Time Emerges from Entropy in a Lab Mini-Universe
A University of Birmingham team built a sealed quantum system of 24,000 ultracold rubidium atoms that mimics a tiny expanding/contracting universe and found that the flow of time can arise from internal entropy changes rather than an external clock. The experiment demonstrates entropic time, provides experimental support for time as a derived property in some quantum gravity theories, and shows the Schrödinger equation can be expressed with entropic time, offering a new laboratory testbed for quantum cosmology and gravity ideas.