Physicists Don Page and William Wootters have come up with an experiment to explore the time problem in that developed from the Wheeler-DeWitt equation that attempts to merge quantum mechanics with general relativity. This equation had a problem that the universe it described was static as seen from outside the universe. Page and Wooters show that time emerges from entanglement because it allows beings inside the universe to measure events by measuring changes in entangled states. In the paper,
Quantum Experiment Shows How Time ‘Emerges’ from Entanglement, the polarization states of two entangled photons are measured relative to each other in one case, and then measured referenced to an external clock in the second case. The relative measurements show changes in the system where as the measurements made using the external clock do not show any changes. The full paper can be found no the
arXiv server.