Jayant Vishnu Narlikar (born July 19, 1938) is an Indian astrophysicist. Narlikar is a proponent of steady state cosmology. He developed with Sir Fred Hoyle the conformal gravity theory, commonly known as Hoyle–Narlikar theory. It synthesizes Albert Einstein’s Theory of Relativity and Mach’s Principle. It proposes that the inertial mass of a particle is a function of the masses of all other particles, multiplied by a coupling constant, which is a function of cosmic epoch. In cosmologies based on this theory, the gravitational constant G decreases strongly with time.
Narlikar was born in Kolhapur. His father, Vishnu Vasudev Narlikar, was a mathematician who served as a professor and later as the Head of the Department of Mathematics at Banaras Hindu University, Varanasi. Jayant’s mother, Sumati Narlikar, was a scholar of Sanskrit language. Jayant studied in Kendriya Vidyalaya Banaras (till class 12) and Banaras Hindu University (12th Onwards) campus, Varanasi.
Narlikar received his Bachelor of Science degree from Banaras Hindu University in 1957. He then began his studies at Fitzwilliam House, Cambridge University in England, where he received a B.A. in mathematics in 1959 and was Senior Wrangler. This appears to have been the first time, and perhaps the only time, that a student was Senior Wrangler who was a non-collegiate member of the University at the time. In 1960, he won the Tyson Medal for astronomy.
During his doctoral studies at Cambridge, he won the Smith’s Prize in 1962. After receiving his Ph.D. in 1963 under the guidance of Fred Hoyle, he served as a Berry Ramsey Fellow at King’s College in Cambridge and earned an M.A. in astronomy and astrophysics in 1964. He continued to work as a Fellow at King’s College until 1972. In 1966, Fred Hoyle established the Institute of Theoretical Astronomy in Cambridge, and Narlikar served as the founder staff member of the institute during 1966-72.
In 1972, Narlikar took up Professorship at the Tata Institute of Fundamental Research (TIFR) in Mumbai, India. At the TIFR, he was in charge of the Theoretical Astrophysics Group. In 1988, the Indian University Grants Commission set up the Inter-University Centre for Astronomy and Astrophysics (IUCAA) in Pune, and Narlikar became the Founder-Director of IUCAA.
Narlikar is internationally known for his work in cosmology, especially in championing models alternative to the popular Big Bang model. During 1994-1997, he was the President of the Cosmology Commission of the International Astronomical Union. His research work has involved Mach’s Principle, quantum cosmology, and action-at-a-distance physics.
During 1999-2003, Narlikar headed an international team in a pioneering experiment designed to sample air for microorganisms in the atmosphere at heights of up to 41 km. Biological studies of the collected samples led to the findings of live cells and bacteria, which introduced the possibility that the earth is being bombarded by microorganisms, some of which might have seeded life itself on earth.
Narlikar was appointed as the Chairperson of The Advisory Group for Textbooks in Science and Mathematics, the textbook development committee responsible for developing textbooks in Science and Mathematics, published by NCERT, which are used widely as standard textbooks in many Indian schools.
The Hoyle–Narlikar theory of gravity is a Machian theory of gravity proposed by Fred Hoyle and Jayant Narlikar that fits into the quasi steady state model of the universe. The gravitational constant G is arbitrary and is determined by the mean density of matter in the universe. The theory was inspired by the Wheeler–Feynman absorber theory for electrodynamics. Currently the theory does not fit into WMAP data. Narlikar and his followers are working on adding mini bangs with various creation fields to explain the anisotropy of the universe.