Emergence of time from quantum gravity

It is generally believed that there is a more fundamental theory than general relativity, which is obtained by employing a quantum description of the gravitational field: a theory of quantum gravity. The fundamental equations of such a theory seem to be of a timeless nature. In my talk, I first review the approach where this issue is most clearly seen: canonical quantum gravity. I then discuss a new concept of time and its consequences at the fundamental level. A major part of my talk is devoted to the demonstration of how the classical concept of time can emerge from quantum gravity in appropriate limits. A central role is played therein by the emergence of classical properties through decoherence. I conclude with some remarks concerning the arrow of time and its derivation from quantum gravity