Physicist with pillow power
New Delhi, Aug. 1: For Kasturie, a 15-year-old Class XI student in Allahabad, “Ashoke uncle” remains the guy who used to play ferocious pillow fights with her, likes to dance to Dandiya tunes and whose fried fish is as tasty as neem-baingun.
For scientific circles, Ashoke Sen is the theoretical physicist who, after living years with a near-certainty that he would never get the Nobel Prize, has bagged a $3-million (Rs 16.6 crore) prize for his research, the amount nearly thrice that of the Nobel.
Sen, 56, a professor at Allahabad’s Harish Chandra Research Institute (HRI), is among nine scientists picked by a Russian billionaire entrepreneur, Yuri Milner, for the inaugural Fundamental Physics Prize, announced yesterday by Milner’s not-for-profit foundation.
Sen has spent two decades refining a mathematical idea called the string theory that seeks to unify two bedrock theories of physics — quantum mechanics and gravity — and to complete an unfinished task initiated by Einstein.
The Milner Foundation said yesterday that Sen’s work has helped show that multiple string theories are all different versions of a single underlying theory.
“This prize is richly deserved, Sen has achieved a level of international fame that the rest of us can only dream of,” said Sunil Mukhi, a fellow string theorist, who is himself a highly-cited physicist at the Tata Institute of Fundamental Research, Mumbai.
But Sen’s superstar status among theoretical physicists contrasts with what some colleagues say is his “incredible simplicity”. He appears most comfortable in a T-shirt, jeans, and slippers, said Mukhi, who has known him since the early 1980s.
Sen’s wife Sumathi Rao, who is also a physicist at HRI, recalls that Sen bought his first suit and needed some assistance to wear his first tie for a ceremony in London in 1998 when he became a Fellow of the Royal Society.
Sen, born in Calcutta, is the elder son of Anil Kumar Sen, a professor of physics at Scottish Church College, and Gouri Sen, a homemaker. His younger brother is also in academics, teaching commerce in a Calcutta college.
He was drawn to physics and graduated from Presidency College before moving to the Indian Institute of Technology, Kanpur, for a master’s degree, a period during which he was drawn to elementary particle physics, a branch of physics that attempts to unravel the underlying rules that give rise to the myriad subatomic particles.
It was while pursuing a PhD in particle physics at the State University of New York, Stony Brook, that Sen met Rao. After four years of sharing meal-plans, going out on long bike rides and mutual attraction, they married in 1983.
Sen plunged into string theory in the mid-1980s, a time when the idea had gained credence as an attempt to explain the subatomic particles as multiple modes of vibrations of a single fundamental string.
Over the years, Sen has received many awards, among them the Shanti Swarup Bhatnagar Prize, India's highest science award, in 1994, and the Infosys Prize in 2009, an award intended to elevate the prestige of scientific research in India.
So when Sen sent his wife an email last week from Munich, Germany, where he was attending a conference on string theory, telling her that he had been selected for an award, she congratulated him, but didn't think much about it.
Then he called her again from Munich on Friday morning. “He asked me: guess how much? The amount left me totally shocked,” Rao recalled today.
A few hours later that morning, a surprised bank manager in Allahabad asked Rao to visit the bank and explain what a $3-million wire transfer into their savings account was all about. The Milner Foundation had already credited the amount.
While Sen may be best known in scientific circles for his work on strings, close friends and some fellow physicists also appreciate his culinary skills. “He’s a great cook and a great eater — he likes to cook chicken and fish, different kinds of gravy, and he likes the Marathi dishes we make,” said Vaishali Kulkarni, the wife of a fellow physicist Dileep Jatkar at HRI.
The Sens and the Jatkars, neighbours, have been eating dinner together every day for the past decade.
That friendship has allowed Kasturie, the Jatkars’ daughter, to develop a close relationship with the Sens. “She particularly likes the neem-baingun dish that Sen sometimes cooks for us,” Kulkarni said.
“We used to play lots of games and had great pillow fights, but now he helps me with my studies,” said Kasturie, who has chosen science at the Plus-Two level and hopes to study environmental science when she enters university.
On the HRI campus, fellow senior physicists have stopped competing with Sen in dancing to Dandiya tunes, an annual ritual during Diwali festivities on campus. “Once he starts, he goes on and on, and the rest of us have to pull back one after another. He has enormous stamina,” said one campus resident.
Sen and Rao spent five years in the US in post-doctoral positions until 1988 when he returned to join the TIFR and she joined the Institute of Physics, Bhubaneswar. Both grabbed academic opportunities at the HRI and moved there in 1995.
TIFR’s Mukhi, who was a fellow PhD student at Stony Brook, says Sen’s arguments in physics appear rock solid and seem to emerge from deep understanding of the subject’s foundations. “He has this knack of putting together existing ideas and information and developing a new idea in a way that makes us wonder: why didn’t I think of that?”
The string theory remains a mathematical concept, a beautiful mathematical concept, as some of its proponents describe it, but untested. “Testing the string theory would require a billion, billion times the energy we can get in particle accelerators today,” said Mukhi. The inability to test string theory also makes some of its top scientists ineligible for the Nobel Prize which requires ideas to be experimentally verified.
But scientists at the European Organisation for Nuclear Research or CERN in Geneva, where the candidate Higgs boson was announced last month, are also looking for signatures of an idea called supersymmetry. “A future hint of supersymmetry would be a boost to the string theory, although not proof for it,” Mukhi said.