'Time was speeding up, slowing down, or even stopping': Physicist demonstrates a key theory of time by building a 'mini-universe' in his lab

A physicist at the University of Birmingham built a "mini-universe" using ultracold atoms to test where time comes from — since the universe has nothing outside it to act as a clock. By splitting the system in two and ignoring one half, Giovanni Barontini showed that time can emerge purely from within a system through entropy exchange, speeding up, slowing down, or stopping entirely based on internal activity.