Jayant Vishnu Narlikar (born July 19,1938) is an Indian astrophysicist.
Narlikar is a proponent of the steady state cosmology. He developed with Sir Fred Hoyle the conformal gravity theory, commonly known as Hoyle-Narlikar Theory. It synthesizes Albert Einsteins 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.