Interview/Prof. Ashok Sen, one of the world's leading physicists
The first thing that strikes you when you meet Ashok Sen, one of the world’s leading theoretical physicists, is his thick lensed spectacles. They are so thick that his cautious, intense eyes look enlarged behind it. (The power is –12 in one eye and –13 in the other: he suffers from myopia, with a touch of astigmatism, Sen says later.) He is dressed casually in a blue T-shirt and trousers and leather slippers and is in an animated discussion with a group of students of the Tata Institute of Fundamental Research. The discussion, though held in English, went, by a conservative estimate, a few kilometres over my head. I kept hearing the word, ‘coupling’, which, in normal life, should have been exciting but in theoretical physics, it could be as exciting as a bikini-clad Pamela Anderson standing in front of a gay man. Suddenly, a face popped in at the door and asked Sen where he would like to go for dinner. “Anywhere is fine,” he replied. “For me, food is just food.”
Excerpts from the interview:
In simple terms, could you explain the string theory?
String theory is based on the idea that even though the quartz and electrons and other elementary particles look as if they are the fundamental units, each of these particles, by themselves, are going through some specific vibrational state, like a string. According to the theory, there is a single type of string and this can vibrate in various modes, which appear to us as different elementary particles. One of the advantages of this theory is that one of the modes of vibration of the string turns out to have the property of a particle that can radiate a gravitational interaction.
What are the benefits for mankind?
I would think mankind would like to know how the universe functions. Whether it will have any practical benefit or not, we cannot say at this moment.
How many years have you been doing research on string theory?
Since 1985. How did you get interested in this theory? I started working on it at the end of my post doctoral fellowship at Fermi National Accelerator Laboratory in USA and that was the time when some of the new results in string theory had come up; and I got excited by that. I thought string theory seemed to be the most promising way to understand the universe.
Can you tell us something about your background?
I did my schooling and graduation from Calcutta, my masters in the Indian Institute of Technology, Kanpur, and my doctorate in particle physics at the State University of New York, Stonybrook. Thereafter, I went to Fermi Lab for a post doctoral fellowship, and from there I went to the Stanford Linear Accelerator Centre for my next post doctoral thesis. Then I returned to India, to the Tata Institute of Fundamental Research in Mumbai in 1988. I was there till 1995 and now, for the past ten years, I have been with the Harish Chandra Research Institute in Allahabad.
What made you come back?
I always wanted to come back. Because I was working in theoretical physics, I did not think coming back was a disadvantage. In theoretical physics, the advantage is that you don’t need equipment. That is one of the problems that experimentalists face: their equipment gets stuck in bureaucracy and red tape.
When Indian scientists go abroad they do well. But they seem to lack the environment to shine here. Is this true?
I don’t know about other fields but in the area I work in, theoretical particle physics, scientists in India are doing well. In fact, string theorists in India are at a higher level than Indian string theorists abroad.
Is it true that theoretical physicists do their best work when they are young? Albert Einstein nailed The Theory of Relativity at 36.
That is hard to say. Some people do their best work when they are young, some when they are old. It depends on how you mature as a person.
What are the qualities of a good theoretical researcher?
You need the ability to solve problems. Even if it is not working, you should have the ability to endure the disappointment and carry on. You have to be very patient.Man has made so much of technological advancement. Because of stem cell research, we can do human cloning.
What are the moral implications of this?
All technological development can be used in a good or bad way. Society has to ensure that it is used in a good way. For example, electricity has given us so many benefits but it can also be used to electrocute people.
What is your philosophy?
I don’t have any philosophy. From the scientific point of view, life is just a consequence of the basic laws of nature, just like everything else.
Do you believe in God?
No. The concept of God negates what we are trying to achieve. We are trying to understand how the universe works. And the universe does not work because some power decides that this is how it works.
What happens when we die?
Scientifically, it is just a change in the chemical structure. Some people say they can communicate with the dead and can see ghosts.
Do you think all this is just in the imagination?
Since I have never encountered it, I cannot say it is true. I have to base my judgement on what I know. I cannot believe in another viewpoint, which contradicts what I believe is true scientifically. Everybody has their own way of looking at life. Not everybody wants to look at things scientifically. And I have no problems with that.
Do you have any hobbies?
I read science fiction: Isaac Asimov and Arthur C. Clarke.
I am told that, after Amartya Sen, you are, most likely, to be the next Indian to win the Nobel Prize.
That is completely wrong. I hope you will correct it.
What are your future plans?
I want to understand string theory. Previously, there were five different string theories. Now we know that the five different theories are basically different strands. The problem is when you view something from different sides, you never get the full view. What I am trying to do is to get the overall view, the big picture of the universe.