String Theory and the Conundrums of Quantum Gravity

We give a brief survey of the attempts to understand the quantum dynamics of general relativity through the lens of quantum field theory, which has been successfully applied to the other fundamental interactions. This approach began by naively quantizing spin two massless particles but quickly ran into difficulties when considering quantum corrections to the interacting theory. We will describe how the early incarnations of string theory successfully addressed these problems. Then we go on to sketch how one has been able to go beyond this 'perturbative' picture by giving a tight microscopic description of black hole thermodynamics. This in turn has led to the much more subtle holographic description of the quantum dynamics of a large class of spacetimes which has been one of the primary engines of theoretical developments in the last couple of decades.