Narlikar, J. V.2012-03-312012-03-312011-04-10http://hdl.handle.net/11007/1682The underlying idea in Mach's principle is that the origin of inertia or mass of a particle is a dynamical quantity determined by the environment, in particular the rest of the matter in the universe. In this article, we discuss the role of this idea in the Brans {Dicke theory of gravitation and the Hoyle {Narlikar cosmology.enInertiaNewton’s bucket experimentCosmologyArticle