A bright star has gone dark.
Astrophysicist Jayant Narlikar died in Pune on May 20. He was 87.
He devoted his life to the quest for scientific knowledge, the advancement and dissemination of rational thought and the steadfast struggle against pseudoscience.
There is perhaps no student of science in India today who must not have heard of Narlikar. Using chalks of various colours and a blackboard, Narlikar imparted lessons on the universe, and our place in it, to generations of students.
Narlikar was born in Kolhapur in 1983. His father was a professor of mathematics at Banaras Hindu University. Narlikar followed in father’s footsteps, graduating in mathematics from Banaras Hindu University and then pursuing higher studies at Cambridge, where he was awarded the Tyson Medal in the Mathematical Tripos course. At Cambridge, Narlikar met renowned British physicist Fred Hoyle.
In the 1960s, radio astronomer Martin Ryle provided new experimental data to Cambridge University’s Cavendish Laboratory, supporting the Big Bang Theory. The universe began as an infinitely small, hot, and dense point that swiftly expanded and proceeded to stretch for 13.8 billion years, according to the Big Bang Theory.
Narlikar and Hoyle used Ryle’s data to show that his results were inconclusive for the Big Bang Theory. Their research yielded the Hoyle-Narlikar theory, also known as the Quasi Steady State Cosmology Theory or Conformal Gravity Theory. It presents an alternate explanation for the formation of the universe. Unlike the Big Bang Theory, the Steady State Theory contends that the cosmos is constantly expanding and creating new matter.
This theory asserts that the mass of every object in the universe is affected by its interactions with other objects. Physicist Albert Einstein was inspired by this principle, but could not incorporate it into his theory of relativity.
Narlikar and Hoyle’s theory proposed a “creation field”, which is a hypothetical negative energy field that continuously creates matter, explaining the Steady State Universe: the universe has no beginning or end, it goes on forever. Their theory gave rise to an alternative understanding of the structure of galaxies, the distribution of matter and cosmic microwave background radiation.
In his autobiography, My Tale of Four Cities, Narlikar uses a banking analogy to describe how the world expands steadily while retaining a constant density:
“To understand this concept better, think of capital invested in a bank which offers a fixed rate of compound interest. That is, the interest accrued is constantly added to the capital which therefore grows too, along with the interest. The universe expands like the capital with compound interest. However, as the name ‘steady state’ implies, the universe always presents the same appearance to any observer. Such an observer, for example, can measure the density of the universe from time to time. He or she should find the universe to have the same density at all times. How is this possible, when we know that anything that expands becomes diluted and less and less dense?”
To answer this question, wrote Narlikar, cosmologists Hermann Bondi, Thomas Gold, and Fred Hoyle “had to conclude that there is new matter created to make up for the diminishing density of existing matter”.
This theory makes it possible to explain how stars dating back billions of years can be found, but it is not possible in the Big Bang theory, because it posits that the universe is 13.8 billion years old. The Steady State Teory, based on mathematical principles, is not universally accepted but gave rise to new debates in cosmological research.
Narlikar’s research on black holes was just as highly regarded. He proposed the concept of a self-gravitating system, which examines the gravitational impact of matter on the geometry of space-time surrounding black holes. A self-gravitating system is one in which the gravitational forces between its components are strong enough to keep the system together and prevent it from dispersing.
His studies also focused on active galactic nuclei – AGN. These are the extraordinarily bright, compact centre regions of galaxies where a supermassive black hole actively accretes matter. Narlikar’s research centered on the dynamics of black holes and the behaviour of energetic galactic sources, which included the creation of his “magnetic field ejection model”. It is a cosmological model that proposes that magnetic fields cause quasars and other intense objects to be expelled from galaxies, explaining their observed redshift, which is when galaxies appear to emit red light, and other features.
Upon returning to India from Cambridge in 1972, Narlikar joined the theoretical astrophysics group at the Tata Institute of Fundamental Research, where he remained for 17 years. Under Narlikar’s guidance, the institute’s Department of Theoretical Astrophysics achieved global acclaim in the mid-1980s.
In 1988, the University Grants Commission entrusted Narlikar with the establishment of the Inter-University Centre for Astronomy and Astrophysics in Pune. The centre, founded by distinguished scientists such as Ajit Kamdevi and Naresh Dadhichi, is now recognised as a premier institution in astronomy and astrophysics, both in India and internationally. Under Narlikar, the centre cultivated a multitude of emerging scientists. He retired as the centre’s director in 2003.
Narlikar was also a dedicated advocate for science. He was prominent in Maharashtra’s anti-superstition movement. With scholars and activists Sudhakar Kunte, Narendra Dabholkar, and Prakash Ghadpade, Narlikar demonstrated the ineffectiveness of astrological predictions.
In 2018, he attended a science conference organized by the Breakthrough Science Society at Jadavpur University. Only months before his death, in February he had participated in the All India Science Congress in Trivandrum, Kerala.
He exemplified the scientist who was an equally effective public speaker.
Narlikar was also a science fiction writer, especially for younger readers. He wrote in Hindi, English and Marathi. Many students of the 1990s grew up reading Narlikar’s writing, especially his novels.
Decades before Covid-19 and artificial intelligence, Narlikar, in The Plague of Athens, wrote about the pandemic that followed a virus brought to earth by an asteroid. In another story, Narlikar wrote about super-intelligent robots, somewhat like ChatGPT today. Throughout his life, he also wrote articles to help ordinary readers understand complex scientific subjects.
His achievements were celebrated early in his life, with Padma Bhushan at the remarkably young age of 27. Narlikar went on to receive several awards: the Adam’s Award (1967), Kalinga Award (1996), Padma Vibhushan (2004), and Maharashtra Bhushan (2011).
In the July 1964 issue of the National Planning Commission’s magazine Yojana, a column asked “Should we get Jayant back?” He was 26 years old then. Today, that line is just as relevant.
Shamim Haque Mondal is a researcher in the Physics Division, State Forensic Science Laboratory, Kolkata.
