Lessons from Classical Gravity about the Quantum Structure of Spacetime
  I present the theoretical evidence which suggests that gravity is an emergent
phenomenon like gas dynamics or elasticity with the gravitational field
equations having the same status as, say, the equations of fluid
dynamics/elasticity. This paradigm views a wide class of gravitational theories
- including Einstein's theory - as describing the thermodynamic limit of the
statistical mechanics of "atoms of spacetime". The evidence for this paradigm
is hidden in several classical features of the gravitational theories and
depends on just one quantum mechanical input, viz. the existence of
Davies-Unruh temperature of horizons. I discuss several conceptual ingredients
of this approach.
