Sizing up the universe
IIT-Madras alumnus Liliya Williams calculated the size of an empty swathe in the universe, a billion light years long. Satyen Mohapatra tells more.world Updated: Sep 11, 2007 01:19 IST
Behind the recent discovery of an enormous hole devoid of galaxies and stars in the universe and nearly a billion light years across, are complex calculations by an astrophysicist of Indian origin at the University of Minnesota, USA.
IIT-Madras alumnus and associate professor Liliya Williams was born in Moscow, but her father Leslie Rodrigues, was born in Vasai near Mumbai and worked for Air India. He met her mother Nina at the Moscow State University.
In 1980, the family moved to Bangalore, where Williams attended Sophia’s School for girls, and the Bishop Cotton’s Boys School for junior college. After IIT, she studied astrophysics at Princeton University. “Astronomy chose me,’’ she told HT in an exclusive e-mail interview. “I even read a book on planets when I was 10 years old.’’
At the college and university level, hardly 15 per cent astronomy professors are women. “Women are as interested in astronomy as men,’’ emphasised Williams. “It’s not clear why there are so few women in astronomy. The main reason has probably to do with societal factors.
Young women don’t see many women scientists or professors and feel discouraged from pursuing these careers.”
In August, a University of Minnesota team announced they had found a swathe of the universe where even dark matter did not exist. Williams calculated the size of the hole using radio and microwave data. “My calculations showed that the void was larger than expected,’’ said Wiliams.
"I hope this discovery will lead to a fuller understanding of the largest structures in the universe," she said. “Our discovery indicates that current theories of the universe on a large-scale lack something important."
The findings support the idea that today’s universe is dominated by dark energy (70 per cent), dark matter (25 per cent) and five per cent of stars and planets. Dark matter probably consists of elementary particles, like protons and electrons, only without charge and without any ability to emit or absorb light. Dark matter ‘feels’ only the gravitational force, and no other forces of nature. Dark energy is the most abundant form of energy in the universe, its nature still mysterious. Williams uses the bending of light rays due to the gravity of objects like galaxies, to construct maps of dark matter distribution. She’s studying how dark matter forms galaxies and clusters of galaxies.
“I like to think about things far removed from daily life," she mused. “The universe represents the largest scales our thinking has access to, and the longest time-scales of 13 billion years."