Physicists created a tiny universe and watched time emerge without a clock

Scientists have created a miniature universe in the laboratory that could help answer one of the biggest mysteries in physics: What is time, and where does it come from? Using 24,000 ultracold atoms, a University of Birmingham researcher built an isolated quantum system that repeatedly expands and contracts, mimicking the Big Bang and a possible Big Crunch. Remarkably, the experiment showed that time could emerge from changes happening inside the system, without relying on an external clock.