Giovanni Barontini has turned a cloud of ultracold atoms into a miniature Universe, then watched something physicists have argued about for decades seem to happen inside it: time emerging from within the system itself. The experiment, published on June 11 in Physical Review Research, used a Bose-Einstein condensate so isolated that it had no outside clock to lean on.
That is why the study is drawing attention now. It is not just another clever lab setup. It is a direct test of relational time, the idea that time is not handed to a system from outside but arises from relationships inside it. In the language of the Wheeler-DeWitt equation, the universe is treated as a whole system with no external time parameter, and that has been one of the stubborn problems in quantum gravity for nearly 60 years.
Barontini, an experimental physicist at the University of Birmingham in the U.K., built his sample of reality from thousands of atoms cooled to near absolute zero. In that state, they blur together into a single quantum object behaving as one. He then divided the condensate down the middle with a thin sheet of laser light, watched one half closely, and deliberately ignored the other half, which he called the dark sector.
The half he tracked became the bright sector, and its behavior gave him a built-in clock. The atoms sloshed back and forth in the trap and periodically spilled over the barrier and back again, while he tracked how entropy changed in the system. In his language, atoms flooding into the bright sector were the Big Bang, and atoms draining out were the Big Crunch. By following those changes, he could read the flow of time from inside the system rather than impose it from outside.
Barontini said the pieces only made sense when put together, and he described the way time inside the system could speed up, slow down or even stop as surprising. He also said the result came together very neatly, which is not something that happens often in experiments. That matters because the work does not claim time is an illusion or that physics has discovered a cosmic trick. It says something narrower and more powerful: that a system can carry its own time markers when it is isolated enough to have none from the outside.
The result is the first experimental look at why the Universe has time at all, and it gives physicists studying quantum cosmology and thermodynamics something they did not have before: a quantitative lab test of an old idea. Barontini compared the work to what scientists do every day in laboratories, saying they play with very expensive toys and create their own small samples of reality. In this case, the toy is also the point. The next question is not whether the model worked, but how far the same logic can be pushed in other isolated systems before the boundary between a lab sample and a real Universe gets harder to see.
