## Abstract

Drawing on recent developments in the matrix model approach to string theory and the causal set program for quantum gravity we address the question of the origin of time as one aspect of the phase transition from a topological quantum field theory to a quantum theory of gravity. We construct a model with two phases which can be interpreted as containing clocks which either do not tick or tick exactly once. This demonstrates that while a theory based on causal sets may appear to have inherent notions of time and causality, the existence of a phase transition means, that as Saint Augustine wrote in his*Confessions*, “the ‘time’, if such we may call it, when there was no time was not time at all.”

## Keywords

Phase Transition Field Theory Quantum Field Theory Quantum Theory Quantum Gravity## Preview

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