Homi Bhabha exchange programme

Chris White meets an eminent physicist visiting from India.

Tour gives a global view

Dr Bikash Sinha

“I’ve totally enjoyed myself so far, because I was an undergraduate in Cambridge and did my postgraduate fellowship here at King’s in London, so I’m back in contact with lots of friends after many years,” says Bikash Sinha, director of the Saha Institute of Nuclear Physics and the Variable Energy Cyclotron Centre, both situated in Calcutta, India.

Sinha, 63, was in the UK having been chosen to give the Homi Bhabha Lectures by the Indian Physics Association, of which he is president. These consist of a series of talks given at institutions across the UK, and are named after the physicist considered to be the father of India’s nuclear programme. An Indian physicist has presented them in the UK in even-numbered years since 1998, alternating with the Cockroft-Walton Lectures, given by a UK physicist in India.

“My first stop was Cambridge, where I did a lecture on environmental issues: climate change and sustainable energy. The demand for energy is increasing rapidly and that’s creating problems in terms of pollution and climate. How do we balance things?

“The other lecture was on the ‘mini bang’ and the Big Bang – the mini bang meaning nuclear physics and
the large hadron collider in Geneva, where experiments recreating the microseconds immediately after the
Big Bang are taking place. So in certain places I’ve been doing the cosmological talk and in some places I’ve been doing the energy talk. It depends on the tastes of the audience.”

The former topic relates directly to Sinha’s work as a nuclear physicist, since the issue of climate change is encouraging a shift away from fossil fuels to solar and nuclear energy. “The energy problem is such a serious issue for scientists to be involved in,” he says. “I’m trying to advise our government, to assess things and to make people aware of the problem.”

Growing up in Calcutta, Sinha’s family often received visits from eminent Indian musicians, artists and scientists such as S N Bose, after whom Bose–Einstein statistics and the Bose–Einstein condensate are named. At the time, the city was the centre of industry and science in India.

“Calcutta when I was young was very different from Calcutta now,” he says. “When I was growing up there during the 1960s it was the commercial capital of India. Everything was happening there; the airport was busy. Over the years, for a number of reasons, all of the industrial and commercial activity moved to Mumbai. Although even now Calcutta and science have a very strong connection.”

After graduating from the University of Calcutta with a first-class honours degree in physics in 1964, Sinha
went to Cambridge and obtained a BA in natural sciences in 1967 followed by an MA in 1968.

“The college I went to in Calcutta is quite famous, to the extent that when I came to Cambridge I found some of the lectures, even by eminent people, were already known to us,” he says. He recalls the late Sir Brian Pippard teaching from his own textbook, from which Sinha had been taught in Calcutta. “When I started attending his lectures and then [subsequently] didn’t go, he asked stridently ‘Why don’t you attend my lectures?’ I said: ‘I know exactly what you’re going to talk about.’ He understood what I meant, as he knew that there was a guy who taught from his book in Calcutta.”

Although Sinha was then Cambridge’s only Indian student of natural sciences, it had previously been home to some eminent Indian scientists from the 19th century. Sinha was back in Cambridge in December for the unveiling of a bust of Jagadish Chandra Bose, who pioneered radio science.

After Cambridge, Sinha took up postgraduate study jointly at King’s College London and the Rutherford High-Energy Laboratory, submitting his PhD thesis in 1970. He stayed on as a research fellow, conducting research on optical potential and nuclear structure until 1976, when he returned to India at the invitation of Raja Ramanna, who was then director of the Bhabha Atomic Research Centre, at their nuclear physics division in Mumbai. Sinha had come to his attention after he had papers published on what happens when two atomic nuclei come close to one another (in 1973) and on a method to help determine the behaviour of nuclei during radioactive decay (in 1975).

He moved to the Variable Energy Cyclotron Centre in Calcutta in 1985, becoming director in 1987. In addition he became the director of the Saha Institute of Nuclear Physics in 1992. Despite running two organisations, Sinha has still found time to conduct his own research. “First I did low-energy nuclear physics. Over the last two years I’ve been doing high-energy nuclear physics, looking for signals of a new state of matter that we expect to form, called quark–gluon plasma,” he says. The signals predicted by Sinha were used to look for quark–gluon plasma in particle accelerators such as the relativistic heavy ion collider at Brookhaven National Laboratory, where its discovery was provisionally announced in 2005.

“I’m very fortunate to have my own group and to have a lot of young people working with me,” says Sinha. “Some of them have been with me since they were students and are now distinguished colleagues.”