A Dialogue on the Nature of Gravity

Abstract

I describe the conceptual and mathematical basis of an approach which describes gravity as an emergent phenomenon. Combining principle of equivalence and principle of general covariance with known properties of local Rindler horizons, perceived by observers accelerated with respect to local inertial frames, one can prove that the field equations describing gravity in any diffeomorphism invariant theory can be given a thermodynamic re-interpretation. This fact, in turn, leads us to the possibility of deriving the field equations of gravity by maximising a suitably defined entropy functional, without using the metric tensor as a dynamical variable. The approach synthesises concepts from quantum theory, thermodynamics and gravity leading to a fresh perspective on the nature of gravity. The description is presented here in the form of a dialogue, thereby addressing several frequently-asked-questions.