one with- ler began his lectures with the state- ering look and turned away.Some ment, ‘There are rumours that George twenty years later, I recounted our Gamow wears a halo, while I am a fol- first meeting to Chandra as I had lower of the Anti-Christ. Let me put come to call him by then. He these rumours to rest once and for all’. looked at me steadily and said ‘You And he went on to show a slide of see, people often think I get angry himself being received by the Pope. As easily. I do not get angry’. He gave it transpired, Fowler was destined to me the good old withering look, but share the Nobel prize after twenty did not turn away. He smiled. The years with one of the other lecturers, stern look was probably a reminder namely S. Chandrasekhar. as to how serious he was about We had heard a great deal about seriousness. I ought to have been grey suit. Distant, as though mak- Chandrasekhar. Yet, an aura of mys- serious about either enjoying the ing a brief visit from a world of his tery surrounded him. I had come to own. Eloquent with precise articula- know about the Chandrasekhar limit tion and with the faintest hint of a through Gamow’s books. In his char- charming lisp. Once in a while acteristic way, Gamow had drawn the words came tumbling as though in celebrated mass–radius curve of white competition with thoughts that dwarfs adorned with Indian motifs and rushed in faster. His lectures bore with terms written in Tamil! The im- the formidable title, ‘The higher or- pression Chandrasekhar made, as we der virial equations and their appli- listened to his first lecture, was striking cations to the equilibrium and displaying all the characteristics that stability of rotating configurations’. have been described time and again It was an unfamiliar topic. But the over the years. Handsome, elegantly logical way in which he developed dressed in a dark the concepts and the formalism was impressive. It was a pleasure CURRENT SCIENCE, VOL. 78, NO. 8, 25 APRIL 2000 1025 GENERALIA terest in gravitational collapse and the participants were Brandon Carter and ultimate fate of a massive star. He was Stephen Hawking. Hawking’s wife yet to coin the name ‘Black Hole’ for Jane cooked for them and invited me to this bizarre end product of stellar evo- join them. But, I was too bashful to lution. Wheeler drove down from accept her invitation. Princeton accompanied by three of his Chandra gave lectures on post- graduate students who have over the Newtonian approximation in general years distinguished themselves in rela- relativity. He attended all lectures by tivity – Uri Gerlach, Robert Geroch and the others assiduously. Sometimes Kip Thorne. I vividly remember Lalitha, whom I met for the first time, Limit of mass Chandra sitting at the head of the long appeared to be taking notes. If Rockies or attending the summer seminar table, Misner on his right and Chandra was undecided about the school, not both, which meant neither. Wheeler on his left, and all of us stu- importance of a seminar, he would lis- The smile was the result of a long- dents gathered round trying to catch ten for a few minutes standing at the standing association. Over the years, I every word that was exchanged. And back accompanied constantly by a had come to appreciate his innate were they exchanged! Words, facts, graduate student who was also warmth and friendship buried beneath concepts, ideas ranging over a wide dressed in a formal grey suit. If the his outer shell of reserve. After all, one variety of areas – stars, mass limits, seminar was interesting, Chandra has to get close to the moon to see the collapse, end points and so on. I have would sit down. Otherwise, he would other side. Such a closeness growing often wondered why this event signal to the student by cocking his gradually over a period of more than seemed to be of such overwhelming head like a gangster in a Hollywood three decades becomes part of one’s importance. It was more than a meeting movie and off they would go to do own life. As Lord Tennyson wrote in of giants. It was a symbol of the union their own calculations. his Ulysses, between two disciplines, namely as- In those days Ithaca was a sleepy trophysics on the one hand and gen- little campus town. The downtown I am a part of all that I have met, eral relativity on the other that would area close to the university was not Yet all Experience is an arch eventually open up new vistas in as- the vibrant haunt of the students as it wherethro’ trophysics and cosmology. At the end is today. There was a theatre special- Gleams that untravelled world whose of the day, Lester Edelstein, another izing in horror movies with bizarre ad- margin fades student of Misner, and I presented to vertisements like, ‘Blood, blood, Forever and ever, when I move. Chandra, with some hesitation, the set blood! Frankenstein spills it, Dracula of equations governing the perturba- drinks it’. The only American restau- Experience and passage of time cre- tions of the Schwarzschild black hole rant around was too expensive for us ate a composite image of a place or a which we had recently derived. students. However, there was an inex- person fusing together observation Chandra accepted them with many pensive Chinese restaurant which we and inference. Such a subjective image thanks assuring us that he would be frequented. On one occasion, while of Chandra – all too human side of a interested in them sometime in the fu- some of us were having a boisterous profound scientist – is what I would ture. Little did we realize that eventu- lunch, in walked Chandra and Lalitha like to present. ally perturbations of black holes were as a hush fell over our group. They did The next encounter with Chandra to become a passion with him. For the not see us and took the alcove next to took place at the University of Mary- moment, however, he was just knee ours. A brave member of our group land in College Park. I had moved from deep in the water, preparing himself to even peeped over the divider to get a Columbia University to work with dive to the depths of the ocean. Still a periscopic view of the famous couple. Charles Misner in the general theory of novice, not yet the maestro. We were extremely curious to know relativity. This was a total change of It was as a recent entrant to the field what kind of special vegetarian Chi- interest from particle physics. One day that he appeared at the historic sum- nese food they would order. Perhaps we heard the exciting news that mer school in general relativity that they knew some exotic dishes we were Chandra would be visiting us. We was held in Cornell University, Ithaca, ignorant of. As we strained our ears to knew that he was getting seriously in the year 1965. The names of the par- catch their words, they ordered tossed interested in general relativity.
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